MadModder
Gallery, Projects and General => Project Logs => Topic started by: Bogstandard on January 16, 2011, 08:01:39 AM
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I am taking a bit of time out and building something that has been calling to me for a fair while now. This will run parallel to the Minimag build (when it turns up).
I gave up making things from castings a fair while ago, purely because the quality had got so bad (and still is amongst some of the well known suppliers).
In the middle of last year, I took a chance on a company I had never used before for castings, and bought two casting kits, this one and one for a full sized engine called the R & B, from Bruce engineering.
This one will be used to get me back into the swing of things, because no matter what people say, castings are not an easy way of making things, in fact, if you don't make them right, they can turn out to be an absolute eyesore, or it can cost lots of pennies buying new castings if you bugger up the initial ones. A lot of the second hand part built ones are sold by people who have become disillusioned when they thought they would be getting an easy build.
So now onto the way I get things done, others will have different methods, and as I don't like the way the instructions say how to build it, I will be doing it my way for some of the major parts.
So this is what comes in the kit. Everything you need to make the running engine, ball races, springs, even the fasteners, all except for the burner parts. That is because you have a choice of two methods, spirit and wick or butane/propane mix from a refillable gas tank. I will be going down the gas route, purely because in my steam days, I used to make refillable gas tanks, and I have a fully tested one waiting in the wings.
The quality of the castings, IMHO, are very reasonable, no surface blow holes or sags, intimating that something is amiss inside, and one thing I like the most, they haven't been over fettled by some gorilla using an angle grinder. I can take metal off easily enough, but putting it back on is a PITA.
The plans and instructions are well detailed, and I am sure if you follow them, you would end up with a working engine, which when finished, will be about 10" long by something like 6" wide, so not a small engine at all.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT01.jpg)
When I first bought the castings I had done a little bit of the cleaning up on the flywheel, just a couple of the segments. Now I have new files to fit the die filer, why waste energy.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT02.jpg)
In about ten minutes, I had the whole lot rough fettled, and not one single aching muscle or sore finger, it did a great job. This part will now be put away, and when the time comes to start turning and boring, a smaller and finer file will be fitted and it will be brought down to finished proportions.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT03.jpg)
This is the first piece that will get my major attention, the base casting. BTW, this engine is an Imperial build with BA fasteners, and because that are what are supplied, I will be using them.
So away with the metric measuring instruments, and in with the Imperial. Also, because the base is over 6" long, I will be using an 8" dial vernier rather than the 6" digivern.
The first thing that I did was to roughly check things for square and straightness, they were OK, then check for thicknesses and flatness.
By the time I had given it a good going over, I decided that the four top faces of the base bolt hole bosses were going to be my first datum points.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT04.jpg)
This is the first part that will need cleaning up, the bottom of the base. Once that is done, everything else should fall into place.
I don't like holding directly on the castings because of all the release tapers on them, so the first bit to be made will be a jig plate for it to be bolted to. That will allow me to mount and swing it about to known datums, and so everything will end up nice and square and straight.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT05.jpg)
So get your spurs and chaps on, and enjoy the ride.
Bogs
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Hi Bogs, glad you chose to move on with this one, it looks to be interesting, and I'm looking forward to the part with the burners, as I want to be using gas instead of spirits myself. I very much like bronze for large parts like flywheels and such, so this should be a fine looking engine. :thumbup: mad jack
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Hi Bogs, I will be follow this with a great intresst.
:nrocks:
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All saddled up John! :thumbup:
Head 'em up. Move 'em out...... :D
David D
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If anyone is interested in a little more detail, here is a set of build articles that came from the public domain. I downloaded them and turned it into a PDF to keep it all together.
File name: Scott vacuum engine.pdf File size: 4.52 MB (http://www.fileserve.com/file/geWwz5d)
As you will see. it is not a very difficult an engine to build, all it needs is to keep tolerances under control, as with all flame lickers, and a few specialist bits, like honing the bore and making a gas tank (if you go with gas). The gas tank isn't shown in these articles, but the details are shown fully on the plans, or you can buy a commercial one, plus the feed tube and jet.
Bogs
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Looking forward to this build John!
Eric
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John I'll definitely be watching. As you know I love flame lickers, but I will be picking up bits and pieces for when I eventually make an engine from castings, maybe even a Bruce engineering one.
Nick
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Well a bit more done today, and you will all be saying in the beginning, 'what is that daft old bugger up to now'.
So I may as well explain things a little. Being from an engineering background, you always try to look ahead a little. Well with this post I am certainly doing that. A couple of hours spent making a few fixtures can save many hours over the build of maybe not an engine this small, but anything a bit larger and more complicated, and you will have trouble progressing very far at all without them, so I am taking the opportunity to save myself a little time, and keep things more accurate than I could ever have hoped for if I was just holding the castings in the vice.
First off, I grabbed a bit of my favourite stuff, 12mm thick ali jig plate. Then I machined it square on all sides, and it ended up about 3/4" over the size of the main base casting.
The parallel sticking up the side (there is another one in the opposite direction on the other side) is to help keep things from flopping about and vibrating while being machined, because it is sticking up so far above the vice jaws.
Almost any material can be used for the holding plate, as long as it is sturdy and accurate enough to do the job.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT06.jpg)
A cutout was put into one side, you will see why a little later.
You will also notice the odd hole here and there. When this stuff comes out of a factory as scrap, it has invariably already been used as a jig plate, you just gotta take what you can get.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT07.jpg)
So this is the basic holding plate made, all nice and square and flat.
I suppose you can guess what fits into the cutaway now.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT08.jpg)
So the next job is to find out where to drill the holes in the plate, and this is one of the very few times I will hold a basic casting as large as this in a vice. All because the are usually no straight sides on the casting, so making holding in a vice very unstable. I could have clamped it down to the bed, but that would have meant me removing either my vice or RT, and because I am only doing very light machining on it, I take the chance.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT09.jpg)
I have already decided that the top faces of these bolt hole bosses are going to be my first start datum points, so what I am doing, by eye, is finding the centre of each of the four bosses and spotting it with a ball nosed cutter.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT10.jpg)
This shot shows just how 'bent' the casting is, look at what should be a straight face on the side left hand top edge, and the same on the right hand bottom edge. Now you can see why castings can't be treated like normal bits of metal. They can be bent like a bananas at times, and what you should be trying to do, is not to take all the bends out, but get them looking a little more presentable.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT11.jpg)
So now having the four 'holes' spotted, I can measure up and come to a 'mean' position for the holes. By drilling smaller holes in the holding plate, than the larger ones in the base, it will give a bit of 'fiddle factor later on.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT12.jpg)
The small holes were precision drilled in the plate, and the larger hold down bolt holes were drilled by eye. On the underside of the casting, where it won't be seen, I put recesses for the screws that will be used to hold it down for initial machining.
Also I made four 1" long upstands that were threaded all the way thru. The upstands were first screwed to the holding plate.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT13.jpg)
The plate, tapped down onto parallels, had the four upstands all skimmed on the top faces to ensure they were all the same length
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT14.jpg)
The cast base was then screwed downwards onto the four upstands, the screws went into the recesses while the sticky up bit of the casting went thru the cutout in the holding plate.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT15.jpg)
The whole lot was now gently tapped down onto parallels and everything given a final tighten up.
Then the gnasher came along and took off the hard skin, and the highs and hollows on the base. It took a cut of 0.020" to clean it all up
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT16.jpg)
The fine sweeper then came on the scene, and with a 0.003" cut, took out all the rough machining marks and left behind a nice smooth, perfectly level surface.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT17.jpg)
I now have a main datum base I can actually work with.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT18.jpg)
Everything was cleaned down, the casting taken off and the upstands removed. The casting was then bolted, using all the same drilled holes, onto the holding plate.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT19.jpg)
Once it is mounted back onto the mill, by using a DTI, I can swipe down all the edges and standing up parts, and by gently tapping, I can get the casting into it's optimum position to have any machining done on it.
This will ensure, by using the holding plate as a reference, I will be able to locate all holes and ensure that they are all drilled in the right places and all parallel to each other. Almost an impossible job if you were trying to hold the raw castings by themselves.
This plate will also be reused for the other parts that need machining, so it will not be wasted.
I now hope this goes some way to explaining what the daft old bugger is up to.
John
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Hi John, I just wanted to say, it looks like you're off to a good start. Im looking forward to seeing how this is going to look as it comes together. I've got a casting, a frame for a horizontal steam engine, which has been sitting around for some time for the lack of a good way to hold it to get all the various surfaces machined properly aligned with each other. I think I will emulate you with that piece of tooling plate, and solve a problem I've left for a better day for a few years. Thanks for that idea. I'll be following this one closely. mad jack
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Nice start John
Cant wait for more
Gerhard
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John,
thanks for that. I would never have thought this through logically as you have :smart: but it all makes sense now. I'm glad I've held off trying any casting yet as I would certainly have cocked them up.
I've tried in the past many years ago and never really got anywhere but back then I didn't even really have a feel for limits and fits, let alone geometrical tolerances which is what we are talking about here.
I think by the end of your build I might have picked up some of the knowledge required to have a go at a simple kit of castings but just going to enjoy your article for now.
Nick
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Most times, small casting kits just come with the instructions to file a flat surface somewhere on the casting and work from that. To me that is not acceptable, and why such a lot of beginners fall foul when doing their first casting builds. Usually ending up by throwing it under the bench when everything goes pear shaped.
Unfortunately, castings are all sorts of shapes, purely because the patterns have to release from the mould, and a flat face just won't cut it, so they have shallow tapers everywhere, nothing that you can get a true measurement off.
By me choosing this one major face to get perfect, now very easily, I can, if needed, get a few more faces square to it. Whereas before, I would be stabbing in the dark just where to drill holes and whether they are going to be parallel to each other.
As I said at the start, this build is a sort of prep for when I get onto the real deal, getting me used to working with castings again, because no matter what, if you do go in blind, you will almost certainly end up with some sort of error or bodge on the finished item.
I will say one thing though, working from drawings using bar stock materials is infinitely easier than using castings. It just isn't for everyone.
John
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I can see now that with that careful prep work and making the fixtures it will be a lot easier and you will realise the joy of using the casting. All the basic structure is there requiring a lot less tedious machining hacking metal away. You just need to machine the features in the correct positions, not saying it's going to be easy, but surely less tedious.
Nick
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John,
That was a bit of brilliant work. It's encouraging me to work on that bronze bottle engine again. I should have tought of doing the same since at work they did the same thing with the large machine castings. They were set up in fixtures to get datum surfaces.
One question, maybe more. I noticed you didn't clean off the four bosses were the screws went through. Did you feel confident enough that they were level enough to just bolt down with out warping the whole base plate?
Bernd
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Hi John, while most of my experience in life has been with bar stock, flat stock and making parts for broken machinery and engines, once one has had the pleasure of building out of good quality castings, and come out with a high quality piece of gear, whether an engine or a tool, that does exactly what it's supposed to do, and has the advantages of the casting at the same time, it becomes an agrevation when one has to machine away parts of bar stock which wouldn't exist if it were a casting, and they become the preferred way, if they are well cast with good metal and done by those who really understand patterns, and all the intracacies of taking a drawing and making it into a pattern, casting it, and providing what the machinist needs to work straight forward and not have to make allowances for problems. I just downloaded the pdf file for this engine, and I think you're going to start a run on the casting kits for this engine, with this build. I think it is going to be a work of art and truly beautiful when it is running. The castings look very impressive and well formed, and the design looks very much like something that will attract all sorts of attention, particularly with the big bronze flywheel. :nrocks: mad jack
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Bernd,
I had already measured up the bosses beforehand as best I could, that was the reason for choosing them. Before mounting up, I tried them on the upstands without any screws, and as there was no rocking at all, I left them as they were.
If I had tried to level them with a file beforehand, I could have been playing about for hours trying to get them into a no rock situation.
I took it as a 'leave well enough alone' situation.
As it turned out, when measured from the new datum base to the top of the bosses, they were all within 0.002", so to me, to get a casting that close at this stage of machining is doing rather well. The more small datums that are cut, those measurements will get even closer.
Jack,
I agree with you about production castings, but here in the UK, the quality is so bad with model engine castings, they are almost not worth bothering with, just shapeless lumps of metal full of dross and blow holes and costing an absolute fortune.
That was the reason I took a chance on the two sets I bought, because they looked a definite improvement on what has been available the last time I was making from castings.
Bogs
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Now is the time to start to get the datums on the main bedplate sorted.
You will remember from last time, the bedplate was screwed down to the jig plate, but not yet squared up.
Mounted into the vice, as usual, bedded down onto a couple of parallels and the DTI was then brought into play.
I went all over the castings, looking for areas that matched for squareness, and by taking a few mean figures, I gently persuaded the plate to go into a position where, when machined, datum faces would be produced that would make sure that all the holes will be in the correct position.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT20.jpg)
The front and two side faces were cleaned up, the rear one can be done anytime as that will not be used in any marking up.
Some people will say I am removing too much of the casting features. All I can say is that I prefer to have an engine that is square, accurately made and not having to bodge things to get it running. If needed, the rough finish can be put back on once everything has been machined.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT21.jpg)
With the three sides cleaned up and totally square to everything else, it is time to get some measuring done.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT22.jpg)
The plate was blued up, and by using the two central upstands as datums, I found the centre point between them, and because I had the sides square, by using engineers squares, I could then mark up the centre line and an area of the plate to be machined to become the main vertical datum.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT23.jpg)
You can see here on my sketch and workings out the datum to be produced, and the exact positions vertically to the critical hole positions required.
Now the bedplate can be held accurately, it will be an easy job to get these holes drilled.
Don't worry about the vertical measurements being shown going to the wrong positions, they are in fact the hole centre heights from the datum face.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT24.jpg)
Back onto the mill again, and getting to grips with making the main datum face for the whole engine. What is required is to clean the surface off to remove all hi/lo spots. I found that taking a cut of 0.005" was enough to achieve the goal.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT25.jpg)
Once that flat area was completed, I jumped over to the cast in recess, and because it was full of lumps and bumps, I cleaned the whole lot up to make it look more presentable.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT26.jpg)
This is the finished result, all ready to have the bearing holes drilled and bored in the three uprights.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT27.jpg)
Now we are getting somewhere.
BTW, I was due to be building a magneto in parallel with this engine, and the pre production kit turned up today. But because I also have another little job to do as well, that build will now be delayed until at least next week.
There are only so many hours in the week that I can work.
Bogs
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Bernd,
I had already measured up the bosses beforehand as best I could, that was the reason for choosing them. Before mounting up, I tried them on the upstands without any screws, and as there was no rocking at all, I left them as they were.
If I had tried to level them with a file beforehand, I could have been playing about for hours trying to get them into a no rock situation.
I took it as a 'leave well enough alone' situation.
As it turned out, when measured from the new datum base to the top of the bosses, they were all within 0.002", so to me, to get a casting that close at this stage of machining is doing rather well. The more small datums that are cut, those measurements will get even closer.
Bogs
I had kind of figured that, but was just curious. I know you won't skip an improtant think like that. Talk about luck being on your side.
I'm following this very closely since I'm getting that urge to work on that bottle engine again, but will wait till your done here with this build as I'm re-learning a few things I had forgotten from work.
Keep up the great work.
I'll be quiet now.
Bernd
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Hi Bogs, I got a look at the plans of that engine and it looks like she ought to be a good runner, with very good control over speed and power with gas. In looking at the flywheel of that engine, and that of mine, I think I've got to shed a lot of weight, mine's only a 3/4 inch bore. Is the base plate gun metal as the spec sheet says? I can't tell from the pictures on my computer. It looks like things are going into place nicely, the jig plate idea worked well, and the casting straight. I like castings because they work, save metal, and look good when they're done. In my opinion, they are there for my convenience and savings of metal, machining is for purpose, and straight fitting parts, correct clearances, and reasonable fitment of parts need no excusing, I just hate when things are done to no specific purpose, and no excusing improves the look or finish then. That casting was rather well done for the hopper area to clean up completely with only five thousandths cut. It's good to watch it progress steadily. :beer: cheers, jack
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Bernd,
Maybe it was a bit of luck with those bosses, and the ease at which I managed to get the baseplate level on the bottom, but it is like everything when working with castings, you have to get that initial datum, once that is done, everything else becomes a lot easier.
Some people can just grab hold of a casting and find the datums straight away, unfortunately, I can't do that, so I have to work out everything the hard way. Even though it looks difficult, it isn't really, it is just a matter of sitting down and looking at it logically, the answer is usually staring you in the face.
I don't want to put beginners to casting machining off by what I am doing. It all looks very complicated, but during a conversation with a friend on Skype, I mentioned that even though I have posted a lot already about it, there is only about two hours actual work that has been done. So in fact, it isn't too complicated at all. The act of writing and posting about it makes it look more complicated than it really is.
Jack,
This engine, as far as I know from the plans was dated 1994. It initially called for a gunmetal base, but due to time and of course costs, it now comes with a cast iron base. The water hopper though is still a very heavy gunmetal casting. It's such a shame really, because I have it in my head that I am going to paint it, not polish it, after the initial runs are carried out. I will have to see whether the burner will take the paint off before making my final decision on that.
I wouldn't worry too much about your flywheel being overweight. These engines need as much help as they can get, and having too light a flywheel could stop it running.
Also having looked at the plans on this engine in detail, if you didn't want all the curvy bits to the water hopper (but you could put them on if you wanted to), it could very easily be made from ali and cast iron bar stock, with the uprights being bolted onto a baseplate from underneath. After all, this engine only has three castings, baseplate, water hopper and flywheel, everything else is made up from barstock and commercially available bits.
John
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Off to a flying start John, am watching with interest. Castings seem good quality so far.
Nick
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I too am watching this John. I learn so much from these threads :thumbup:
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I too am enjoying your work. I also really like using the ali plate as a machining base/reference aid, sometimes just figuring out how to hold the object to the mill can be a trial, but this idea is one I will file away.
Tim
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Many thanks gents.
HS93 talked me out of going into the shop this morning, so this is just an easy evenings work.
My DRO had remembered where the centre line was from yesterday, so it was just a matter of getting a zero datum from the end face.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT28.jpg)
Once that was done, it was an easy matter of spotting and drilling the three required holes. Horizontal work on the base is now done, except for drilling the oil cup holes, which can be done at any time, using the datums I have already created, even after it is taken off the holding plate.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT29.jpg)
Now this is where the plate comes into it's own. Swung to a vertical position, and clamped against the vice fixed jaw with a 3,2,1 block. This is plenty rigid enough for the jobs I am now about to do.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT30.jpg)
By having the 3,2,1 block hanging over a little, I can easily find the Y axis setting for the flat face I machined up last time.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT31.jpg)
And the machined end of the casting gave me the X axis position.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT32.jpg)
The X & Y were set to zero
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT33.jpg)
And the figures that I had worked out were fed into the table, the table locks were then tightened up.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT34.jpg)
This put my quill spot on over the position that is shown on the plans. A hole was spotted and drilled.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT35.jpg)
A long series centre drill was then used to spot thru onto the second part of the casting.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT36.jpg)
The hole was then drilled using a long series drill.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT37.jpg)
Both holes in line. I don't have a machine reamer that will reach both holes, so this will be done with a hand reamer later.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT38.jpg)
I now moved to the second set of coordinates I had, then spotted and step drilled up to 12mm diameter.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT39.jpg)
The boring bar then came into action, and the hole was opened out to 13mm, the size of bearing supplied for the flywheel shaft support.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT40.jpg)
A nice slip fit for the bearing. Eventually, a pair of them will be Loctited into this hole.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT41.jpg)
So that is the baseplate basically finished, except for a little fine fettling and tapping one of the holes that I drilled earlier, and of course the three oil cup holes. I have already hand reamed the two cross holes.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT42.jpg)
I hope you can now see why I used the jig plate. Fairly easily, not only did I get the surfaces, top and bottom, level and parallel to each other, but also all the holes in the correct relationship and again parallel to not only each other, but to the base datums as well. So it was definitely worth doing on this build.
So the next step of the journey is to get that big lump of gunmetal into shape. I think this is one of those stages where I will have to hold the rough casting in the vice to get my first flat face, the bottom. Then take it from there.
Bogs
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Very informative thread John, as usual.
I'm coming to this one a few days after it started. The work with the die filer makes me wish for one even more. ; )
Your explanation of the jig plate use should come in handy for a lot of fellows here. I especially liked the part about
putting the casting up on studs when you were getting started. That's one for my notebook, thanks.
Nice that you are getting some shop time! Glad for that.
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Good reading. Even I am able to understand what your are explaining.
Thanks!
Eric
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I'm glad you lads are able to understand it as I go along.
I was hoping for that to happen, as it will mean I won't need as many pictures. I can just describe it in a few words and you will remember what was done from before.
Another evening only post maybe today, if at all.
John
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Thanks John that was very informative i think im beginning to understand :scratch:
cheers Graham
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John, your preperation and the DRO made short work of that base! I guess it just takes a bit more concentration if you've got manual dials but I know my dials aren't accurate so I'd have to mess on marking things up some how.
NIck
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Nick,
It is a shame that everyone doesn't have DRO's, I am lucky on that score.
But even so, I used to do a lot of my casting work on a basic imperial mill/drill with real 'iffy' backlash problems (almost a full half turn), before I fitted scales to it, and I used to use the same methods then, purely by zeroing up the handles when the datum was hit, and working from them. I found that it was accurate enough to get all the holes in the correct relationship to each other, as long as you crept up on the setting and hit it spot on. If you went past, you would then have to start from the datum again, just to make sure the backlash was taken out.
Been there, got the t-shirt AND the baseball cap.
You have to work with what you have, and make the very best of it.
John
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John,
I was going to put sliding scales on my mill but have taken the advice from people on here and my experience using proper DRO's at university and digi verniers not to bother. I think it'd be better than what I currently have, but not enough to justify and the extra for a proper DRO would be well worth it. So I'll wait until I can afford a proper one with glass scales. Not sure whether to put money into a DRO, or a rotary table and QCTP next.
I have come to the conclusion that on my machine, there must be a pitch error in the screws. The handwheels work ok for small movements but if you have to wind something on a few inches, the error gets greater and greater!
You're right, I'll make the best of what I have. I hope to have the all singing and dancing stuff one day but for now I need to improve my skills by a long way to justify anything like that I think! The other argument is, is it worth putting on my machine, is it good enough.
Looking forward to the next post.
Thanks
Nick
-
If things are that critical Nick, maybe you could cobble something together with a bit of ali plate and some magnets, and get a digivern on there as a temporary fitting.
I personally, thru experience, wouldn't recommend the scale type of DRO's, except where there is no swarf or liquid, say on the quill. I fitted them in the very beginning, and with all the messing around and changing them, I could have bought a full blown glass scale one with the amount of money I spent on them in the two years I had them fitted. I used to have to carry spares scales in stock, as they would go down for no reason, half way thru a critical job.
John
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Nick - it sounds like you've got a metric screw & imperial dials - or vice versa. I don't know what mill you have, but it might be worth seeing if you can hunt down a set of alternative dials?
John - this is a fascinating build, I'm watching it with great interest. The more you show, the more I feel my slowly growing machining skills might be up to building something like this. So, thanks for that!
One question - can you tell me some more about this cutter:
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT17.jpg)
It looks almost like a T-slot cutter to me (only deeper), but I'm sure it's not...
-
Ade,
if I remember I'll take some pics and show you them tonight. Think they are both metric and imperial, it's like a chester century.
-
Ade,
I thought I had given you one of these cutters, almost everyone else that visited got the offer of one, shame I don't have any spare ones left.
They are a special solid tungsten end and face cutter, just like the larger diameter ones that look like large slitting saws. These are designed to rip thru hard materials like nimonic steels, but are accurate and sharp enough to take a wisp off, which is the way I use it, in both planes. It can reach down a face where a normal end mill can't get, by taking a few swipes at it, I can face an end by about 6" deep, as the cutting face is just larger than the outside collet.
It really is too large for a normal collet to hold in my machine, I think 1.125", I am limited to 1" normally, so I have to use a special outside R8 collet to hold it, but that won't allow me to do very heavy work with the cutter, maybe 50 thou max cut in steel before it starts to tell me enough is enough.
I wouldn't say working from castings is diffiicult, it is just you have to treat them in a slightly different way than when making from bar stock. Once you get the basic understanding that nothing you will get hold of will be either square or flat, then you can start to work accurately with them.
Parallels, a DTI, a small level and machinist jacks will become your best mates, and of course, a bit of jig plate. When I get to do my larger casting build, the vice has got to go, everything will be held down to the table on the largest bits, thats when things like machinist jacks come into play.
John
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By the by, John, what exactly is the magneto being built for, if you don't mind my asking? I have a special place in my heart for such things, and am a bit of an expert on their use on full sized engines. I also wanted to say that casting of the hopper is an absolute beauty, and I kind of hope the flames cause the paint to fall away, so it can be fully cleaned up and be a show piece in and of it's self. It is much larger than I thought from the drawings and looks great. To Nick, I used a two in travel dial indicator mounted on a magnetic base as my last resort before buying a DRO. It worked better than clamping two digital calipers on the x and y axis'.
By the way John, that was a very smooth move in the way you got all your horizontal bores in line, and done exactly right, that jig plate worked great. The fact that it remains a good piece of "jig plate" or a spare piece of metal when you're done only makes it practically free, as a jig. Your pictures make this a great build log too. :beer: cheers, mad jack
-
Jack,
The magneto will be used on a R&B engine that I bought the castings for last year and Rob is actually making his own.
http://madmodder.net/index.php?topic=3137.msg34848#msg34848
It will end up something like this, mine will have 2x9" flywheels instead of the one 12"
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/RB.jpg)
I'm glad you liked the way the jig plate worked. The R&B will have the same done to it once the base is flattened level.
John
-
Mainly a load of piccies tonight, and only a bit of machining.
These concern the next part to be machined up, the water hopper.
Even though it looked OK from a distance, when I got up close and personal with this casting, I was a little disappointed, as will be seen. I spent nearly an hour, trying to make a descision how I was going to machine it back to how I wanted it. At least one specific face had to be machined perfectly square to the foot, and then bored for the cylinder.
As you can see by the fettling marks, this side has an outwards bulge, and when handled, is more pronounced than shown on this photo.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT43.jpg)
As can be seen from this shot viewed from the side, the shape is more like a leaning parallelogram rather than an oblong.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT44.jpg)
When viewed from the top, you can also see that it tapers from one side to the other.
Luckily, although in parts, the casting is under nominal size, there is enough meat on it to get it all square.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT45.jpg)
I decided the best place to start was the already fettled base, which was reasonably flat, so it was gripped in the vice with the base set level to the table.
I just needed to make sure the cutting forces were kept as low as possible.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT47.jpg)
With a bit of extra support from the backstop, I used my flycutter, cutting in one direction only (towards the backstop) and with only a 0.005" cut, the base was cleaned up after a couple of passes.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT48.jpg)
This shot shows just how much inwards lean at the top there is on the sides. The next cut has to be getting the side face that requires boring square to the base.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT49.jpg)
The casting was set up again in the vice with the base sticking out.
By using a 3 2 1 block and a nut and bolt just slightly smaller than the holes in the block, I jacked the base end up so that the base was perfectly square to the table. Hopefully it will remain in that square position while the face is machined. The block and jacking screw were left in position to help support the part.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT50.jpg)
I tried to skim this unfettled face with my flycutter, but the skin was a little hard and didn't really want to cut. You can see by the machining marks just how far out this face is.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT51.jpg)
So I resorted to one of my favourites, a 16mm razor sharp cutter. This went thru it like it was butter.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT52.jpg)
This slightly fuzzy shot shows just how bent the face was, and this isn't down to full cleanup depth yet.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT53.jpg)
After going down to just over 60 thou, I had the face cleaned up, and yes, it was perfectly square to the base.
Now I have these two faces, everything else will be an easy job. Even though the angles are slightly out to each other on the two angled faces, as of yet, I have decided they won't be machined, and left as cast.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT54.jpg)
To me, it is looking better already.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT55.jpg)
I hope to finish this part tomorrow, then this build has to stop while I get a couple of private jobs done.
Bogs
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That's looking good John! :thumbup:
I regularly used to mill fabricated drill rig sections. The welder's ideas of straight and square, were nothing like mine! :bang: :bang:
Machining straight and square. Leaving an unmachined witness area as necessary, sometimes almost amounted to alchemy....... :med:
David D
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John, the hopper does look way better than when you started with it. I remember now why I got frustrated with the sweet pea castings. The material was ok but the shape of the bits weren't as good as they should have been. E.g., for the pony wheels the flange that was cast in was useless - there was so much material there it all had to come off, which infact meant doing it with castings was pointless - it would have been cheaper and easier just to use round steel.
The cylinders to me look the same - I could just make them from a square block of cast iron, the only advantage is there is a core down the bore (that won't be anywhere near in the right place though so would have to do Stew's trick) and a radius on the outer so less material to remove, but these are outweighed by the fact that there are no datums and it'll be difficult to hold.
Obviously that hopper is hollow and has a bit of shape to it so it'd have been a huge job to make from solid or fabricate. I think you've done it in the best way possible. :thumbup:
Nick
ps that gas engine is a beast, must be capable of real work.
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David,
I know exactly what you mean.
Unfortunately, I am the sort of person who demands excellence from myself, when really, on a job such as this, it could be a little more haphazard.
But on this particular casting, this squaring up and flatness had to be done this aggressively on these two sides, the whole of the engine depends on how square the bored hole is. The top will also get the squaring treatment, as I have a bit of a bling plan for that, but the opposite side to this machined one, I am going to see if it can just have a recess cut square and level, so that three sides get left with the rough casting faces on them.
Nick,
The gas engine isn't designed as a model, but a full sized 1 to 1 working engine based on the sizes of portable engines of the time it is supposed to represent. Just like jobbers who do work now, they used to carry their small power tools around with them, and so the power souce as well (instead, we have the modern day battery packs).
John
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Ah right, didn't realise that John. Thought it looked more complex than most models though so it makes sense now.
-
The final bit for this week and at a good stopping point.
Last time I had got the two faces square to each other and nice and flat. This time is getting the third face square or parallel to the other two.
This is the standard set up technique, one good face down and tapped onto a pair of parallels, with the other square and flat face against the fixed chuck jaw. A piece of soft material, in this case ali, is placed between the moving jaw and the fourth rough side. Doing that puts all the pressure onto one small point and takes up some of the irregularities on the job. You don't want to go putting on heavy cuts while in this sort of setup, in fact, I changed my normal cutting direction, from X to the Y axis.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT56.jpg)
The top surface was soon cleaned up.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT57.jpg)
I need the big offset hole in the top cleaning up for a feature I will be adding, so the boring head was roughly centred and set to work.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT58.jpg)
This is as far as I want to go with this piece at this time. It still need a few small holes drilling, and boring for the cylinder sleeve. But I want to wait until that is finished first, as the boring is a more controllable exercise than bringing the sleeve down to size.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT59.jpg)
I hope to be restarting this post later next week, depending how I get on with the Minimag build.
Bogs
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Looks great Bogs, I'm folow you'r log with the greatest interest. :clap:
-
Squared up. Centralised. Sorted..... :wave:
Able to be comfortably set aside. For later, easy pick up and resume...... :thumbup:
A good satisfying feeling! :D
David D
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Saw,
Glad you are enjoying it. I will soon be onto the fiddly bits, that is the part I like the most, and where I hope to leave some of my bling ideas. I hate engines that all look the same, with just a few little changes, it becomes personalised.
Dave,
You have got it spot on, just like I always like to leave a break in a project, pick it up and you are into it straight away.
John
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Looks great John, it's without a doubt already looking like the best version of this I have seen.
My engines usually look different because I use what I have to hand or make it easier to make! The only differences on my poppin are slightly smaller flywheels but I put 6 holes in them too, I prefer the look. It has less fins as the grooves are the width of my parting tool, piston design is different and graphite and I have omitted radii and base as I feel they are unnecessary extra work!
Can't wait to see what you have planned here, will pick up on your minibar in the mean time though.
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Hi John, that is a fine looking engine you're getting ready to build, to go with the minimag, appreciate the picture, worth at least a thousand words. I truly admire the work you've done on this build, it's coming along very nicely, well planned out, and coming together very nicely, that job on the hopper worked out well, and should have the cylinder in the right place when you've bored it, and the engine ought to be able to do some work in its own right. are you doing a build log on the minimag? I for one, would be highly interested in seeing it, and I suspect there are others lurking out there who would like to see it done up. Now I am also looking forward to your build of the R&B engine, when its time comes. I'm really looking forward to seeing this engine running, it looks to be something with some power and stamina, with that hopper to cool it, and the secret plan you have involving the bored hopper top. :poke: :beer: cheers, mad jack
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Nick,
I'm not doing a lot to the engine, no reshaping of major parts. Just fitting a nice filler funnel top to the hopper, to get away from the squarish shape and make reshaped rods, rather than the straight bits called for on the plans. As long as the pivot points are in the same positions, and nothing catches anywhere, then almost anything goes.
Thanks Jack.
I have a couple of private jobs to do, and once those are completed, I will be doing a full build on the minimag. I had a first look at the plans last night, and also the preliminary build instructions, which require following as close as possible to prove them. Looks like I will have to find the swivel base for my vice that I dumped somewhere in the back of the shop, I've never had to use it before.
The R&B will be many moons off, I have to complete all my backlog jobs first.
John
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....... will pick up on your minibar in the mean time though........
Nick - is that a Freudian slip? :beer:
- are you in fact referring to the the minimag ?
Dave :coffee:
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should look great john. Dave, damn that predictive text ... In actual fact I've been tee total since 30th Dec !
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Looks like you're having fun John :thumbup:
Totally :offtopic: but... Just catching up on all the latest bits I want to.... tried to look through a few threads over the last few nights and found myself waking up with a bad neck in my Comp' chair :palm:
I'm actually experiencing my first free evening in what seems like a month! :ddb:
Looking forward to seeing the rest take shape.... I'm still not sold on these castings though. It does look like cast iron is very messy and the shapes can be seemingly very complex to machine when compared to bar stock. I am obviously aware of the ease of creating a more complex part though.
Still plenty of time to experiment someday myself though. Threads like this will come in very handy at that point :)
Ralph.
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It doesn't seem like three weeks since I dropped this post to get on with the Minimag build.
But anyway, back I am, and ready to pick it up almost from where I left off.
The magneto build left me with a bit of a bling bug to get out of my system, so this is a little diversion that isn't shown on the plans.
Some of you will recognise this bit of brass left over from the swing up threading post, but the threaded bit on the end is just perfect for what I want.
I just took the thread down until it was cleaned off.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT60.jpg)
A quick change of tool and I had a spigot of the right size formed on the end.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT61.jpg)
A large profile tool soon had a nice radius formed.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT62.jpg)
Drill out the end a bit.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT63.jpg)
Then opened up to the required size. All this by the way is being done by eye, except for the spigot on the end size.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT64.jpg)
The bit I want was parted off.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT65.jpg)
Now comes the experience bit. All my working life, and a bit before, I have been hand shaping parts on the lathe, using a few basic tools. The basic name for it is called graving, a basic watchmakers technique which uses shaped hand held cutting tools similar to what a wood turner uses, but much smaller. I am not using those this time, just files and a sanding block, and I use it just to give me something unique that is very quick to do.
It is not difficult at all, and a lot of lathework started off just this way, but it can be dangerous if you don't know how to hold the tools correctly, and also, you are working with your fingers very close to a fast spinning chuck, and as you all know, machines have no feelings, and they will chop you up just as easily as they chop up metal and other materials. So unless you are VERY safety conscious and scared to death of your machines because you know what they can do to you, don't even try it. I am only showing the basics here, and even though it can be dangerous, it is a perfectly recognised way of shaping items in the lathe.
First off, the part was remounted back into the self centring four jaw chuck with the bit I want to shape up to the outside of the jaws. Using hand and eye coordination, plus a boring bar, I roughly profiled the inside of the part to match the outside bit which had been machined.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT66.jpg)
Using just a few files and a sponge emery block, I blended all the rough cuts into one smooth flowing rounded shape, getting rid of all the maching marks at the same time.
A sheet of white paper put onto the background helps in seeing that everything is blended together, having just nice rounded curves with no flat spots.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT67.jpg)
A quick dose of Mrs Buff had a nice basic shine added to the part. Just before final assembly, it will be given a final deep lustre polish.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT68.jpg)
As you have most probably already guessed, this is a nicely shaped funnel for the water jacket, instead of the horrible gaping hole that is shown on the plans.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT69.jpg)
Total time, just over an hour. Time well spent as far as I am concerned
Now the bling is out of my system for now, I can get on with building the engine.
Bogs
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Lovely bling :thumbup:
-
Cant beat the bling :D
Lovely flowing lines on that funnel :thumbup:
Tim
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NICE! :thumbup:
David D
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Many thanks for the good comments gents.
I don't know if I put people off by my comments about hand graving and the safety issues, but in all honesty, if you care to take the time and train yourself to work very closely to the chuck, it can be a very rewarding experience.
I have forgotten the amount of boiler funnel caps I have made for people, but something like that can really put the finishing touches to a steam plant or a distinguishing part for an engine can really set it out from the ordinary.
As I have shown before, where I turned up shaped steel handles, they are not available commercially, but if you can have a go yourself, almost any turned shape is possible. From little hand turned finials in place of nuts as on my mine engine, to a spinner shaped cone to fit my small turbine and elbow engines. All done in a matter of minutes, and totally unique.
For my graver rest, when I use a graver, I just mount a bar in my toolpost and bring it close up to the job, so no special lathe fitments are required. BTW, great gravers can be made out of worn out files, just grind up the shape you require on the end and leave most of the teeth on there, they give a good non slip surface to hold onto, but make sure you leave the original handle in place.
John
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Very nice John, have often wondered how people make the fancy shapes on funnels, etc. You're right, it was a bit of a gaping hole on the top of that casting before. Very professional looking now, I love it!
Nick
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Hi John, glad you were able to get that "bling drive" out of your system. I guess hand tool work on lathes is something for old folks to remember, it was where I started on both a wood and metal lathe. It's not that dangerous, it just hurts sometimes, like when I smashed my fingernail off when one of the chuck jaws hit it. Wasted almost ten minutes getting a clean rag taped around it so it would quit leaking, and just from using a file :lol:. That funnel looks great and will certainly be unique, it fits the whole of the engine very nicely, and does look much better than a plain old hole. I'm really looking forward to seeing and hearing this engine run, great work at making it look easy. :nrocks: jack
-
Good to see you back onto this engine and giving it your own touches, the flared spout gives the hopper a lot more caricter.
As John says provided you are careful and think about what you are doing hand turning can be quite rewarding and is not at all hard particularly in a material like brass. Its a very good way to refine curved forms, these (http://smg.photobucket.com/albums/v156/jasonballamy/Fowler%20A7/?action=view¤t=PICT0153.jpg) bits for a traction engine whistle were all hand turned using a 3/16" dia scraper. And once you are confident with hand turning you won't have any worries about trying metal spinning.
J
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Actually Jack,
great work at making it look easy.
It is as easy as it looks, I'm sure if I can do it, so can everyone else. I'm no superman and also I've got a gimpy right hand and arm.
Jason,
Nice looking bits, easy isn't it?
I have never tried spinning anything over a few inches diameter, but one day I just might.
So today, after playing about with a new bit of tooling I have aquired, there wasn't much time for machining, but I did get a little done.
The next bit of natural progression for me was to get the cylinder made, and a nice big lump of cast iron was supplied. In fact, enough to make two, if I don't get the first one right.
It was mounted up in the chuck, the free end gently centre drilled and a rotating centre was used as support. Then it was just a matter of cutting it down to size.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT70.jpg)
By taking things steady and slowly, the outer surfaces were brought down to exact sizes and lengths.
The machined up bit was then held in the chuck while the rest was parted off.
But due to an unfortunate accident, where I couldn't take the weight of the piece that was being parted off correctly, it trapped my favourite parting off tool and snapped the end off. Back onto fleabay to find a replacement. You win some, you lose some. I still have the left hand version of the same tool, so I will be OK until I find another.
Normally for taking off such a large lump I would have used my power hacksaw, so it was my own fault for trying to do things too fast.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT71.jpg)
As you can see by comparing it to the digivern, it is a rather large cylinder.
I checked to see if I had enough length on my boring bar to get the bore done, and it looks like I will get away with it, if I take it steady.
The 4" long lump at the side was the piece that trapped my parting tool and broke it, all because I couldn't support the weight.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT72.jpg)
Next time will be getting a big hole stuck thru the shaped up lump of cast iron.
Bogs
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This project got right back on top after the Minimag, John. Good you are able to keep at it a few hours a day, now.
The hopper topper looks right nice!
-
I forgot how big that engine was John :jaw: what is the bore and stroke? Good to see you straight back on this.
Nick
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Thanks Dean and Nick.
If I don't continue going into my shop, even if only to do some reading, I am very reluctant to get back in there, so I just keep going.
Nick,
1" 5/16" bore by 2" stroke
John
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There's one consolation. It will be a heck of a lot lighter once it is bored out.
Dave.
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I know what you mean, it's much easier to sit in the cosy house and not get dirty, good on you. :thumbup:
-
As David said, it will be quite a bit lighter once it's bored and honed out. Awfully nice they gave you a piece to make a cylinder for another engine, I'd say that's quality in the kit, for those who question taking on castings. Nice work, all around. jack
-
Actually Jack, the extra material is to make a couple more pieces that are required, but there would be no trouble making them up out of normal steel if I used it to replace a buggered up cylinder. It is for that reason I am making the cylinder first, just in case I need the option.
But I needn't have worried, making the cylinder went very smoothly, but I might still keep that piece of cast and make the bits out of some scrap steel I have, it seems such a waste of a good piece of precious material.
Away we go, my way of boring a cylinder.
First off, I am using a four jaw self centring chuck, not a 4 jaw independent. I find they are a little more accurate than a normal 3 jaw.
One of the first things you will notice are the brass shim protectors, you could use cut up drinks cans instead. Cast iron, although fairly hard to penetrate can have the surface bruised very easily by unprotected jaws, these are used to help prevent that. There is no need to go to white knuckle tightening up, they grip rather well without going that far.
The flange was faced to correct thickness.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT73.jpg)
By using different sized drills, I gradually remove most of the material to come out of the bore.
I left 3/16" to bore out. You can go much closer than that, but I like to use the run up to final size to gauge how the bar is cutting. Writing down the cut put on and seeing if it matches with the amount taken off.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT74.jpg)
The boring tool was set up in it's holder. Making sure that it will go all the way thru the part. I also set up the saddle stop so that it works just after the tool has gone all the way thru.
This is really sticking out a bit more than normal, but this is a 16mm diameter tool and I have found that they are more rigid than a normal steel one of the same size, so if normal cutting pressures are kept low (no big depth cuts) then everything will be fine.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT75.jpg)
So the sleeve was remounted into the chuck, but using a slightly different method.
The flange goes fully up to the jaws, to stop the sleeve being pushed inside the chuck as I put a new cut on. Secondly, the protectors are still used, but the jaws are only tightened just enough to stop the part spinning in the chuck.
If you tighten up too much, the outside walls will be pressed inwards and when the boring bar takes it's cut, it will be off the metal that has been pushed inwards and you will find that when the chuck pressure is taken off, you will end up with a triangular(if using a 3 jaw) or square (if using a 4jaw) shaped hole, not perfectly round. I hope you understood that.
If possible, I always try to bore thin wall items with the bored part being outside of the chuck jaws.
Anyway, back to cutting out this hole. I rough cut out at 0.025" cuts for the first few, until I got within say 15 thou of required hole size. Then remove the material until it leaves about 0,002" to be removed. The closer you get to size, the finer and slower the feed you use.
I do the final cut, measure that it is either spot on or very close to size, then using a very fine feed, take another half dozen cuts with no more cut on at all, just using the same setting as the final one used to get down to size. This is to take off any material that wasn't cut because of the tool flexing as it went down the bore.
All this lot took well over an hour, but hey, the job isn't going to get up and run away, so time shouldn't enter into the equation, other than the longer you take on it, usually the better results you get.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT76.jpg)
The bore, measured at either end was exactly the same, one thou oversize, so no tapered bore. I suppose I should have used my deep bore gauge as I was doing the job, but I couldn't be bothered to unpack my instrument cupboard to get to it.
The surface finish was smooth as silk. I love working with cast iron for that very reason, you can get fabulous smooth finishes on it.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT77.jpg)
The last pic shows the sleeve sitting on a bar of metal. Cast iron again, and that will end up as the piston. A job for next time.
Actually, the instructions that came with the engine suggests honing the bore at this time. Personally I think that is the wrong way to go on an engine such as this, so after the piston is brought down to size, it will be lapped in with the cylinder bore, that will give an even smoother and less friction of fit than honing could achieve.
Bogs
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lovely work Bogs as always.
I love working with cast as well but its damn dirty stuff abd a bugger to clean up after
Graham
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Nicely explained John. :clap:
I could almost smell the c/i dust..... :thumbup:
Took me back to my apprenticeship days, and several years working full time on castings.
Certainly don't miss that black dust.....It got everywhere! ::)
David D
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DKM,
I am using standard bits that are obtainable anywhere. For people working at home, I find that there is no need to go to the trouble of obtaining anything special.
Also, you will find I very rarely, if ever, quote numbers and letters etc in my posts, purely because they only confuse people even more. If it can't be kept relatively simple and easy to understand, I don't show it.
Dave and Graham,
I am very lucky, my wife cleans up after me, so as long as she can reach the shop vac, I don't worry about the mess. When I have finished with the CI maching tomorrow, I will call her in.
John
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Cylinder looks good, John. It's nice to see a more experienced fellow do things the way I do it.
Makes me think I'm doing my own stuff right. : )
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Nice work John,
That bore doesn't look to me like it needs any lapping or honing to be honest.
-
Thanks Dean and Nick.
Dean, maybe I am doing it the same as you, rather than the other way around, and Nick, the surface finish on that bore has a long way to go, it should come up like dull chrome eventually. Then you know you have a very friction free surface, ideal for this type of engine, whereas with an ic one with metal rings, you can leave it rough and let the engine bed itself in whilst running.
Mind you I don't suppose you remember the signs on new cars from the 50's & 60's - RUNNING IN, PLEASE PASS. Even after running in correctly, 30,000 miles and it was due a rebore. Crappy metals and manufacture, even worse lubricants.
John
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John,
On my ridders engine and poppin I didn't lap any bores or polish any pistons and they seem to work well. I am sure you will extract superior performance but not sure how much better.
Some people seem to really go over the top on lapping in my opinion.
Good point about car engines of old, I guess a car is lugging a lot of weight around though, they have serious stress on them and at an average speed of say 30mph that's 1000 hours of running. I doubt my engines will see more than 100 hours of ticking over over the course of my life!
Nick
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I'd definitely agree with your final finish desire, it does make a substantial difference in useful power, and longevity. The issue with rings was the lack of full understanding of the loading, and the need for the rings to be substantial harder than the bore, as the contact surface of the rings is a factor of far more than a hundred to one, and cast iron has those nice little nodules of carbide in it. Ring wear today is mostly due to exotic additives in the ring material, and partially due to better control of surface angles and contact surfaces designed to follow the twists and flopping caused by friction and direction changes, with angles designed to work with the natural forces on the ring, rather than trying to counter them, by making it more rigid. I use several different kinds of rings in rebuilding Harley engines, each brand of which claim to have solved all the world's problems with new technology, but I never know what the rings will look like when I order them until I open the package. There are three or four differing engineering perspectives on rings, all of which are at least somewhat contradictory to each other, with the major difference being in minute differences in cranking pressure and final horsepower, all of which tends to be accademic to the mechanic and the owner, except for racers, where it does really matter.
Lots of machinists don't know that good quality cast iron can be brought to a mirror finish under the right conditions, and that, coupled with accuracy in roundness and taper can allow an engine to run at full temp with less than half a thousandth clearance if the piston and cylinder are iron. I've found delrin does an excellent job in carrying lapping compound for a final finish in iron and is cheap and easy to get, and easy to throw away after its dead and gone. :beer: cheers, jack
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Nick,
I will most probably spend more time on getting a good finish between the bore and piston than I have spent making the two parts.
To me, they are the most important part of an engine, and getting it right first time will eliminate any queries about them when it comes to get the engine running, if there are any problems.
Because there was so little spare length to hold the billet in the chuck (3/16") to complete the piston by normal methods, I am using a feature that is normally put in last to actually help me make the part. When you see the finished article, you will see why I went down this route.
First off, I did a fine face off on the end, then drilled and tapped a 3/16" x 40 tpi thread in it (normally the last bit to do). This is going to be the main datum for the whole machining exercise.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT78.jpg)
I now went over the whole billet, rough skinning it down to within about 0.050" of finished size all over.
This is removing metal from the other end of the billet.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT79.jpg)
The O.D. was taken down in two stages.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT80.jpg)
The final part was to remove the bulk from the inside.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT81.jpg)
So this is what I ended up with. I now need to be able to hold this fairly rigid while I bring everything down to size.
Time to make a mandrel.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT82.jpg)
Using a piece of bar end, I turned a spigot sticking out on the end and then faced the end off smooth. The spigot was then threaded 3/16" x 40 tpi.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT83.jpg)
The part was then screwed on tight onto the spigot screw and faced end.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT84.jpg)
I need to get the heaviest of the machining done first, as the screw will be gradually shortened to a couple of threads by the time the centre is bored out.
First off, the piston was brought down to exact length.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT85.jpg)
Followed very gently by removing all the inside of the piston by boring. You can just see at the bottom of the hole where the screw has been shortened by the boring exercise.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT86.jpg)
The OD of the piston was then brought down until it just fitted inside the bore, just a nice push fit.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT87.jpg)
You can now see how much metal was removed, I suppose because the piston needs to be very light just so that friction and reciprocating forces don't get too high.
If I had tried to hold this with a normal chuck, I would imagine it would have collapsed.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT88.jpg)
My mic said I had 0.0006" clearance (about 0.015mm). That will be spot on for when I start to lap the piston to bore. Hopefully I will end up with about 1 thou clearance (0.025mm).
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT89.jpg)
You can also see that the bar end will act as a perfect piston holding handle for doing the lapping with.
Bogs
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I like the idea of the spigot with the fat end for supporting the piston. A good multi-task jig, John.
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Jack,
Sorry I didn't answer you before. I use Delrin sometimes as well, it is very easy to embed the cutting agent into it's surface with a piece of hardwood. But I don't thro it away afterwards, I just do an outside skim on it and it can be used for something else.
These pair though are going to be lapped together. I find cast against cast gives a lovely finish when final lap is with something like jewellers rouge or toothpaste.
Dean,
I suppose no matter which way it was done, some sort of mandrel would have been required. this way was the first to come to mind, so it got used.
Now the dirty work begins with the lapping.
Almost everything after that is straightforwards machining and sticking or silver soldering together.
John
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John,
Great work on the piston, I remember when I first did my jan ridders piston without hollowing it out and I believe it did make a difference. The engine wouldn't run with the extra mass. I got away with just putting the slot in the graphite as it was so much lighter anyway.
I don't disagree that correct lapping must improve the performance of such an engine. However, what I am trying to say is, I have proved although it's obviously a critical fit, it's not as critical as people think to get a running engine and that goes for flame gulper, stirling or whatever. I'm not saying my surfaces had a poor finish, they were as you said - done on the finest feed and very smooth, could not see (by eye) or feel any ridges. It'd be interesting to try and quantify any differences in the two methods.
I guess the difference is, I'm aiming for a much lower standard! I'm happy with an engine that will run well for the moment. The easiest and quickest way I've found of doing that is by reaming the bore and leaving the piston as turned from the lathe with a fine feed.
Nick
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Hi John, and greeting to all reading, I put my emphasis on lapping because I use that as the means of fitting solid, closed end connecting rods with pressed in hard bearing races that Rockwell about a C-63-65 out of 10100 Torrington bearing steel, and lap for oversided rollers which come in increments of two tenths over, up to a thousandth, and then in one, two and three thousands oversized, before one needs to press out the races and put new, undersized races in. The lapping is done with an expanding cast iron mandrel, and I've made replacement mandrels for rods, for the pinion side race on the primary engines I rebuild, having worn out the original lap heads. Using the same compound on say delrin first, using the long lap and short lap method, on a cylinder, it can be brought to an almost mirror finish, which is achievable with finer lapping compound and finally rouge as you suggest. Having fitted rods for many decades to existing crankpins, using bore guages, and finding the quality of finish being in the micron range, I have come to expect such a finish after lapping, and found one can get pretty large without going to rings, and getting full compression, particularly if you have a tool post grinder for finishing the piston, as that eliminates all but the final lap on it. I like less than half a thousandth up to an inch, with steel or cast iron in cast iron cylinders. I find it hard not to lap to such standards on anything open to it, having done it so many years on the machines I've routinely been rebuilding and having both the full equipment and experience. I too dispose of the delrin only after it has been cut down to the point there's nothing small enough to lap with it anymore, but being cheap to buy in a stick makes it handy, and it cuts very accurates, and holds on size unchanging with temperatures in the normal range. It also is the only real method of using glass cylinders with any expectation of accuracy and close fitting pistons, and allows fitting less than a tenth of a thousandth with graphite pistons if a lathe will hold that for the short length of the piston, which most lathes will. Excuse me if I took over your post for a minute, John. cheers, jack
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John,
The piston and cylinder look fantastic. They look silky smooth.
John\Jack would love to see a thread about lapping cylinders and the techniques.
Eric
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Nick,
I'm not criticising anyone about their methods at all, and as you know, I wouldn't do that unless it was unsafe to show. I am just showing the standards I always try to achieve, it is a personal thing on my part.
People can emulate or not, that is their decision. But until they are shown or told the choices, some of them most probably don't realise there are any choices to make.
Actually Eric, photos, especially with flash, usually show surface finishes worse than they really are. This pair are actually a lot better in real life than what is shown here.
If I wasn't so fussy about any work that I do, they would most probably run plenty good enough as they are.
With regards to showing lapping etc. The US lads have a definite advantage over me in that department. They have retail access to very cheap soft laps, whereas in the UK, although most probably available, they will be neither as cheap or accessible as the US ones are.
So I personally have to use old and trusted methods for achieving what is required.
John
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This is so very nice. :clap:
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John,
I agree, and it shows in your finished work which is 2nd to none. Good point, I didn't realise there was a choice and I have probably made many a cylinder and piston worse by trying to lap it the wrong way. It sounds like your lapping method and otheres discussed in this post are robust, tried and tested ones though so I will be trying it again at some point. :thumbup:
Nick
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Hi John, I'm actually a bit surprised, I would have expected you to have similar access to what we have, and actually would have expected to more, given model engineering has had a stronger following in the UK than here until lately. I routinely get consumable things like lapping compound, sticks of various metals and plastics, and screws and such from McMaster-Carr, a national supply chain, and would have expected similar availability there. I use fine valve grinding compound for my first lapping, it's listed as 320 grit, and then I can choose from a five hundred grit, and go forward, or trade off to diamond lapping compound (the other is silicon carbide), and get down to the kind of finish necessary for diesel injector plungers and the like. On my "ducky" flame sucker, I used the fine compound, and then went straight to simichrome polish with rouge rubbed onto the coated piston and rubbed inside the cylinder, lapping with changing the compound about four or five times. I believe it came out with about .0005 measured clearance. The piston was filed as the last step in the lathe with a six inch smooth file, taking off about .0002 thousandths, before moving on to lapping, with about three or four tenths clearance at the start of the lapping process, but a substantial change in surface finish by the end. In my next order I will be getting a can of the five hundred grit, as I can use it more often, now that I'm modelling, and doing smaller work. If I couldn't get the delrin or something comparable, I'd use hardwood dowel, machine half away for a section, make a half to fit in, and the dowel the two together, using paper to go between, and increase the diameter, oak and walnut are good because they have an open grain that holds lapping compound well. That engine is coming along nicely, and should be ready for a video pretty soon I expect. Looking forward to it. :nrocks: jack
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nice build John :clap:, cant wait to see the end result,
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Jack,
I was on about the soft copper expandable laps that you lads can get. Load 'em up, and away you go.
But I always find that I get much better finishes and fits by lapping the two together from the start. I normally only use a seperate bar for getting tiny tapers out of the bore.
Scrapman,
Neither can I wait to see the end result.
A couple of years ago this would have been done and dusted in a week, but now everything is done at a much more relaxed pace.
I get a lot more enjoyment for the buck.
John
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bogstrand A couple of years ago this would have been done and dusted in a week, but now everything is done at a much more relaxed pace.
Yes thats my thougt's to. Take it easey and enjoy the building. :thumbup:
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It was dirty work today, lapping.
I will just explain something that I haven't shown.
When the unlapped piston was pushed thru the bore, I noticed that about 2/3rds the way up from the end (opposite to the flange end of the cylinder) I noticed there was a slight binding up between the two parts. If I had had not been so lazy and used my bore gauge from the start, rather than using an internal mic at each end, I would have picked this up and taken a few more non feed cuts when I was boring the cylinder. As it was, I used my bore hone to straighten things out. There was most probably only about a tenth to be removed, and it only took a couple of minutes to hone it out.
All operations were done on the slowest setting my lathe will go, 65 RPM.
After that, it was just a matter of starting out with a bit of diamond paste gently spread onto the surface of the piston. I wouldn't recommend using diamond if it was a non ferrous bore or piston, as it tends to permanently embed itself into the soft metal surface, so if it isn't all completely removed, it will carry on wearing away the bore as the engine is running. After a good wash down with thinners, I used a commercial chrome polish, cleaned down again, then finished off with rouge paste.
These operations took just over an hour, gently rotating the sleeve up and down the over the piston in a sort of figure of eight movement until things start slackening off and getting easier with each different compound. I recharged each compound about 3 or 4 times, when it started to get filthy loaded with cast iron sludge. You have to make sure that the whole inner surface of the bore is lapped to the outer surface of the piston.
In the beginning, the sleeve had to be held fairly tight to stop it rotating with the piston, but as things went on, it got easier to hold. The final lap was actually done with just one finger pressure moving the sleeve up and down.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT90.jpg)
I tried to get a flash shot showing the semi chrome finish on both the bore and piston, but failed miserably. Because I am scared of boogie men, I won't go out to the shop in the dark to take another picture.
Anyway, another take my word for it, they were s-m-o-o-t-h as silk.
In fact, just by gently sucking and blowing on the flanged end of the cylinder, the piston went up and down in the bore.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT91.jpg)
I have taken a shot of the bits and bobs that I used for the exercise, and I will try to explain how the hone works.
On the left is my commercial cylinder hone, designed for things like brake cylinders and small i/c bores. I paid less than 20 squid for this off the net, from a motor factors. If you buy one from a model engineering supplier, they will cost you double that, for exactly the same thing (or even less contents).
This one will work with bores from around 3/4" up to about 3.5". You can buy extra stones, both harder and softer grades in different lengths, to cater for different materials and depth of bore. I have found the ones supplied have done a great job on all the different bores I have honed.
The way they work is that when the stones are fed into the bore, they lie flat against the inner surface, and by gently rotating in the bore, and moving it in and out, as I did my lapping, it will gradually make the bore perfectly parallel and round. In use, you keep it well lubricated, I use my general purpose hydraulic oil that I use on my machine for the gearboxes and local lubrication, and by adjusting a thumb screw at the back of the spring, you can make the stones cut harder or softer. The closer you get to perfect, the softer you have the setting.
These hones are not really for getting a very smooth bore, but they will do if adjusted correctly, as I said, they are used for getting things straightened out. You will find that after use, if you have followed the movement regime I mentioned earlier, there are minute scratches in the bore face. As the engine is running in, oil will get trapped in these tiny scratches and help prevent the piston seizing in the bore as the two bed in together over time. Eventually the scratches will be worn away and you will end up with highly polished bore and piston.
From certain model engineer suppliers, you can buy casting kits that when made up will do the same thing for the outside of the pistons, they are called external hones.
The lapping I have done does away with this engine running in period, and the engine should be able to get up to full speed from the start.
On the right hand side of the pic are the three compounds I used for lapping. The green stuff at the back is my own diamond lapping paste that I made up a few years ago, and it is used to get most of the sleeve to piston undulations removed. Next one down is a commercial chrome polish. This is for getting things started to be really smooth, then followed by the jewellers rouge which imparts a nice polish to both surfaces.
People use all sorts of different compounds for lapping, these are just the basic ones I use. If I was doing a non ferrous bore or piston, I would actually use an aluminium oxide grinding paste (the stuff used for grinding in valves on a car) instead of the diamond paste. The ali oxide actually breaks down into a harmless sludge during the lapping process, so is easily washed off, and causing no further wear to the parts.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT92.jpg)
So that is the cylinder bore and piston finished, except for drilling a few mounting holes. That means I can get back onto making things.
So you have to imagine what I look like now, hands filthy, embedded CI dust in the pores, the front of my white t-shirt covered in the same stuff, and a ring of dirty oil around my lips, from sucking the piston in and out, and of course, once John S finds out, he will be there with all the Al Jolson quips, as usual.
Bogs
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Hi John
Cylinder hone not this one is it ??
http://www.rapidonline.com/Tools-Fasteners-Production-Equipment/Automotive-Products/Vehicle-Service-Braking/Cylinder-Hone-Kit-4-in-1/303648/kw/hone
Saw it some months ago, seemed el-cheapo :scratch:
So, didn't get one ....
BC
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That's the one Dave.
I've had this one a few years and it is well up to the job. I put mine in the lathe chuck and drive it from that, but you can use it with an electric drill, but keep the speed down a bit.
Once you first get it, you will go cross eyed trying to figure how everything goes together, but once you have the knack, dead easy.
John
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Hi John
Oh Bu99er .... I have one from Polly, about 7/8" to 1 1/8" or so ... it was about the same price as that complete kit cost, ( as indeed, you said ... :(
So I assumed the kit wern't up to snuff ...
Grrrrrr ....
BC
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I nearly did the same as you Dave, but I did a good comparison first, as I had already seen the Polly one.
You win some.........
John
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Hi John, very good explanation of the honing and lapping process, and a good display of the tools as well. That engine should start right up from the get go, and run pretty much full speed and power from the beginning. It is awfully hard to get a good picture of the bore of a cylinder that shows the quality of the finish and the bore. :beer: cheers, jack
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Hi John :wave:, Things take alot longer with me to John, I starting to get old lol,
Ray,
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Now I have got my bit of new old tooling out of the way, I can carry on getting this engine built.
I need to find where to bore the hole so that when the sleeve is fitted, not only is it parallel to the base but also the correct height from it. The conrod has a fairly wide sweep up and down, and if those two are not correct, within reason, the conrod will catch the edge of the cylinder.
So using an old fitters trick, I filled the cast hole up with a bit of sheet lead tapped into position so that it grabs the inside of the hole. There are many other methods that can be used, bits of wood etc, but I find that this way suits me.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT93.jpg)
By using a few hand tools, and a copy of John Stevensons precision oddleg scribing calipers, I got the centre hole spotted to within a couple of thou. When working with castings such as this, that is perfectly good enough.
It took the opportunity to mark up where the faced area needs to be cut to.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT94.jpg)
Using my coaxial thingybob I soon had the centre found and the table zeroed up and locked.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT95.jpg)
I was soon boring thru both the top and bottom faces.
I did find out the the boring head actually removes double the amount that is set, the normal thing on a lathe, but no problems keeping things accurate, it is marked up in half thous.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT96.jpg)
It was soon up to a position where the sleeve could be gently pushed thru both top and bottom faces. I should have no trouble sealing the sleeve into the hopper.
There was a problem with the boring head, I had made the key handle much too small, and it hurt my fingers as I took the facing cuts. Because of this, I actually forgot to take any pics of the facing exercise.
I will soon be able to knock up a more comfortable key, and maybe another time I can show it facing off.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT97.jpg)
But it actually did a superb job, totally square to the bore, but I did have to go to 0.025" (0.6mm) deep to clean off the casting face so that the sleeve flange sat flat all the way around.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT98.jpg)
The two parts pushed together. I'm very happy with the results.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT99.jpg)
I am now in the process of recentring everything up, because if I now make the cylinder head and stick it onto these two bits, I can drill all the holding bolts at the same time rather than having to spot thru from a previously drilled cylinder head, and maybe make a mistake.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT100.jpg)
So next time will be the cylinder head.
Bogs
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Looks very well done, John. Your new big bruiser boring head seems to be working out great too.
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Hi John, that worked out very nicely, I'm envious the facing capacity, it did a beautiful job setting up for that flange. I was looking for a new honing set today, and can't find anything anywhere near as nice as that kit you showed, with the range it has. :beer: cheers, Jack
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Jack,
Amazon in the UK sell them,
http://www.amazon.co.uk/Sealey-VS029-Cylinder-Hone-4-in1/dp/B000RO7THQ
So I would suspect the much larger Amazon base in the US would do as well.
John
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John,
You've made that spot on. It's certainly the first proper scott flame licker I've seen.
Nick
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Thanks for the heads up, John, I will check with Amazon, and see what replacing my old, beatup sloppy setup will cost me. I used a ball hone also known as the dingleberry hone, to hone my oddball flame sucker, before lapping, and it does a good job setting up a good cross-hatch, but does nothing at all for straightening out tight spots or ensuring a straight bore, as it follows what is there absolutely. Are you going to put a slight spigot on the head, to locate it central in the cylinder when you get to drilling the PCD for the head bolts? It's hard to beat good quality bronze castings, when it comes to making an engine look and perform well. That water jacket really sets off the rest of the engine, and will be a major "eye draw" factor once it's complete and running. :beer: cheers, Jack
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Thanks Nick, now it is starting to come together. I am looking for parts that I am able to modify to make it look unique. There is not much to play with as some places are tight to get into, so I can't change things too much as they will jam up, but I am trying.
Jack,
I have actually already made the basic cylinder head this morning, with spigot, and I am hoping I am up to an evening session to get things finshed off in that department. If not it will be tomorrow.
The jury is still out on the water hopper. I will be distressing back the two machined faces that show that I put on to get it machined up, but as to polish or paint, I have no idea at this time. I am leaning towards paint as there will be a lot of polished bits on it when finished, and a polished hopper just might make it look too much.
John
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John, this is really starting to look like a nice piece of kit now. I'm looking forward to seeing it run for the first time (which, I'm sure, will be the first time you try it).
Also, thanks for showing all these techniques and tools; I'm filing them all away for the time I'm bound to need them... :thumbup:
-
Ade,
I'm looking forward to seeing it run for the first time (which, I'm sure, will be the first time you try it).
I doubt that it will run first time, but I am doing everything to eliminate things that might stop it running, so hopefully it will only require some fine tuning.
I had forgotten that the head had to be made before getting everything set up in the mill again, so here are the bits again. I need to take just over 1/4" off the bar of cast iron and that will then go into stock, a nice little freebie supplied with the kit.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT101.jpg)
The bar was again mounted up into my 4 jaw self centring and the head was turned to dimensions on the end of it.
I also drilled a hole in the centre, just deep enough for the parting tool to hit. That helps a lot with parting off, especially with these large diameters, the tool doesn't have to reach all the way to the middle, which is the area that cutting failure usually starts to cause problems.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT102.jpg)
It parted off just fine.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT103.jpg)
It fitted into the sleeve nice and snug.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT104.jpg)
I had a choice now. The instructions said that the end face of the cylinder head had to be as flat and as smooth as possible. If it wasn't that way, and it was left roughish, it would act like a file on the graphite block that is used as the sliding flame hole cover, and it would last no time at all.
I could either get that flat and smooth face by ten minutes on the surface grinder, or an hour with a lapping plate. I thought the grinder would be the better choice for me.
So not only was it flatted off, but it was taken down to the correct thickness, which saved another setup and facing job on the lathe.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT105.jpg)
Smooth and flat, just the job.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT106.jpg)
It was at this point I started to do a bit of forwards planning. The head required six mounting holes drilling into it, plus the flame hole needed to be machined. Once that was done, the holes were then to be transferred onto both the sleeve and the water hopper (keeping everything in the correct orientation). IMHO, a cock up waiting to happen.
So I first superglued the sleeve into the hopper.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT107.jpg)
NOW it was time to get it set up in the mill.
BTW, if you do have the opportunity to obtain one of these coaxial jobbies, I can thoroughly recommend them. This one is spot on, and has saved me hours on set up times. But they do take up a bit of throat space, so no use on the smaller mill or lathe.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT108.jpg)
The newly made head was then superglued into the sleeve, and a weight added for ten minutes, giving it enough time to make the joint.
I use superglue a lot for little jobs such as this, where there aren't heavy machining forces involved.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT109.jpg)
Using the coordinate feature of my DRO, I spotted then drilled down into the hopper with the correct size for tapping.
Then a quickie calculation and set up, I followed down with an end mill of the right clearance size for the fastener exactly to the depth of the head and sleeve flange.
The plans call for 5BA bolts, but I actually prefer something like this to be held with studs and nuts, so I am using 3mm studs, with washers and nuts, to give a nice neat fixing.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT110.jpg)
By doing it the way I did above, I could now reach down with a tap and finish off the threads in the water hopper by hand.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT111.jpg)
That then allowed me to use some screws to hold everything together, so that it could resist the cutting forces to come. The superglue was now redundant
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT112.jpg)
The flame slot was first milled out with a one size smaller cutter, the correct size one was then used. You will get a more accurate hole and better finish by doing it this way.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT113.jpg)
Job done.
Four operations combined into one, guaranteeing that everything is in the correct position.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT114.jpg)
A few seconds heat from a blowtorch soon broke the grip of the superglue, and when cooled down, it can be peeled off the surfaces with a fingernail.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT115.jpg)
These parts will now be put away for a while, as other bits need to be made.
I will make the decision as to which ones next time I get in the shop.
Bogs
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Looking good John :thumbup:
Those coaxial are very good I use mine far more than I would have thought, as you said you lose a bit of head room, but I use mine with a morse taper collet and find It gives me just enough to work with even when I use it with my RT on my X3 mill.
Stew
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Looking very good. :thumbup:
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John,
Great progress there. I found that the trials and tribulations of building and getting the Jan Ridders internal valve flame licker taught me what to look out for on future builds and my poppin did literally run the first time I held the flame to the port - it's a different engine again but I'm confident yours will as you did much more experimentation with your boxer version.
Getting exciting now!
Nick
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Looking like it's going together nicely John :thumbup:
Feeling inspired again... I really must get my lazy ass back out into my workshop (instead of typing on here I hear you say!?)
I feel myself wishing retirement to come early.... Well, I'd be happy if it came early with no complicating factors and lots of spare cash! But you know what I mean.... Time to do stuff when I'm not completely shot through work! :dremel:
I do like the idea of drilling and milling at at once to save mistakes :thumbup:
Ralph.
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Thanks gents, slowly but surely, it is getting there.
Ralph, you don't want retirement, it is not all it is made out to be.
As for getting in the shop, do what I do, a couple of hours each day if possible, make one good part at a time, and eventually you end up with what you want. In my younger days this engine would have been finished in a week, but I am getting a lot more enjoyment out of it now that I am taking a lot longer over things.
John
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Thanks gents, slowly but surely, it is getting there.
Ralph, you don't want retirement, it is not all it is made out to be.
As for getting in the shop, do what I do, a couple of hours each day if possible, make one good part at a time, and eventually you end up with what you want. In my younger days this engine would have been finished in a week, but I am getting a lot more enjoyment out of it now that I am taking a lot longer over things.
John
I've got to agree with you John, taking more time and doing it right, the first time is definitely better. I've discovered that I tend to get in a hurry and wind up having to do it over, sometimes 3 or 4 times. I'm also learning to take more time with set ups and think about tooling that will ensure more accuracy. These used to be distractions that I dreaded, but invariably I would spend more time than if I had just slowed down and done it right the first time.
Chuck
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Too true Chuck.
I went in the shop this morning with the intention of sorting out the flywheel for this engine. So because I needed to use my smaller 4 jaw self centring chuck (8 spoke flywheel) I started to prepare the lathe for converting over to a Myford nose to use the smaller chuck, then realised I could do with one of those ball race straightening up tools, so I dropped everything to do with the engine and started on that instead.
The engine isn't going to get up and run away, it will still be there to carry on with after this bit of tooling is made.
It makes being in the shop a lot more interesting and relaxing, rather than forcing yourself to get things finished.
It was the same this evening, Stew called and asked if he could come visiting. So instead of me trying to get a late evening session in, he dropped in and we had a bit of a chinwag about how his new engine is going on, and he had a look at the bits and pieces I had made.
There is a lot more to this engineering thing to enjoy than you realise.
John
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It's shaping up well, John. You do up good instructive text and explain the benefits of your steps well, too.
That grinder sure made a good job of the head. I like that!
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Ralph, you don't want retirement, it is not all it is made out to be.
Hence the little provisions... "I'd be happy if it came early with no complicating factors and lots of spare cash!"
But I know what you are on about :thumbup:
Still, definitely inspired :dremel:
Ralph.
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I will try to give you a bit of inspiration when you call tomorrow Ralph, how to sweep out a workshop in one easy lesson.
That is what my instructor used to say if ever he caught anyone doing nothing. 'There is always something to do, even if it is only sweeping up'.
Now back onto the matter in hand, the flywheel.
I have a bit of a compulsion about flywheels. Usually they are the most noticeable item on an engine, and if they run out even a tiny amount on the rim and sides, they can spoil the look of an engine completely. So I will go to great lengths to achieve, if possible, a flywheel with no runout at all on the rim area. As far as I am concerned the spokes and hub, even though a little out don't detract from anything if the rim is spot on.
Unlike a bulky cast iron flywheel, where the rough casting adds character, my personal view with this one is that the more it is cleaned up, the better it will look. It has a very elegant shape, especially the tapered in rim sides and the eliptical cross section tapered spokes. Some might agree, lots won't. But to me a casting is just a means to an end, a finished correctly shaped component, if it needs every surface machining, then it gets it, if it doesn't, then the cast finish is left as is.
The casting for this flywheel, on first inspection looked fairly good, just loads of flash around the spokes to clean up. But on closer inpection, there was a fair amount of mismatch between the two halves as they were cast, as you can see on the rim mounted in the chuck.
So the first thing I did was to get it onto my RT and clean up the inner hub area, for somewhere for my chuck to hold onto with some semblance of precision.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT116.jpg)
I needed to use a smaller range of chucks for this job, so my lathe was converted over to a Myford nose, and because there were 8 spokes, I used my small 4 jaw self centring chuck.
Using the newly made nudger, the rim edge was brought to run true.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT117.jpg)
I soon had the outer rim, the rim face, hub and centre hole all finished at the same settings, so no matter what, this side of the wheel will look spot on. It was then flipped over and pushed backed with the machined rim edge right on the jaw faces. The second rim edge and hub was machined up. I now had a flywheel with the major edges running perfectly true.
After this stage, the flywheel was put back on the RT to have the inner rims that were machined before, gently trimmed to run perfect with the outer rim.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT118.jpg)
The flywheel again was mounted back onto the lathe chuck and the angle for the funny shaped sides found, 8°. Once that was done, those areas were cleaned up by using the topslide set over to do the cuts.
So this is the almost finished flywheel, just requiring a little bit of filework to blend the spokes into the rim and get the spokes straightened up down their tapers.
Not one single bit of wobble detected. :ddb: :ddb: :ddb:
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT119.jpg)
It is such a shame that most of it will be covered in paint.
So that is all the major pieces done except for a few clean up bits, I can now get onto the small easy to make stuff.
Bogs
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Beautifully thought through, and executed John! :clap:
Given me several ideas for the 'orribly mismatched, Robinson flywheel...... :thumbup:
David D
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Thanks Dave.
I always have a problem, if I haven't got a strategy plan to work to, I invarariably put off machining until I have. Sometimes it can be a few minutes, sometimes weeks. It might even be a bit of tooling needs making or purchasing that delays things, but invariably, when it comes to the time, I will be following a pre planned route.
I do occasionally 'wing it', but only when it is something that can be made again relatively easily if a mistake occurs. This component isn't one of those.
John
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That is a nice looking flywheel now John. I think it looks really nice in bronze, but always think it's strange they don't use cast iron for things like flywheels as it'd be more representative of an original. Must be easier to cast bronze? Lower temp?
Great work :thumbup:, I can see a rotary table would be useful for me but then I'd need the appropriate adaptors and tooling to go with it.
Nick
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Nick,
I don't know why but on smaller engines bronze seems to be a favourite, but I could see it getting very expensive on a larger engine if it was used.
I am now trying to do a lot more on my mill, as the lathe is now getting rather difficult for me sometimes, that is the main reason for the RT, that is the tool that resembles the lathe the closest. I reckon with a little work, I could have done the whole lot on there.
John
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Quite incredible, most people see their lathe as the cornerstone of their workshop but you are showing with that extra axis that so much can be done on the mill too, and it has a larger capacity.
:thumbup:
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I will try to give you a bit of inspiration when you call tomorrow Ralph, how to sweep out a workshop in one easy lesson.
That is what my instructor used to say if ever he caught anyone doing nothing. 'There is always something to do, even if it is only sweeping up'.
:lol: You should have :wack: me today John. I only just read this post! It was a very similar affair in the garages too.... Never get caught standing around! :whip:
The engine so far looks very good in person too. Pretty damn big too :thumbup: proper smooth machined/lapped surfaces :dremel:
I've sneak previewed the flywheel in it's next stage too :borg:
Cheers for today John, always good to "beat the gums" as you say :beer:
(Thanks to Mal too for the choccies :ddb: )
Ralph.
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Hi John, that engine is coming along very nicely, and I have seen good cause for having a self-centering four jaw for the first time, and will be keeping an eye out for one. I think the bronze is used because it casts so easily, and at lower temperatures, and iron is used when the amount of bronze gets prohibitively expensive. I personally like the offset that the use of both bronze and iron makes for looks, and often, for utility, as iron moves less with temperature while bronze is better in corrosive environments. I hope to see at least a glimmer of bronze when you have that flywheel painted up, it has really turned out nice, and the form fits very well with the whole of the engine. A very nice job on setting up the cylinder, head, a water hopper, and getting the port in proper place. It should be quite a runner when finished. Funny, I seem to remember my shop teacher having a very similar outlook on idle hands. All together, very nicely done, and getting close to running. :beer: cheers, Jack
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Jack,
Thanks for the comments, and I actually use my 4 jaw self centring more than the 3 jaw, I find they run slightly truer and give that extra bit of grip and versatility when needed.
The flywheel will actually be having the whole rim area showing with just the spokes, inner rim and hub painted. It has started to be blinged up with a few detail features, so until the first firing up, it won't be shown as it is put away for protection, while I am still doing rough work on the engine.
Talking about doing a bit of rough work, I have now just completed the main crank and valve operating cam.
The blanks were made up to the drawing dimensions, and using a few basic marking out tools, what needed to be trimmed off was drawn onto them. Nothing too special, near enough will be good enough except for fixed datum points, centre hole in relation to crank throw and operating angle of cam.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT120.jpg)
To cut the cam flanks, I just placed a parallel along the vice jaw top and eyeballed the drawn line to be in line with the top of the para.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT121.jpg)
It was then cut away until the cutter just touched on the central boss.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT122.jpg)
The same was then done with the other flank line. It was remeasured and found to be spot on the required 120 degs. seperation.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT123.jpg)
Next came the crank disc to have a bit of hacking done to it.
Because I will be swinging a fairly large cutter about, cutting to full depth of the flange, I put a washer on top of each jaw as spacers, to stop the cutter hitting my hardened chuck jaws.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT124.jpg)
With the part being tapped down onto the washers and being held in the jaws on the back boss, the RT was centred up on the crank spindle hole by putting a 6mm spotting drill in the quill and moving the RT about until the drill centred perfectly in the hole.
Next I moved the RT 1" to the left (crank throw dimension) and by turning the RT, I got the spot drill exactly over the centre line of the crank disc. The 5/32"(4mm) tapping hole was then drilled. Crank throw sorted.
The RT was then locked up so that it coudn't be rotated.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT125.jpg)
Next came cutting out the recesses using a 3/4" slot drill.
By using the X & Y traverses, the marked areas were cut out using shallow cuts until they split the marked lines.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT126.jpg)
The first one done, the second soon followed suit.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT127.jpg)
A little bit of filework in the bench vice had everything trimmed down to the lines, followed by a quickie clean up.
Except for drilling their grub screw holes, job done.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT128.jpg)
Now I can start on the operating rods, made from brass. Rather than following patterns and plans religiously, as long as the holes are in the right places, and nothing fouls, I should be able to use a little artistic licence.
Bogs
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Those parts came out great John :bow:
And thanks for the tip on those washers on the chuck jaws; that will certainly come in handy on many occasions.
Kind regards, Arnold
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Hi John
You sure are making cracking progress :clap: :clap: ,,,,,,,,,,,,,,, looks like the division master is getting a good work out too :dremel: well worth the time to build one :med:
Rob
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This is moving right along. I hadn't read the thread for a week or so, and enjoyed the past 4-5 pages a lot.
For those who have them (or can get them), the Jacobs rubberflex collets and chuck are also useful for holding thin-walled tubes in the lathe.
I noticed you mentioned using the centering device in the lathe. I recently bought one and am wondering what the technique you use in the lathe. I assume that the tailstock needs a rotating chuck or the like for centering a bore in a 4-jaw (or am I missing something obvious?)
-
Still watching, have enjoyed this and a few other projects whilst on my break from the workshop - great work, pics and write up.
Nick
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Arnold, I'm glad you can still glean a few tips from my ramblings. It is simple ones like that which can overcome major problems. The other way around the problem I had would have been to make a dedicated holding mandrel to get clearance for the cutter. Three little washers was the easiest route, so why not take it?
Some people could easily get carried away when faced with a problem like that. I know, I have done it.
Actually Rob, the reason I put a winding handle on the stepper was for occasions such as this. I didn't require the DivisionMaster this time, as it only needed to be turned a couple of degrees, all other movements were done with the mill itself.
Kvom,
If you mount the coax indicator in an accurate running chuck, and have it touching on a full solid centre held in the tailstock, the tailstock (as long as it doesn't have a droop snoot) can be realigned perfectly side to side.
If you mount it into a normal chuck in the tailstock, and indicating on a part in the rotating lathe chuck, it will work exactly the same as having the coax spinning. So you can use the centre finder tip into a punch mark, or inside or outside indication just by rotating the four jaw. It works in exactly the same way as a normal DTI being held on a magnetic stand.
Still getting there Nick.
John
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Arnold, I'm glad you can still glean a few tips from my ramblings. It is simple ones like that which can overcome major problems. The other way around the problem I had would have been to make a dedicated holding mandrel to get clearance for the cutter. Three little washers was the easiest route, so why not take it?
Some people could easily get carried away when faced with a problem like that. I know, I have done it.
Actually Rob, the reason I put a winding handle on the stepper was for occasions such as this. I didn't require the DivisionMaster this time, as it only needed to be turned a couple of degrees, all other movements were done with the mill itself.
Kvom,
If you mount the coax indicator in an accurate running chuck, and have it touching on a full solid centre held in the tailstock, the tailstock (as long as it doesn't have a droop snoot) can be realigned perfectly side to side.
If you mount it into a normal chuck in the tailstock, and indicating on a part in the rotating lathe chuck, it will work exactly the same as having the coax spinning. So you can use the centre finder tip into a punch mark, or inside or outside indication just by rotating the four jaw. It works in exactly the same way as a normal DTI being held on a magnetic stand.
Still getting there Nick.
John
John
Having just got a coaxial indicator myself ( Amadeal do them for £48 inc vat ) , I am confused with your comment on using it in a normal tailstock chuck indicating on the part in the main chuck , my indicator only moves in one plane ( no problem if that is rotating ) but would your method not put side strain on the device. I can see how it could be used with a rotting tailstock chuck and the work stationary as it is in a mill
or am I missing something as usual :doh:
Stuart
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Stuart,
I don't see how it could put side strain on, purely because as the probe is moved, the way the coax unit is built, it turns that sideways movement of the probe into the linear movement of the coax body moving up and down it's shaft. Hold the coax by it's main spindle and press on the probe to see what I mean.
So it makes no difference whether the part is rotating and giving an offset reading or the part stationary coax spindle rotating.
But of course, if you are using the coax stationary, you have to do all you adjusting in line with an imaginary line from the probe tip to the centre of the coax unit.
John
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John thanks for the reply
"If you mount it into a normal chuck in the tailstock, and indicating on a part in the rotating lathe chuck, it will work exactly the same as having the coax spinning" quote from your first post
surly in this case the coax is stationary ? it may be the way mine is but the pivot will only allow movement in one plane , as it pulls down on the levers on to the body and causes the innards to rise and fall thus operating the dial
Stuart
PS
John I do not want to take your topic off track
-
That is what I am trying to get across Stuart, if the part in the lathe chuck is off centre, the spring loaded stylus (kept in contact with the inner or outer wall of the part by the spring loading of the coax unit itself) will follow that eccentricity and give you your reading, as the main body slides up and down it's stationary spindle.
A DTI would most probably do things a lot simpler, but there is nothing stopping you using the coax as I have said.
After this, it means video, which I don't want to get wrapped up into at this time.
John
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Pennys dropped John :doh:
It will work with the stylus on the outer or inner of the part fine that I can see, but use the spring loaded centre probe in a centre pop mark and things would be different as the tip would describe a circle
Any way I will not clog up this post with further waffle , If my skills allow I will try to make a vid in a new thread
Regards Stuart
PS keep up the good work and valuable postings , I to am mobility challenged and need a wheel chair or crutches for short distances
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Hi John, I expect the flywheel will look right nice with the rest of the engine, according to your description, and your description of using the centering indicator in the tailstock chuck sounds easier than my typical use of a dti stuck on my cross slide, to center something in the four jaw or on a face plate. That will be stored for future use. :beer: cheers, Jack
-
Crank looks good, John. I like the washers on the chuck, too. Arnold and I both got a freebie. : )
-
Thanks gents.
Soon after starting this build, I stated that I would be looking to put my own stamp on this engine, just to make it look a little different from the ones that have gone before that have been built to what is shown on the plans.
After getting the big bits out of the way, where very little could be changed, I am now into 'almost anything goes' territory, and I will be looking to make a few changes.
Have a look at this con rod, exciting ain't it, not.
I have laid out the metal and bearing just to show what the finished item will look like, I am sure a little redesign will help some.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT129.jpg)
I won't be able to do anything with the rod that goes into the cylinder, as it will be tight as is.
But the bit on the outside should be able to be given a makeover, so I measured up to see what I had to play with.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT130.jpg)
The plans are nowhere near to scale, so it might look a little funny when I place parts against it. Also at this time I am totally disregarding balancing of parts for changes I will make, if it needs doing, I will do it all at the end.
I have decided to go with a two part build, the original bits that goes into the cylinder will basically stay the same, the bits outside are now mine.
I will make the two parts, then fix them together, then drill the critical dimension for giving the correct length.
I made a rough pencil sketch on the plans of what I want it to look like.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT131.jpg)
Again, just using a few marking out tools, I transferred my idea onto the metal.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT132.jpg)
No special machining needed, just the para on top of the jaws trick to line things up, then cut to split the line.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT133.jpg)
That was done in a matter of minutes.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT134.jpg)
The curvy bits at the back got the same treatment, cut until it reaches the line.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT135.jpg)
As you can see, just a few easy cuts and the complicated looking part is taking shape.
I also drilled a few holes to remove metal and allow access for my hand files. The part was then put into the vice and rough shaped. This is too small a job to break out the die filer, things were easily done by hand.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT136.jpg)
The two rough parts were then joined together. The ali blocks under and the weights on top were my attempt to keep the two parts flat and in line with each other. It worked.
The joint was silver soldered using my method of fluxing the joints, placing a pallion of silver solder sheet on top of the joint and heating from underneath.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT137.jpg)
The solder flowed right thru the joint and gave a permanent strong joint.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT138.jpg)
After a good clean up, the large hole was picked up using a transfer punch in the drill chuck. Once I had that zero point, I just fed along and drilled the other critical hole.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT139.jpg)
I milled the conrod to thickness in the parts required then set about putting in the half round flutes.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT140.jpg)
A little more shaping up and it is ready to be put away for final shaping and polishing at a later date.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT141.jpg)
There are all sorts of rods and linkages now that will get the same sort of treatment. No plain flat bars for me any more.
Bogs
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Really like the conrod John, the one on the drawing looks exactly like my Jan Ridders one!! :lol: Maybe it's time I started exercising artistic license instead of functional license - up until now I tend to make things easier to make!
Just as a slight aside, there's a Beam engine near us at the old water works which has running days from time to time. Got into a bit of a discussion with one of the volunteers that helps run it about how fancy it all was. He said that on parts of the drawing, the critical dimensions were shown but there were supplimentary notes "To be made eyeable" - I believe this is what you are doing. Looks great.
Nick
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Looking good John
:thumbup:
Never would have thought of a butt joint.
hmmmm that gives me an idea.
Stew
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It's so very nice. :clap:
-
Thanks gents,
DKM,
I love just making things like this, I have been doing it all my life and it gets me back to basics when machinery was just a distant hope. I can do a bit of filing when I feel up to it, and it gives me great pleasure just hacking a lump up by hand. A liitle later, when I get to building more complicated things and shapes, I will start to use my die filer
Nick,
At one time everything was done by eye and feel, if it looks right, then you can bet your bottom dollar it won't be far off.
The Victorians put embellishments onto their machinery just because they could, in fact looking at some of their work, I think the add ons took longer to make than the actual engines. Everything had to be 'just so'. Cutting to a line is plenty accurate enough for things like this.
Stew,
Doing it that way can save a lot on materials, one big expensive piece, or a couple of offcuts, that once made up, turn into something that would be difficult to machine and make if made out of one piece.
John
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Very nicely done, and without any over doing the bling, just making it look like a part, and not a bar of scrap, John. I dare say the rod is more functionally true as well, although with these small flame eaters, power isn't exactly a problem. I milled out my last couple of cams exactly the same way, although without figures for timing, but as you said, looking across the para works fine, and is plenty accurate, and gets the job done right now. All in all, everything is coming together quite nicely, and should be a runner very soon. Makes me wish it were my build :lol: :poke: great job, John, :beer: cheers, Jack
-
A few more rods to do. I won't be showing them all as it is a waste of good space, but I will be showing a few things I did to get them made.
These are the rods that need making, and again a little bland to look at.
There is one at 1/8" thick, that is the operating rod from the cam, two from the cross shaft at 1/16" thick and two going up to the graphite block, again 1/16".
The two offs are actually handed pairs, but can be made up as a pair, then the handing put on afterwards. So to make sure they match, I will join them together, machine and shape them as one, then split them apart.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT142.jpg)
The first job needed is to solder the two 1/16" plates together.
This is my soft solder joining kit. The small G clamps are not used unless the two plates start to wander apart.
The first job is to coat each face with flux, then by hitting the soft plumbers solder between a clean hammer and a hard place it is got to about 0.005" thick. Using scissors, little pallion strips are cut off the flattened solder end and placed along one of the fluxed faces.
The other plate is placed on top, flux face to the solder and the whole lot gently heated until the solder flowed and then allowed to cool down naturally, do not quench, as it will suck water into the joint and be liable to fail, that goes for all soft soldering jobs.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT143.jpg)
Soft solder is fairly fluid, even when set, so if the plates are slightly out of line, I put them into the vice edge on and realign them, followed by flat faces and then a good squeeze. These were fairly close, so they aligned really nicely. If they are way out, they need to be reheated and got more into line, that is when I would use the G clamps, while the solder is still hot and liquid. I find it stays that way for quite a while, as the main metal cools down.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT144.jpg)
A working measurement was required to make the thicker plate, so I needed to get it so that I could measure between two centres at different heights. With a little bit of thinking, the figure was obtained. The edge of the small mag stand was set on centre of the lower one, the small square onto the upper one, and the ruler taking the measurement. 1/32" is plenty close enough for this piece.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT145.jpg)
The bar that had been soldered up was cut into the two required lengths, then by drilling on the mill I got all centres thru with a 1/16" drill.
After bluing up, my rough sketches were laid out onto the plates. All the holes were then opened up to 1/8".
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT146.jpg)
The next job was to make up a pair of filing buttons. These were made from a piece of 1/4" silver steel (drill rod), drilled down the centre with a 1/8" drill then parted off at about 1/8" thick. Then they were heated up to orangy red for about 30 seconds and then dropped into a tub of cold water. They came out glass hard, just what is needed, and no need to clean them up. A short 1/8" spindle was made up out of a piece of unhardened silver steel.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT147.jpg)
This is how they work. One either side of the bit to be filed to shape and then the spindle is rested on top of the vice jaws as the vice is tightened up, trapping the part between the two buttons.
You then file downwards until you can file no more, the buttons are so hard, if you carry on, your file will soon be buggered. Just file around the buttons until the ends become very nicely radiused, taking on the shape of the buttons.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT148.jpg)
It only took a couple of minutes to get these done, then it was onto the mill to split the drawn lines, as shown in previous posts, then a little hand filing to blend things together.
If you notice, there is only one filing button here, the other shattered when I tightened up the vice on one of the other plates, so I had to rely on my ability to keep the file level while going down to size.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT149.jpg)
The extra holes in the centres of the rods will actually have small steel decorative finials fitted (6 off overall), just to finish them off.
Pivots, torque rod and springs next.
Bogs
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Those rods look very "eyeable", with the nice figured curly cues fancied into them, far better than rectangular bar stock with holes. Very nice work there. Looking forward to watching the soon to come video, I hope. very nice indeed. :bugeye: Jack
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This is unfare, it seams so easey when you are doing somthing... :(
-
Jack,
This isn't completely finished yet, that all happens when I prepare them for polishing, but they look a lot smaller in real life than they do on a drawing.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/DSCF5723.jpg)
Saw,
If I can do it, anyone with a little patience and a few tools can as well. A lot of problems with making things is with the person thinking he can't do it, not the actually doing of it.
Have a look at my signature line.
Bogs
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Holding it like that puts it all in proper perspective, John. I still stand on the statement that's fine work, and artfully done. I think the little extras really make the engine interesting, and "eyeable". :beer: Jack
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Nice exposition of techniques as always.
I was wondering about the tight spiral on the endmill you showed milling the conrod. I have a couple of endmills with such spirals and wonder why they're that way.
-
Kvom,
A great many of my solid tungsten ones are like that one, six fluted with a tightish spiral, and used mainly in the aerospace industry. I think they are made that way because they are designed for giving a superior finish on harder materials.
When I carry out face milling with them, even on something like gauge plate, the finish comes out like a mirror, even with a heavy cut.
Bogs
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Yeah, those end mills caught my attention as well. Those are called high helix or high helix angle end mills. They are mostly described as useful for softer materials like aluminum and for providing a nicer finish, although some reports I've read say they don't give as nice a finish on steel as lower helix angle flutes. Never saw a six fluted high helix end mill before.
Chuck
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Always very inspiring work Mr Standard! :beer:
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Thanks for the info on the cutters. As you can most probably guess, with some at around 150 squid (over 200 bucks) each, I don't pay for them, kind donations from the scrap bin, 'nuff said.
BTW, the reason I used that cutter rather than a standard HSS one was because all the ones of that type that I possess have a very nice corner radius, the one I used was 0.5mm rad.
Today I decided a few things needed to be finished off before going any further.
Using my horizontal belt sander, the top and front previously machined faces of the water jacket and the other rough fettled faces were given a good going over. The only one left untouched was the base which I had machined up. I will also be giving it a dose of heavyweight grit blast, and if the surface comes out well enough, I just might not paint it.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT150.jpg)
The jacket also needed to have the stainless studs fitting. The build calls for hex head bolts, but I always think that covers such as this always look better with studs and nuts.
So it was just a matter of putting a nut and washer on the threaded rod, screwing it into the hole and tightening up the nut, followed by a quickie chop off with a reinforced cutting disc.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT151.jpg)
Soon done.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT152.jpg)
The first of many disassemblies. This time to Loctite the studs into their holes.
Once set, the whole lot was reassembled, with just one washer under the nut. Normally, I would fit two, chop off the exposed stud, remove one washer and they would all be nicely the same length protruding from the nut.
This time on final assembly there will be no washers fitted because they extend out over the edge of the cover, as the bolt holes are very close to the edge because of the graphite block needs some space in the middle to move about. The nuts fit perfectly to the edge.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT153.jpg)
The uneven lengths of studding were soon machined down to just above the nuts.
I wish someone would come up with a tool that does backwards countersinking. Place on top of the cut stud, give it a turn, and a nice chamfer is put on the end.
I must think about making one.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT154.jpg)
Finished off nicely.
In fact it will need another strip down to not only finish off the jacket, but also seal things up. But as it is, it should be fine for trial runs.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT155.jpg)
Another thing I have been pondering over is running this shaft in just drilled holes in the casting, a thing I personally don't like, so I took the decision to ball race it.
I had bought some nice 7mm diameter low profile ball races a while ago from China, and because there shouldn't be much heat in the area, I decided to leave the rubber seals in. This serves me two purposes, the action will be much smoother with less friction, and I won't have to make and fit the required oil cups.
They will be hidden from view on final assembly.
If you notice, the holes in the upstands aren't central, they were drilled to dimensions required on the plans.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT156.jpg)
Because I had previously machined up datum edges on the base casting, it was dead easy, using the DRO, to pick up the holes again.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT157.jpg)
First off, the hole was gone thru with a 5mm milling cutter, just so the original holes didn't interfere with the running of the shaft.
It was then followed down with a 7mm cutter to a depth of 2.5mm, diameter and thickness of the bearings. This was done to both upstands.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT158.jpg)
Ballraced shaft done, and I am now a lot more happy.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT159.jpg)
The next job concerned the camshaft follower arm, it required a 1/8" offset joggle putting into it.
By heating up just the part that was affected (the black bit), that area was annealed, to make it softer for bending. Just heat up to an orangey red, and either leave to air cool, or as I prefer, because it is quicker, quench in cold water. Both ways work just as well as each other.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT160.jpg)
A little bit difficult to see, this is how I set it up in the vice. A 1/8" parallel either side, at the position of the start and end of the joggle. The vice was then tightened up and left for a few minutes.
Once taken out, it only required a tiny amount of hand tweaking to get it perfectly in line, and by the time I had finished, it had work hardened almost back to normal. It will carry on age hardening over time.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT161.jpg)
You will also notice that I have cut a small recess in the crank disc, this will be filled with engine colour paint to give a nice contrast.
It is now starting to look like a finished engine.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT162.jpg)
Methinks a little more polishing and loads of fixings to be made.
Bogs
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It seems I learn something or two every time I visit the site. I like how you put the offset using the parallels and the vice. A handy new trick. Love your work bogstandard. Looking very good.
-
Tanks for chearing Bogs. It's always a plesure to read your'e work-storys, and to see how you succesfully can make sucht a beutifull engine. I'll hope that day's will come when I can make something close to your'e building. :bow: :bow: :bow:
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Thanks for the nice comments gents, and Benni, there are very few tricks involved at all, a lot of common sense, taking your time over things and making one good part at a time. You will do it in the end if you keep trying.
My machinery does help, but that, in the distant past, never stopped me from making engines just as good as this one. In fact, a hacksaw and a file can do almost everything a mill can, and that used to be my early way when I couldn't afford one, shame I can't do it that way nowadays.
Bogs
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I wish someone would come up with a tool that does backwards countersinking. Place on top of the cut stud, give it a turn, and a nice chamfer is put on the end. I must think about making one.
They certainly make them for the woodsmiths, used for putting ends on dowels.
-
Thanks for the endmill explanation Mr. DKM.
And nice work as always Mr. Bogs.
-
I wish someone would come up with a tool that does backwards countersinking.
Something like this (http://i758.photobucket.com/albums/xx229/dougmeller/stayheadformingtool.jpg) perhaps? This is shaped to round over the ends of boiler stays but I have seen similar for studs.
Starting to look like an engine now, keep it up.
Jason
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That is it Jason, but with say a 90 deg angle instead of being rounded.
Many thanks for the picture, that shows me exactly what needs doing.
A bit difficult at this time, but still attempting to get two hours a day in.
John
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Very nice John,
Nearly there now.
I will be trying to get back in the shop / garage tonight after my month and a bit sabatical, starting with a good old clean up!
Nick
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Very nicely done in all regards, John, like so many others, the ways and means you use are quite often new ideas for doing things, and will be faithfully carried on. As an aside, I've noticed on some of my cheaper, read "chinese" center cutting end mills, they get rather a lot of angle on the end cutting flutes, and if centered on a short stud or such, could be used to clean up the end. I hadn't thought of it myself, but I believe it would be rather easy to take a stone and increase that angle, and add some curve to it, making it cut much like you describe. I hate the look and blood of unfinished studs and cut off screws, and usually bevel them with a belt sander, or if they've been cut off in situ, as yours, carefully with a small file, although that seldom gives as good an end result. I want my stud end square, the threads ended with about a thirty degree angle, and the "tail end" of that last thread chased with a file right down to the smooth flat end. Easy to do with rod and a belt sander, a bit of work with file and not leaving scars on finished surroundings. All in all, a very fine looking engine, and that touch with the crank counterweight is a "crowning touch". :beer: You do very fine and artful work, Jack
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Jack,
As you know, I have very limited time each day to do this work. Well I went into the shop this morning to finish off the linkages.
I found I had joggled the cam rod the wrong way. Normally it would not have been a problem, but because of my shaping of the rod, it ended upside down. So my couple of hours today have been wasted putting it right.
To me, making mistakes is a good sign. It saves you getting too big headed when everything goes perfectly, it proves you are just human.
John
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John, sorry to hear about the rod - sods law as everything was going swimmingly, you're right though it keeps you on your toes I guess and it shows that these things don't only happen to relatively inexperienced chaps like me! Glad you sorted it.
Out of interest, how often do you clean the workshop? After every nights work? I gave my machines a decent clean and oiled the slideways etc tonight. It hadn't been done since I started back up on poppin - it was a mess and not nice to work in. I know my grandad was a bit of a stickler for cleanliness in the workshop, he would not have been impressed at all. I thought I'd do it after each project but it was too long. Apparently one of the old guys that sadly passed away from our club always had his workshop so that you could virtually eat off the surfaces - sounds great, but is it really necessary?
Nick
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Nick,
No one is perfect, so you should always show or tell, if not too embarrasing, your mistakes as well. Like you said, it shows that people with lots of experience also cock things up as well.
But, if it can be fixed, like mine was, it wasn't a cock up, it was just going thru a modification stage.
Workshop cleaning sadly is a thing I can't do myself. But my machines usually get a brush down onto the drip tray when I change chucks or change job in the vice. Mass machine curly swarf is cleaned away into the bin straight away. My machines get over oiled, at least once a session, maybe twice, especially on the mill as I have one shot lube. It might make the machines look filthy, but at least they are staying accurate and not wearing away too quickly. Oil is cheaper than new machinery.
Normally my wife and daughter get in the shop when I ask them and give it a good clean out, after I have emptied the drip trays onto the floor. I don't mind them putting the hoover pipe onto the machines, but I don't want them in there with their hands.
All my machine cutting tools go back as soon as I have finished with them, but I am like I think most people are, my worktop gets covered in hand tools, and get them put away en mass when I can't find a bit of space to work on.
John
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All my machine cutting tools go back as soon as I have finished with them, but I am like I think most people are, my worktop gets covered in hand tools, and get them put away en mass when I can't find a bit of space to work on.
x2
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Thanks John, good to know it's not just me that finds myself working in a mess. I went to the trouble of getting the proper miller slideway oil but have hardly used any so I'll have to get into the habbit. My lathe has lots of grease nipples everywhere so I put it in the gun that was under the lathe cabinet - think it's actually a grease gun though so tends to leak a bit! On the mill I just have to use a silly plastic bottle that came with it. Should maybe invest in a proper oil can!
That's good getting them to help out but as you said, it's easy to pick up splinters, I got a couple last night but think I managed to scrub them out as can't feel anything this morning. I'll have to clear the curly swarf out straight away in future as that quickly blocks the hoover.
I need to take time to make some decent storage for tools etc like yours, it makes using the workshop much nicer.
Nick
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All my machine cutting tools go back as soon as I have finished with them, but I am like I think most people are, my worktop gets covered in hand tools, and get them put away en mass when I can't find a bit of space to work on.
Actually, I have become adept at filling my available work surfaces with tools and swarf, then pushing the combined mess to the rear of the worktop to leave a small space in which to place yet more tools and swarf!!!
Tim
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All my machine cutting tools go back as soon as I have finished with them, but I am like I think most people are, my worktop gets covered in hand tools, and get them put away en mass when I can't find a bit of space to work on.
x2
x3
Stuart
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Well, with a post like that, I have to chime in :lol: like you John, I have limits because of my M.S., I do what I can, but if I do an extra hour's work today, I won't be able to work tomorrow, so I stop when it's time, unless it's an emergency, and then I just go ahead, knowing I will pay the price, without any doubt. At the beginning of the M.S., I cleaned every machine after using it, at the end of each day. Not eat off of clean, but ready to put a piece in and work clean, and periodic "field days", bulkhead to bulkhead, deck to overhead, clean enough for an inspection. I am now satisfied if I can work on the machines, if I can get the full swarf buckets out, and I can find all my tools. I have way too much space, in a forty by sixty foot building, but I sort my collected "junk", separating out scrap metal and all recycleables, because they mean money, and every couple of years make a major haul to the dump site. I do everything in my power to prevent any damage done to my machines by dirt, swarf, grit, but if it doesn't cause problems, it's not that important. My wife has M.S. also, my daughter is going blind from an eye disease and my son lives with us to help keep the sixty odd acres cared for, and I'll be fine with someone having to clean the mess when I'm gone. They might find something really valuable given my penchant for odds and ends which end up being unique and valuable sometimes. I will be posting another engine soon, but yesterday I was drilling and tapping holes for the head in a cylinder, and power tapped with the wrong tap and broke it off. After welding on it, and doing everything I could to remove it, I found I was stuck with it. It was a four bolt pattern, so I put it back in the mill and lined it up and drilled and tapped a six hole pattern which fit around the three holes and one broken off tap, and will be covered by the head when it's done. I keep learning the same lessons again and again, maybe I should reconsider my position on certain subjects? :bugeye: cheers, Jack
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It gets to us all sometime Jack, no one is spared.
But anyway, lets get this post back on track.
Only one picture tonight, very similar to the last one I posted. But in fact there has been a fair amount of progress (for me at least).
Mainly things you don't consider take much time, but actually do. Making up bearing spacers, silver soldering a few bits 'n bobs together and drilling and tapping all the grub screw holes, plus working out how to get around bad practices on the original build. There is no way will I Loctite a couple of bearings to a shaft, then Loctite the bearings and shaft down into a hole, I want it to come apart without too much trouble whenever I want.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT163.jpg)
It is all mainly tiny steelwork from now on, special bolts, bifurcated rivets, little bling buttons, springs etc.
I can't get too far ahead, I am waiting for some bits that I thought I wouldn't need for the burner, plus I also have to get out of the house to buy some copper pipe fittings, again for the burner.
Bogs
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:nrocks: Hi John I just wanted to say it's coming along quite nicely, and I'm looking forward to seeing that burner go together. Jack
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:clap:Thanks for the education John. I missed the start of this build, so have read it thru in a few evenings. As with all your projects shown here it is beautiful work, beautifully presented. A question or two, in reply 137, what is the device attached to the scale, and could you show an altogether picture of it? I don't think I've seen one before. Thank You.
Jim
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Jim,
The only thing I can notice that you are on about are my very small spring dividers (donated to me last year by another member, and very nice they are too), and if you look at post 144, 5th piccy down, it shows them in full view. Next to the RDG special freebie 6" rule, they give you an extra inch just in case you lose one at sometime.
Sorry about that, as I usually try to show the major hand tools I used in each shot, but sometimes they would overwhealm what I was trying to show, so you only get a partial shot of them.
I'm glad you are enjoying the build.
John
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The tool I was asking about is in the shot where you were measuring to decide what to do with the rod. It's a rule or maybe a depth gage with a sliding member ending in a sort of hooked pointer which is indicating about 1 and 41/64". I'm just curious, I don't recall ever seeing one like that, and wondered what it was.
Your swing up threading tool is near the top of my to do list when I get a mill. That's a first class design.
-
Jim,
My curiosity got the best of me and I went back to look at what you are describing. Are you talking about the second pic in reply #137? If so I believe what you think is a depth gage is actually part of the engine. Just a guess.
Trying to help out Bog's. Hope you don't mind.
Bernd
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Jim,
Bernd is correct, the bit behind the rule is actually the crank disc, and yes, the hole in it is supposed to be that close to the edge.
I was rough measuring from near the end of the cylinder to the centre of that hole.
John
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Well egg on my face. It's easy to see now that I know what I'm seeing. Strange how a wrong first impression can be so persistant.
Jim
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No problems Jim, it gets to us all at sometime or another :lol:
Better to ask than not understand.
John
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Jim,
Didn't you know John is a master illusionist? :lol: :lol:
Bernd
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Yep, it sure got me, I looked at it several times and saw the same thing each time. I first saw an ad for Fram filters in the Progressive Farmer magazine when I was a teenager. For years I thought it was Farm filters until I heard someone ask for a Fram filter at a parts counter. Good thing I never needed to ask for one or I would have embarrassed myself.
Jim
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It looks like I have abandoned this post, but far from it.
I have actually been making custom screws and other little bling bits, and if anyone has ever done them before, they are very time consuming. One little screw can take well over an hour or so.
I got to use the ER32 collet adaptor that I made a while ago today, and it was great.
I was doing multiple very small parts, and it held them perfectly concentric and they all turned out exactly the same.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT164.jpg)
This is what I have been making, screws, bifurcated rivets and decorative studs, all to a common theme, a six pointed star surrounding a central circle. Very easy to do but also effective. They are also very easy to tighten up with a pair of round nosed pliers.
I also made the piston to con rod joint, that once assembled inside the engine will never be seen.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT165.jpg)
This shows the context that they will be used in, one holding a bearing in place, another holding con rod to crank disk, bifurcated rivets for the curly bits on the end of the arms and decorative buttons at the centre of each flame valve operating arm and cam follower.
You have most probably noticed, I have tried the paint out on the crank disk, and I am not really sure about it. It is a satin finish metallic, which I have never used before and it looks sort of strange compared to my normal hi gloss efforts. I think I will give it a go and see what it looks like when a larger area is done.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT166.jpg)
I actually had the engine rough assembled tonight, just to check for fits and friction. With no oil anywhere, when the flywheel was spun gently, it gave a least a dozen nice smooth revolutions, so I don't think friction is going to be a problem.
There are still a few bits to make, mainly the main spindle, flame valve assembly, a leaf spring for the camshaft follower and power take off pulley. Plus of course the burner, the gas parts have arrived but I have yet to go out and get the plumbing fittings for it.
I am hoping to get the basic engine running very soon, then stripped down for painting and polishing.
Bogs
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John,
That is a very neat idea. :bugeye:
It sure will give your engine a unique look with those screws. I like it very much. :thumbup:
Your ER32 tool setup has given me an idea. I wonder if a setup like that could be done with a C5 collet? (sorry :offtopic: I know)
Bernd
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I think Bernd understated it just a tad bit, those bits are stunning and really show off the levers. I echo Bernd's question and idea about a five C version of such an attachment. I hope your journey for the plumbing parts goes well, I'm itching to see this engine run. cheers, Jack
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Comming along well John, though you could have saved yourself an hour or two :D
(http://www.acument.com/northamerica/images/img_torxpluselphead.jpg)
Though They are not easy to come by in small sizes and quantities.
I take it the rivits are only drilled a little way in so that the shank does not expand within the rod holes and lock everything up? Just enough to retain the pin.
J
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John (bogs)
How are you using the bifurcated rivets in a model application my take on that type of rivet is that they are used to hold leather or such . correct me if i am wrong but I remember them as rivet split up the shaft leaving two legs , that you can open out and fold over
from OSX dictionary
bifurcate verb |ˈbīfərˌkāt |
divide into two branches or forks:
adjective |bīˈfərkāt, ˈbīfərkit |
forked; branched:
Stuart
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I have tried those before Jason, and they don't quite look right, just like any other mass produced fittings. Plus these are shouldered bolts and plain shanks, not usually available, so I make them myself.
I used the reshaped heads a fair amount when I took Elmer's basic mine engine up a level or two.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/minefin1.jpg)
Both square and star headed were used to cover up bearings that weren't on the original build.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/Crankshaftfinished.jpg)
Yep, the bifurcated rivets are drilled to exact depth for just gripping onto the backing washer and not the other two plate parts. They have to swivel against each other as the angle of operation changes.
Bernd & Jack,
In all honesty, I think a 5C fitting would just be too high to be plonked on top of an RT, especially as you would have to have some sort of closer for them.
I have a large collection of 5C collets, but I think whatever chucks and fittings I have now for the RT and dividing head is perfectly adequate for what I want to do.
But I do suppose you could use something like this.
http://www.chronos.ltd.uk/acatalog/5C_Collet_Fixture_for_Milling_Machine_Bridgeport_etc.html
Stuart,
You are quite correct in your assumption of it being a two legged rivet, maybe I should have called it a semi tube rivet.
I was just using a term we used in the forces when working on aircraft, where the two legged versions would never be allowed, except maybe by some of the fabric trades, but even then, I would have expected them to use the same as I used purely for safety's sake.
They make disassembly very easy, just drill down to the bottom of the hole with a larger drill and the whole lot comes apart.
C-o-C at the bottom to explain use.
John
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Thanks John for the explanation and CoC
More like a manual pop rivet with a tapered pin to expand the part outside the joint
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That's OK Stuart, sorry for the confusion, just me using my old terminologies again rather than the correct ones.
John
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Once again, good progress John.
And thank you for the explanation on the rivets; I was also wondering about those.
Would it be correct to say that one can adjust the amount of play between the pivoting parts of the riveted joint by just punching it a bit more ?
I've not seen rivets used a lot in model builds of late, and I'm wondering why, as it seems a good method to use for many things...
Kind regards, Arnold
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Normally Arnold, you use a rounding over type of punch to make it look slightly like a dome head rivet, but a taper punch is plenty good enough for what I am doing, in fact I will be using a 90 degree centre punch end so the swelling is more towards the surface, so leaving the parts turnable loose rather than clinching them together.
The depth of hole plays an important role, too deep and it swells inside the rotating parts and locks them up, and yes, the easy way is to gently punch until you get the correct side float (not sloppy) and still have nice fairly free rotation.
If you want to get very technical and work it out with a calculator, there are charts about to give you starting points. But really it isn't necessary, I just drill down to depth until the drill tip reaches a point the same thickness as the parts being joined, and put a supporting washer on the opposite side of the head. I leave about 1/16" protruding from the washer.
http://www.doidge.com/english/semitub.html
John
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Tonight's little exercise turned out to be a bit of a dirty job.
One of the most important parts on the engine, the flame valve.
This is what it is made out of, a lump of graphite that has been rough sawn on all six sides, with not one side flat, straight or square.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT167.jpg)
When working with graphite, the dust can get everywhere. You can spray with fine mist of water, but the dust is even worse to clean up.
Not really recommended, I taped paper towel down to the vice and table to attempt to stop it going everywhere, and I kept the air blower well away from the machine. NEVER use anything other than easily torn paper like this, cloths and rags are a definite no-no.
I had to go thru the whole routine of getting the part all flat and square, and I used a razor sharp flycutter to do it. The dust just stayed in the local area, and was wiped away very gently from the parallel's surfaces at the change of face.
I used the flycutter because it gives a highly smooth and flat surface (as long as the machine is in tram), and will save me having to lap it flat later.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT168.jpg)
Once it was to size, by gently pecking away with the drill running a lot faster than normal, 1500 rpm, I got the drill thru the part very accurately.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT169.jpg)
Using a 90 degree countersink, the three bevel edges were added.
Everything while handling this material is done very softly, finger pressure to set down onto parallels, just using the weight of the vice handle to tighten the vice up, and of course slow steady cuts. You can easily shatter edges or even break it in half by being even a little heavy handed with it.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT170.jpg)
Spot on size and not a chip in sight, and the valve face was as flat as though I had surface ground it.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT171.jpg)
This is the face it will operate against, opening and closing the port so that flame gets sucked in at the right time.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT172.jpg)
This is the state of my hands just by handling the stuff, and I haven't even touched the dust hardly, so you can imagine what state the front of my t-shirt is in. That is one I will have to sneak into the washing basket.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT173.jpg)
I am still a little undecided about the springs supplied for holding this valve onto the face, they look decidedly heavy, so I will try them, but if they are too much, a redesign will be called for.
Bogs
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John,
Would a vacuum cleaner nozzel placed near the cut to suck away the dust have worked?
I wouldn't through that shirt in with the other laundry. Might get that stuff all over the other laundry or were just telling porkies? :lol:
Bernd
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Nice job on the valve, John. I liked the way the fasteners came out, too. They look like they were crafted, rather
than just cookie cutter punch outs. I think they will look good in place.
Dean
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Bernd, would you like a vacuum droning away in your ear for about hour and a half while you are trying to concentrate on something. No thanks, and besides, once I wrapped up the paper towelling, it was basically all gone.
No joking about the t-shirt, but over here we have things like washing machines and powder to get things clean, we gave up pounding laundry on rocks at the side of the stream a few centuries ago.
John
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All looks brilliant John. Don't think there's any need for great tension in the springs either. Just enough to keep it flat against the port face.
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You are quite correct Nick, the springs are only there to keep the block in position, the vacuum produced by the engine will keep the block sealed against the face.
This is the quandry, too much spring pressure and there will be too much friction produced and the block will wear away in no time. The springs are a rather heavyweight about 3" long, maybe a bit more, and 1/4" diameter, but I do have an elegant looking redesign if these are just too strong in the beginning.
This engine will of course run with all these supplied bits in place, without any mods being done, but how long would it last?.
I always look for improvements, not for the sake of it, but to produce a more efficient design by well known methods. Most engines will run quite merrily without all the mods, ballraces et al, but when you do fit them, they make a very significant improvement not only in running quality, but to engine longevity.
John
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No joking about the t-shirt, but over here we have things like washing machines and powder to get things clean, we gave up pounding laundry on rocks at the side of the stream a few centuries ago.
John
Over hear we just throw them away. Why waste money on a washing machine and detergent. :scratch:
Bernd
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I agree, I think it will be unnecessary friction wearing the block a lot faster, they sound quite strong.
Your mods will no doubt make significant improvements. I guess the valve is quite a good design feature as the little bits of graphite from the block will be sucked into the cylinder and lubricate it and should keep the port face nice and clean. You can see a slight build up on poppin now, don't know how long it would take for that to build up and prevent a good seal. I've handed it over to my Dad now who seemed impressed, put a little note in saying "this one works" but have yet to show him.
Another thing I noticed on poppin that alters the characteristics is the spring that keeps the cam follower against the cam. How is that done on yours John? Because it's just a strand of spring wire on poppin it's easy ish to change the tension.
I've never really played with the cam timing because it seemed to run well from where I first set it but I think the thing you can play with is how much before bottom dead centre it closes. Because of the light weight valve it opens when it wants to, when the pressures equalise - I think yours will do the same if your springs are light enough.
Nick
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Hi Nick,
Despite my reservations, I had the original springs set up this morning for a try out, and they don't need to be stretched as far as I thought, so I am going ahead and making some custom spring hangers for them. If they do work out too strong, I have another idea that can still use the hangers I made this morning.
My cam spring is a fairly substantial leaf spring about 1/4" wide by about 1/32" thick, and with all the weight of the operating linkage, it still keeps the ball raced arm in very good contact with the cam.
I do have a fair amount to play with regards to timing, about 10 degrees, also because it will be running on gas, it can easily be throttled, just turn the gas up/down. I have also modded it so that the cylinder can be slid backwards/forwards, giving me control of how close the piston head can be near the cylinder head. I have it set at this time with about 0.002" clearance, so that should be able to completely evacuate the cylinder before the next cycle starts. Just another thing to try out.
John
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As this little engine is progressing steadily towards getting to a running state, I thought I had better do something about the gas burner I will be using.
These are some of the parts that actually make up the gas burner.
I purchased online a new pipe and jet holder plus the right sized jet. For the price they cost, they are not worth making yourself, just a load of machining hassle. Also needed were a couple of end feed plumbing bits, which I managed to pick up while I was out yesterday. Not exactly the correct ones shown on the plan, but they will do just as well.
The plans call for a brass mixing chamber pipe to be made, I don't know why, as it can't be for cosmetic reasons, because it is hidden under the engine, a bit of 15mm copper plumbing pipe will do just as well.
If you look at the plumbing bends, on each flange they have a stamped in safety code. They will look awful on the finished burner, so they have to go.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT174.jpg)
Mounted up onto an expanding mandrel, some good quality cutting lube (standard cutting fluid for copper is tallow, or as a substitute, full cream cows milk) and a change to a new tip soon had them turned off using shallow cuts.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT175.jpg)
There is a little of the lettering left, as it was rather deep, but that will come out in final polish. Looking better already.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT176.jpg)
Next came the four air supply holes for the gas jet and mixing chamber, they were soon drilled in their correct positions.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT177.jpg)
Now ready for first stage silver soldering.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT178.jpg)
I set it up this way to keep the top part in the correct position to the other two pieces. It needs to be totally central in position, not tilted over one way or another. The joints were set up with Tenacity 5 flux and 1/16" easyflo silver solder. Thicker solder than normal was used because the joint cavities will take a bit of filling.
The top joint was completed first, then once set, the job was laid down and the second joint completed.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT179.jpg)
A quick dose, first of steel, then brass wire brushes on the buffing machine soon had it cleaned up enough to go onto the second part of the build sequence.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT180.jpg)
This is roughly where the burner will sit on the finished engine, with the refillable gas tank at the far end, just past the flywheel.
The engine is up on bolts at this time, as I won't be making the wooden bearers until I get well into the finishing off bling sessions.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT181.jpg)
There needs to be some parts made and fitted to finish off this burner, they will be shown in the next instalment.
Bogs
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Hi John, that burner assembly is looking very nice, it looks like it should put out a fair sized flame, and the solder work came out very well, I'm hoping to emulate it with my oddball flamesucker, so it can be speed controlled, as you indicate will be easy for your engine when it is finished. Can't wait to hear it run. :beer:cheers, Jack
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Jack,
The burner will actually be mounted a little lower and closer than shown, so that the centre of the rose is pushing flame to the centre of the valve hole. That way it will be keeping cold air from entering the cylinder, which can be a major problem, especially with spirit based burners, that is why they usually have to be so large.
The flame should be about 1/2" long at maximum, a bit like the individual jets on a gas cooker ring, all the same length, unlike a blowtorch which has the central one much longer and larger.
John
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Brilliant work there John. Good idea making the cylinder able to slide too. Exciting times approaching!
Nick
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Watching and learning, here, John. Flamelickers have always been my favorites. Will your engine run on propane, butane, or ???
Chuck
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It just been better and better :clap: :clap: :clap:
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It just been better and better :clap: :clap: :clap:
So true! :thumbup:
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Many thanks folks for the encouragement.
Chuck,
With a refillable gas tank, you can normally use either propane or butane, as long as you can decant it into the smaller high pressure vessel.
Propane runs a lot hotter than butane when it goes thru the burner, but I normally use a butane/propane mix that is used in plumbers blow torches, very easy to obtain and easily decanted into the refillable tank. I will be showing that rechargeable tank the end of the burner build.
While I am posting this, I may as well show you what I managed to get done this morning, rather than showing it in a much larger post tomorrow
There were three things that needed to be made, on the right, the jet holder clamp, which if made to the plans was all threading and allsorts, this one will just be stuck in the end of the tube with a clamp screw to allow the jet to be adjusted backwards/forwards. In the centre is the mixer venturi, made by drilling thru with a centre drill that has a 1/8" drill point on it. It penetrates half way thru with the 60 degree angled bit, the rest being the 1/8" tip. This not only speeds up the gas flow but mixes the gas and air together. Lastly on the left is the burner rose itself, it has been hollowed out on the back so that the face that the holes are drilled into is only 1/8" thick. This also isn't to plan, I did it to stop the thin 1/16" drill wandering off course if it had to drill the whole depth of the rose.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT182.jpg)
Using the Divmaster and ER collet chuck on the RT, I first went around the rose and spot drilled all the hole positions, then followed the same route with the 1/16" drill
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT183.jpg)
The rose was a tight push fit into the burner tube, plus the tube was very slightly swaged over on the end to make sure it won't pop out when it heats up
The jet holder clamp and the venturi will be loctited into their correct position when I get back to it.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT184.jpg)
I would most probably have finished this burner off if I didn't have a couple of very welcome visitors this afternoon, Stew and Ade V, who called around for a gum beating session and for us to see Stew's flywheels close up and personal, and they are very nice indeed.
All this leaving me totally worn out.
Bogs
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Hmmmmm John, that looks like a big burner? :scratch:
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John,
I think you have to realise that it won't be a roaring burner like a blowtorch, but more of a gentle flame, like a cooking stove burner on low, plus it will be fully controllable by a screw type gas valve. The max flame length will only be 1/2".
We should see tomorrow, if I can get it finished off.
John
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Hmmmmm John, that looks like a big burner? :scratch:
It looks a lot more "in proportion" when you see it together with the engine. I'm well impressed with John's cylinder & piston; you can move them easily, with very little friction; but cover the hole in the end of the cylinder and the vacuum seal is - as far as I can tell - perfect; the piston becomes very difficult to move.
Nice to see you this afternoon John - and, once again, I felt the knowledge basically flowed one way... and it sure wasn't from me..! :thumbup:
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Time to get this burner finished and out of the way for now.
The venturi, sitting in the background, needs to go down the tube from the jet end by a specific amount, so by using the thin depth reader on my digivern, that is what I did.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT185.jpg)
It was a nice 'grippy' fit down the tube, so it was tapped down with a hammer and soft drift until it got to the correct position. I got it to within 0.005" from where the drawing said, and because I have made the jet easily adjustable in/out, the perfect position for mixing can very easily be reached, a few seconds at most. It was loctited in position, as suggested in the build instructions.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT186.jpg)
The jet tube holder was then tapped into the end and again, loctited in. You can see in this shot, the venturi down in the tube, just past the air holes.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT187.jpg)
This is my cosmetically challenged refillable, commercial gas tank, it will be cleaned up and painted.
In the centre of the top you can see the 'Ronson' filler valve, which allows you, with an adaptor screwed onto a disposable plumbers torch canister, to fill the tank with gas (in fact not full, but only about 2/3rds, there is a stack tube below the valve inside that prevents overfilling). These are tested to much higher pressures than boilers, 360 psi.
The control valve isn't a normal steam one either, it has to be a special gas control valve. When I used to make these tanks, from thick walled brass seamless tube and flanged end plates, with an internal stay, the Ronson filler and control valve were always purchased, not made by myself.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT188.jpg)
A thread was put into the side of the jet tube holder and a brass screw fitted. This allowed easy adjustment of the jet backwards/forwards in relation to the venturi.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT189.jpg)
I tried the burner out not only with the brass rose that I had made, but also with a piece of ceramic burner material, made from an old boiler burner.
The brass one gave a much better jet pattern.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT190.jpg)
I hope this little vid shows what you need to know.
Not long to first run now.
Bogs
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Yes, it's a good explanation of the burner, John. Thanks.
Makes a nice soft flame, and is quiet, too. Being quiet is nice, as some are kind of loud.
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You are making a wunderfull engine, the 8th wunder of the world? :lol:
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Crisp, clear explanation John.
Lovely, gentle burner operation. :clap:
A similar design would be perfect for the Robinson engine. Hmmmmm...... :thumbup:
David D
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Thanks for the detailled explanation, John. I've always wondered why the flame doesn't travel back up the tube where the gas and air first mix...
By the way, how difficult is it to blow out the flame with this type burner?
Chuck
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Gents, many thanks, but I think you must remember, I didn't design this burner, I just made it a lot easier and cheaper to make than the one described in the plans, as no materials are supplied with the kit for either type of burner.
Chuck,
Looking at the burn marks on a picture I have of this engine, it looks like the burner is run with a largish flame, maybe to stop it being blown out when the cylinder exhausts at the end of stroke.
I never tried to blow it out, but I suppose I should.
I will have to put my teeth in though, otherwise all I will be doing is blowing raspberries.
John
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John ( Bogs )
if it would not infringe the copyright on the plans can you give the nozzle size and the Venturi dimensions ,if it will then no problems
reason I ask I have a no.5 and no.8 both of which give a flame that is to large even with the valve just cracked I am using the polly/stuart gas pipe and adapter valve for the "go gas cans "
Stuart
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Stuart,
By the nozzle, if you mean the rose, it is the same diameter as the internal size of the copper pipe fitting. The plans actually call for 16 X 1/16" holes, but on the plan drawing, it shows 19 holes, one in the midlle, step out 3/32", then a ring of 6, step out 3/32" again and a ring of 12. I made the 19 hole one.
The jet is a #5, and the venturi is made with a standard centre drill that has a 1/8" drill point, going thru a piece of brass bar the same diameter as the internal of the copper tube and is 5/16" long. The four air holes in the 15mm copper tube are 7/32" diameter.
Read your PM's
John
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I will have to put my teeth in though, otherwise all I will be doing is blowing raspberries.
Now there's an image I really didn't need to visualize.
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Warts and all on here Marv :lol:
Just for a little bit of interest, here are a few pics of this engine, built in the 1990's. It looks like that the build was done exactly to plans, almost. The crankdisk has a different shape.
Just so that you can visualise the general layout.
Looking at it, I think I might knock myself up a shorter gas tank, as the one I have is too long. But I do have a couple more copper based ones somewhere, one of those might fit the bill a little better.
The plans contain all the information if you need to make one yourself.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTTPICS01.jpg)
The linkage to the flame control valve.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTTPICS02.jpg)
A close up of where the burner sits and how the graphite block seems to sit in the burner flame almost permanently. I think I will have to knock up a few spares as I expect they will get burnt away.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTTPICS03.jpg)
It also looks like they have reduced the top to bottom height of the block, I will have to look if that is required when I get mine to a running stage.
Just by looking at other peoples builds can give clues to little problems that might need fixing before it will run correctly.
Bogs
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Thanks John
Pm read and actioned
Stuart
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Hi John, it looks like that burner came out very well. I've been running my "oddball", with just the light of the overhead in my shop, so I can look through the port and watch how the flame plays through the hole. I've got an inch and a half stroke, three quarter bore, with a three eighths port, using a nine thousandths leaf from a feeler gauge and about a .213 brass tube with cotton string for wick, and I see a half inch diameter flame "ball", a soft flame, as the port closes, and about an inch or more of flame going fully into the cylinder when fully up to temp, running about six hundred rpm. I think a gas burner out of perhaps three eighths copper fittings, scaled down comparable burner plate and venturi, will probably give me a bit more flame than my alky lamp, and probably allow me to cut it in half, for a slow run as well as the full out speed. I've had the soldered together valve linkage break the solder joints from letting it get up to about seven hundred rpm, it's soldered a bit better, but I suspect I'd better put a bracing brass tube to triangulate the linkage or a better flame will cause another breakage.
That burner build section is very well done, and clarifies things a lot, making for some ideas on a similar burner for a sort of version of "poppin" I've been working on. I want to get away from the alky lamps and go with the gas as much as possible. I've used one of those torch type lighters with butane, and the strong flame doesn't do near as good a job as the soft flame you're getting and seems to draw in cold air as you suggested. I'm trying to get my oddball a bit easier to operate so I can give it to my mom, I think she'll enjoy it, especially if it's easy to clean up, and easy to get it to run right off cold.
I think the narrower tank looks good on that other build you show, and will look good on yours too. I suspect the graphite will last pretty well, as it stands almost red heat pretty easily, and it doesn't conduct heat very well. The way this build went I'm thinking I need to emulate it, it looks to be quite efficient altogether. very nicely done, and with very nice graphics, I really like the vid of the burner, and the narrative you give with it. Very informative. :beer: Cheers, Jack
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John, at first sight your burner seemed to have a lot in common with a laboratory Meker burner, which according to one source I have seen produces (on natural gas) 12,000 BTU/hr as against 5,000 from a Bunsen. Pic of a Meker here: http://www.crscientific.com/mekerburner.html . Thus, I thought you might get a rather roaring flame, but the lack of a "specially designed barrel" on yours, and the turbulence caused by the bend, probably keeps it in check. Nice job; looking forward to seeing it powering the engine.
Andy
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A little more slow progress. I have been trying to sort out a decent spring hanger method, rather than the crappy ones shown on the plan and what you can see in the few piccies I showed last time.
This is how I got on.
The ones at the back, I incorporated into the valve arm hub, and by measuring that up between the arms, I managed to get a length for the graphite block to lifting arm spacer, so a couple of those were knocked up out of brass.
Once that was done, a quick measure up between the back spring tails and I could start to make up the top hangers.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT191.jpg)
This shows where the springs have to stretch to, plus it shows how the cam follower and lifting arms work,
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT192.jpg)
After an hour or so's work, the top hangers were made. The bottom left hand one has slipped on the shaft slightly as the grub screws have yet to be tightened, but you can now see that the springs are now well secured and running parallel with the operating arms, rather than the haphazard way they are suggested to be mounted.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT193.jpg)
How they sit with the cylinder and water jacket fitted. I started to set up for a very basic try out, with the grub screws all tightened up and the timing somewhere near. I am going to have the engine with the flywheel running clockwise when viewed from this side of the engine, rather than from the other side. That means the flywheel retaining pulley screw is tightening up during running rather than trying to unscrew itself.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT194.jpg)
Unfortunately, I failed miserably.
I was attempting to run the engine with the cam follower arm retained by a grub screw onto it's shaft rather than a pin right thru it. I did that for ease of disassembly during trials. It kept slipping, so it looks like I will have to pin it now rather than later. Also, I need to shorten the studs slightly that hold the cylinder head on, the graphite block spacers are just touching them. Before going ahead and shortening them, I will make and fit the cylinder head gasket first, that just might give me the clearance I need.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT195.jpg)
Getting there slowly.
Bogs
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Looking good John
It would be great if someone could do some macro/slow motion video of the flame propagation though the port on a flame gulper engine
Stuart
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Stuart,
I was looking at purchasing a new camera to do just that, a Casio model, but having not long ago bought a new Fuji one, I thought it a bit of a waste of money just for the slomo feature, so maybe in another years time.
I will be happy just to see it running.
A job for today, hopefully.
John
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Hello John,
I've been following your build and am, once again, very impressed with (A.) your craftsmanship, and (B.) your inventiveness - congratulations on what will inevitably be another great engine. Love the idea of the gas burner as well as the graphite valve. Lots of ideas for the file for future use!
Best,
Mike
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Very nice John, the parallel springs look a lot neater it seemed a bit of an afterthought on the original design nevertheless functional. There's always something like the grub screw issue that crops up. Similar thing happened on mine, it wasn't tight enough and moved.
I expect it's probably ticking over now as I speak ...
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I will be happy just to see it running.
A job for today, hopefully.
John
Good Luck! :thumbup:
David D
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Definitely getting there John :thumbup:
My camera has a slow motion function on it... But I've never tried to get anything transferred to the computer... I'll have to see if it's possible?
Some of these things use the internal trickery and it doesn't work on the big screen? I'll let you know.
Ralph.
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Twice at lunchtime today I tried to get this post written up, but both times I failed miserably, purely because I wasn't feeling up to it.
So now here is the belated post.
I need to carry out a few little mods to get this engine up and running, so this post concentrates on two of them, mainly how to make gaskets, which I will be showing in full, so that maybe a few people can pick up a tip or two.
I am making this head gasket for three reasons, the first is to seal the cylinder from the outside world, second is to attempt to stop a lot of heat transfer to the cylinder and water jacket and thirdly, to make the studs shorter so that they don't interfere with the valve operation.
I swear by different thicknesses of PTFE for making gaskets, it seems to have no bad faults at all, only good, when used in this context.
So getting a piece of 0.015" thick of about the correct size, the OD of the head was marked on it and the centre found.
Take note of the real el cheapo compass cutter that was bought for a couple of squid a few years ago off a market stall, for cutting these circular gaskets, I just couldn't live without it.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT196.jpg)
I used to really struggled trying to cut circles with this cutter until I found this method.
I stick both the centre pin and blade thru the material and into the wood underneath (not too deep) and holding onto the top of the compass to keep it steady, I rotate the gasket material against the cutter blade, rather than trying to use the compass like you would normally use it.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT197.jpg)
If you get your blade to pin measurement to size, and cut it how I have shown, you should end up with a perfectly fitting gasket.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT198.jpg)
The next trick is using another indispensable bit of kit for use in the workshop, transfer punches. I have duplicate sets of these in Imperial, metric, number and letter sizes. I use them not only in their guise as transfer punches, but also used instead of drill blanks, which are very expensive indeed. In fact, all my sets of my transfer punches added together only came to the price of one set of good quality drill blanks. How accurate do you really need to be in the home shop, these are well within 0.001" of drill blanks, if not even closer.
The gasket material is slightly transparent, so it was easy to align the top and bottom holes up, then it was just a matter of pushing the correct size pointed transfer punch down the hole until it marked the gasket.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT199.jpg)
I didn't push hard at all, but all holes are well marked up, and in an accurate position.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT200.jpg)
The holes were easily punched out with a tube punch, and the finished punched holes fitted perfectly onto the water jacket studs.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT201.jpg)
Using a couple of general screws and nuts, the gasket was trapped between the cylinder and it's head. The material around the outside was carefully cut away, very close to the metal.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT202.jpg)
Resulting in a perfect and long lasting gasket.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT203.jpg)
Once all assembled up, you can now see that the threads don't protrude as much thru the nuts, so that is one problem cured.
It looked like a long process, but in fact took well less than half an hour.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT204.jpg)
This fix is nowhere near as complicated.
The plans call for either a taper or roll pin to lock the brass part onto the rod. I hate using pins, purely because they can sometimes be very difficult to get apart once in position, this would be just the case here.
All I did was to accurately drill right through the brass bush and steel rod, then tapped it out 2mm. A recess was put in to take the cap head. Now I can take it apart very easily whenever I want, but stll have very secure fixing. The original grub screw hole (hiding around the corner) will be filled with a bit of brass threaded rod, and by the time I have finished blinging, will never be seen again.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT205.jpg)
I'm sorry I didn't make any more progress to show you, but I have to take each day as it comes.
Bogs
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How to make a round gasket.
Thats brilliant John. :clap:
Dave
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Nice I love it. :clap: :clap:
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Kenneth,
I have never had any trouble with this stuff, even when I used it for head gaskets on ic engines.
Maybe problems could occur if you started to get into elevated heat situations, but hopefully, none of my engines will ever reach that stage.
I do know that they had a bit of trouble on full sized steam engines with PTFE tape for sealing joints. But they are working at much higher levels of everything compared to our small offerings.
Bogs
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John
looks like you have the same gear as I do for gasket production
I do mine slightly different measure the ID , OD . Then I cut the OD with the compass/cutter then follow up with the ID . The reason I do it that way is most of the places I need a gasket for precludes the application of the knife on the OD
toes crossed although it will not be necessary for a runner this week
Stuart
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Stuart,
I would normally cut the outside first as well, but in this case, I wanted it exact to size, with no chance of it being too large or small. I got what I wanted, which is what it is all about.
I have been on about getting this engine up and running for so long now, I am giving no more predictions, it runs when it and I am ready. My work regime, as has been shown, can throw any predictions to the wind.
John
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Continuing on, getting things sorted in the hope that I can get some power out of it.
A few revelations after I got things done, I will explain a little later.
The grub screw holding for the valve lift arms needed beefing up a bit and to get them gripping properly, flats were required on the cross shaft.
With the cam set to give maximum lift and a machinists jack holding the graphite block in the correct position, by using a transfer punch down the grub screw hole, the shaft was marked up where the flat needed to be.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT206.jpg)
By mounting the shaft in the milling vice with the pop mark at the very top, a flat was cut on either end.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT207.jpg)
Next came the grub screws themselves. I had been using stainless ones, but unfortunately they are always rather soft and you can soon round out the allen key hole if you give them a bit of white knuckle treatment.
So for this job I went back to my normal high tensile steel ones after I had ground the ends flat so that they will sit correctly on the flat on the shaft.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT208.jpg)
By the time I had finished twiddling about it was time to try to get some life out of the engine, so by jury rigging the burner in position I gave it a try.
By playing about with the timing for ten minutes, I knew that I had it spot on, plus I had to do some serious bending of the cam follower rod to get things something like.
A few minutes later, I had it turning over a couple of times by itself, and I can now tell you, it is another 'duck quack' sounding engine.
But no matter how much I tried, I couldn't get it to run continuously. Then I noticed something quite alarming, as the cam is, it does not allow the inlet port to be fully uncovered, so the graphite block is in fact stopping the flame reaching the port correctly, hence the lack of continous running.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT209.jpg)
I am now going back to the drawings and check out all the geometry of the cam and lifting arms. I built everything to plan, and all that has been double checked at least twice, so it isn't my making at fault, but the basic design which hasn't been modified to show what is required to actually get the movements required to have the engine running.
I can now see why, on the engine I showed earlier, they had actually made the block a lot narrower, and as I suspect, they had the same problems as those I am finding now. I don't fancy making a higher lift cam as that will raise a few clearance issues, so, because I have a load of graphite I can play with, I am going to see if reshaping the graphite block will improve things in the running department. That might also mean I will have to make a new cross shaft with the holes in a different position, but I can get around that for the time being by bending a few brass arms.
It's all part of the game
Bogs
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Looking good John
It makes me wonder if there is a "perfect set of plans out there for anything in the model world ( except your paddle duck ones ) I have spent good money on plans and they mostly contain errors , the older LBSC ones are the worst the dealers just keep duplicating the masters they have and do not update them but keep charging the same ever increasing price .
rant mode off
it is a disappointment to me that the poor sole that has limited skill/knowledge can be put off because of the faulty plans
Stuart
ps got the rampant gas burner under control now thanks
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It's all part of the game
Bogs
"Final adjustment, and tuning", eh John? ::)
Good luck! :thumbup:
David D
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Great work there John, sounds like you're nearly there and this trouble shooting is obviously brilliant info for somebody contemplating building it themselves. :thumbup:
I must admit, I thought this one would run straight 'out of the box' though. I'm a bit disappointed that a design that's been made commercially available has not had adequate testing and the design hasn't been revised accordingly. Will you be going back to Bruce with your findings or just accept that it's just the way it is?
We now have quite an extensive knowledge of flame lickers and know that they are tempremental beasts. However, as Stuart said, the unsuspecting modeller could spend quite a bit of cash and put a lot of time and effort into machining one and not get a peep out of it. In which case it'd probably end up under the bench which can be quite upsetting. Many people wouldn't have a clue how to go about solving the issues either.
The valve / linkage geometry and cam is very similar to that of poppin and from the last picture it looks to be timed very similarly to mine, shuts about 45 deg before bottom dead centre? Apparently it isn't even that critical with this type and mine would go along with that as it ran in the first position I put it in.
Great photos and workmanship by the way.
Cheers
Nick
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Before I give comments on whether this engine is suitable for a beginner or not, after I get it running, I will be contacting Polly models about what was needed to achieve a running state, and depending on their reply, I will give it thumbs up or not.
I have been trying for a few years now, in my own little way, to give feedback to suppliers. Some just totally ignore you, so to me, they are not worth dealing with, but others, like Minimag, took on almost everything that I found issue with when I built their magneto, and remedied the problems on both the plans and build notes. In that situation, the supplier gets a big thumbs up :thumbup:, purely because they have the customer in mind as well, rather than just the profit margins.
I don't know if you noticed the Chronos website, last year it had a major revamp, and I hope to think that it was helped along because of my complaints to not only Chronos, but to PayPal as well, about how bad their site was. Showing items in stock, taking payments for said items, then a week later giving you a PayPal refund because they didn't have stock of the item you had ordered.
They actually stopped me ordering from their site, until I had another quiet word in PayPal's ear, after which time, Chronos' service has improved no end.
The other two 'biggies' in our supply world in the UK, Arc Euro and RDG both took on board a few comments either about service or products that I mentioned to them, and both remedied the situation very quickly, so they get full marks from me.
So no matter who you are, sometimes it does pay to contact suppliers and let them know how you feel about their service or products. If you don't let them know, how are they to put things right? If they are any good, they will do something about your comments, if they don't, just let the word out who the 'nasties' really are.
John
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Good point John, that's what I was thinking - they should be made aware of your findings but they should want feedback like that. I bet some people can't be bothered to feedback but if we don't we'll always get a crap service. On the plus side, the quality of the kit and castings looks relatively good.
I'm guessing that not actually that many people have built this engine though.
Nick
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You might be quite right Nick, I have never seen one before whilst going around the shows.
But on the other hand, maybe lots have been built, but can't be got to work, so are gathering dust somewhere.
There were no major issues with the castings or materials at all. With a little work, they were all perfectly useable and not one single inclusion, so they get a thumbs up :thumbup:, and for the price paid, I found very reasonable value for money compared to the garbage some suppliers charge for unrecognisable lumps of junk.
John
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John
With regard to your post on using PTFE for gaskets , I was helping the SWMBO to clear out some kitchen draws ( done some wall painting in WS so as it stinks it is OB ) I came across some thin black stuff that has a reinforcement in it , so I asked what it is , Linda told me it is the off cut from the liner from the bottom of the oven , If it can stand the oven temps the bit in the oven shows no degradation . Would you think it could be used for higher temp gaskets ?
I know its not an engineering site http://www.lakeland.co.uk/magic-oven-liner/F/product/3318?src=gpsol&sq=oven%20liner
Its about 20 thou thick
as I mentioned the stuff has a fabric type reinforcement layer so may be more stable in creep
Stuart
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I have no idea Stuart.
I personally don't like the idea of it having some sort of fabric in there, giving it a surface texture.
When I bought my PTFE sheets, I stipulated that I didn't want an etched surface, but totally smooth. Gases will take the shortest route possible, and if it can fast track along a surface pattern to the outside, then it will.
John
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Hi John, it's good to see such progress, and getting to the nitty gritty. In looking at that engine design, particularly the couple I've seen completed, including the one you show, I noticed the block of graphite sits blocking substantial flame propagation, and my experience with these engines is they are completely dependent on good flowing characteristics, with burners well positioned, and minimal interferance with smooth flow. I had to alter my valving on my own oddball several times, ending up with an "upside down" version of the "poppin'" valve in order to get good clear flow, and consistent running. I'm building one now, which will be posted shortly, and I'm considering using your valve arangement, but with some modifications precisely because I don't like the valve, whether bronze, steel or graphite, substantially altering the flow pattern of the hot gases during the intake stroke, as it is entirely atmospheric, and therefore easily disturbed causing substantial eddies and other interferances which can reduce actual intake of the heat by substantial amounts. I'm still finishing up the con rod setup, and have the head roughed, and have been waiting to see how this build turned out before deciding on valving. I'm wondering if you should have your valve going up, above the port, for the opening, giving the flame a less impeded flow than going over the block. I suspect this is also why others have rounded the graphite block or put forty fives on the corners, to lessen the flow interferance. Other than difficulties in starting, it has turned out very nicely, and I think you will easily conquer the problems with the valving. I am looking forward to devising a burner for my oddball, based on the demonstration of your burner design, and it's fine flame propagation. Waiting with increased anticipation for the running video. :beer: Cheers, Jack
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Jack,
No chance of anything soon, I haven't even been near the shop for a couple of days, and it might be a few days longer yet.
Everything you have mentioned I have already chewed thru.
John
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Hi All,
Beautiful machine there John. Always very enlightening to read your methods and learn from the oddities you discover and correct for. :)
I was looking at the engine, and thinking about the graphite block, and the clearance issue you had with the threads earlier, that were corrected by the gasket.
Does the graphite wear over time? ANd or need to take a "seat" on the surface as the engine runs?
The reason I am asking... the head nuts/studs you have.. the two on each side protrude, and I was wondering if you will encounter clearance issues once the graphite wears down a bit from sliding up and down on the head...
Its been a long AM, so I may be off with my thoughts.. but I was curious on that one.
Beautiful Machine
I hope the pain in your bod gremlins leave off. I Know my wife has good and bad days as well. so I truly understand my friend.
Scott
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Scott,
All the clearances have now been sorted, the block will have to wear down to a point where the engine will not continue to run before anything fouls again.
This is a very quickie post as I am having site access problems.
Just one pic at this time.
As I said, I needed to check out the geometry of the plans. I just used basic pythagoras for working it out, not wanting to bring operating arcs into the equation, but the information that it gave me showed that I have more than enough movement for the block to work correctly.
I also reshaped the block to what I thought it needed, but I will have to show you that next time, as I haven't taken any pics of it yet.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT210.jpg)
This is the reason for no piccies. I wanted to try it out first, just to see if I had my calculations right.
I seem to be gasping for air. In fact I am just recovering from a chest infection and a cold, hence I haven't been in the shop for a while. But within 10 minutes of getting in there this morning, the engine was basically up and running, not too well, but plenty good enough for me to see that it has potential. The sound has changed from a 'quack' to an ic engine exhaust sound, and unlike the other flame licker I built, this one has useable POWER :clap: :clap: :clap:, so maybe a little generator might find it's way onto the scene.
Bogs
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Good work
Looks like you have it sorted
Stuart
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Wooooo I thought I heard a big cheer go up over your way this morning.
:clap: :clap: :clap: :clap: :clap: :clap:
Nice one :thumbup:
Stew
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Well done John :clap: - congratulations !
Kind regards, Arnold
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Hi John, I think that cheer Nick heard came from North Carolina. It sounds good, and I'm sure you will get the little things worked out and have a genny on there soon enough to show us. Congratulations on a fine looking and sounding engine. Very nicely done, and very well documented. :nrocks: :beer: :bow: Cheers, Jack
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Big, happy smile time! :ddb: :ddb:
Well done John! :clap: :clap: :thumbup:
David D
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Many thanks indeed gents for the good comments.
It has taken me a bit longer than I thought it would, but that is life.
I will take a pic of the modded block, then I will be shutting this post down for a bit, while I get it all put together correctly and blinged up. Hopefully by the time that is done, I will be able to control the speed.
John
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I really like the sound and the interesting motion of the intake mechanism. Pretty exciting to see it run!
Thanks for the vid, John.
-
that runs a treat well done :thumbup:
Graham
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Great work John! :bow:
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It'll do :thumbup:
Sounds like it's got plenty of umph :headbang:
Ralph.
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Nice one John - this engine looks great.
Chris
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Thanks for all the praise lads.
I would just like to say, all the prep work I had done beforehand really helped, things like getting the cylinder, piston and bore spot on square and lapped in.
Once I had the block reshaped, there was absolutely no mucking about at all, I put the flame to the hole, and away it went, not one drop of lube required anywhere.
But anyway, just a few pics to show what I had to do to the block to get the flame to the hole. The flame sits at an angle of 45 degs, so I reshaped it so the flame had a nice long runup.
Just as a reminder, this is what the block looked like when made from the plans, the top angle wasn't long enough to get the flame to the hole, it was blocking it's access.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT171.jpg)
About 0.050" (1.25mm) was removed from the bottom of the block to allow it to drop a little lower, as it was nearly touching the two lower nuts when at full drop. The top 45 deg edge was machined to be a lot longer.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT211.jpg)
Just another view.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT212.jpg)
Now I can take my time getting everything 'just so'.
Bogs
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Well done John, it's spot on. :thumbup:
I'll still be watching for the bling as this is going to be some engine. :bow:
Nick
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Very Nicely done!
That bad boy sounds really nice. Good thump to it.
Seeing the motion of the block moving up and down, It doesnt appear to get up to the studs, and appears to move really nicely!
Really nice work there, once again. Top notch as always.
Scott
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Hi John, that valve looks great, it ought to do the job right well, and I'm looking forward to the video. :beer: cheers, Jack
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Jack, think you've missed a few posts there, the video is on the previous page! :thumbup:
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Nicely done John :clap: :clap: :clap: :clap: :clap:
She sounds great :thumbup:
Rob
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Jack, think you've missed a few posts there, the video is on the previous page! :thumbup:
Nah! I just want to see it run with the valve altered and see it improved :lol:, you know, you make a change, ya got to document it and show the improvement :poke: :beer: cheers, Jack
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Scott,
All the clearances have now been sorted, the block will have to wear down to a point where the engine will not continue to run before anything fouls again.
This is a very quickie post as I am having site access problems.
Just one pic at this time.
As I said, I needed to check out the geometry of the plans. I just used basic pythagoras for working it out, not wanting to bring operating arcs into the equation, but the information that it gave me showed that I have more than enough movement for the block to work correctly.
I also reshaped the block to what I thought it needed, but I will have to show you that next time, as I haven't taken any pics of it yet.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT210.jpg)
This is the reason for no piccies. I wanted to try it out first, just to see if I had my calculations right.
I seem to be gasping for air. In fact I am just recovering from a chest infection and a cold, hence I haven't been in the shop for a while. But within 10 minutes of getting in there this morning, the engine was basically up and running, not too well, but plenty good enough for me to see that it has potential. The sound has changed from a 'quack' to an ic engine exhaust sound, and unlike the other flame licker I built, this one has useable POWER :clap: :clap: :clap:, so maybe a little generator might find it's way onto the scene.
Bogs
Try hear
-
Jack,
The video was with the modified block.
I couldn't get the engine to give a sustained run with the block as made from the plan.
John
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My fault, John, I wasn't paying proper attention, but I definitely like it and think you will get it all spiffed up and working driving something, and fit out as you want rather soon, a very entertaining and informative build, and the water cooling is very intriguing as well, quite a nice piece of engine in my opinion. :beer: Cheers, Jack
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Jack,
I am actually having to do a little bit of private engineering for the next week or so, but I will be doing the finishing off a few things in slack time.
I always get my engines running before polishing up and painting, saves spoiling the finish trying to get them to run.
There are in fact a lot of parts that still need to be made, the wooden bearers, which might not sound much, but I am looking to get a special finish put on them which will take a while, plus I have also decided to make a new rechargeable gas tank of the correct size rather than cobbling one up to fit. That will take a while as it requires to be pressure tested to 360psi. I need to find someone locally who can test to that high, as my steam test gauges won't reach that high.
So you have only really seen the basic engine being made, not the far from finished article.
John
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Having got most of the flywheel tidied up, just requiring a few more hours to finish it off, I decided I need to make the combined power takeoff pulley and flywheel/crankshaft clamp. For models such as this, which don't have too much power, I prefer not to drill or make special fittings for the flywheel, that way, they always run nice and true. The crankdisk is first locked on, then using spacers and other components right the way along to the other end of the crankshaft, the whole lot can be tightened up together, as long as the flywheel turns in the correct direction for tightening up the screw/nut.
For many years now, I have been picking up very old sash weights from the scrap yard for pennies each (on average 30 pence, about 50 cents US). These give me a great source of very fine grained cast iron up to 1 3/8" diameter.
I stuck the weight onto my power hacksaw and soon had a 2" long lump for my use.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT213.jpg)
Unfortunately, with these cheap materials, you have to put a bit of work into it to get the good stuff out. In this case, the hard casting skin, which if attacked with a normal pointed carbide tip or HSS they would be flattened or broken in seconds.
I use the wide angle part of the tips in a special facing roughing tool holder.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT214.jpg)
The same goes for the main outer skin, another type of roughing cutter removes it very easily.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT215.jpg)
Very quickly, I was the proud owner of a piece of over 100 year old, super fine grained cast iron bar.
So a C-o-C was drawn up to give me a working drawing of what I wanted.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT216.jpg)
You may have noticed that I am working with my lathe in 'Myford' mode, I will be swapping this chuck over onto the mill RT once the pulley has been roughed out.
The outer face was relieved a little for when I get it onto the mill in the final stages for cutting the half round drive belt slot.
Both sides now needed a 7mm deep recess cutting into them. So a quickie grind up on the offhand had a rough trepanning tool that will do the job. It left a few chatter marks on the bottom face, but I was not worried about those, they can easily be cleaned up later.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT217.jpg)
This is where it will be mounted when finished, compressing everything up nice and tight into one long unit.
Notice how nice the finish comes out on this material, no polishing was done at all, just basic deburring.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT218.jpg)
Basic lathework done, time to get onto the RT to have a bit more machined off it.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT219.jpg)
After some very rough calculations, and by use of the Divisionmaster, I had all the holes in the right places.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT220.jpg)
Then it was just a matter of joining up the holes using the X & Y axis of the mill and the RT in manual mode.
I also put a few more slots in as well, as shown on the next pic.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT221.jpg)
This is an awful pic, it looks like the spokes are all twisted and the wrong shape, but in fact, I hadn't deburred it before taking the shot, and what you are seeing are mainly shadows from the heavy burrs being thrown up by the flash on the camera.
Once deburred and cleaned up with a bit of filework, it will look spot on.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT222.jpg)
This will now be put to one side, until the flywheel has been finished off, and when I have the RT set up to vertical for another job I am doing, then the half round slot can be finished off.
Bogs
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Bogs, this is art, it should be om an museum :clap: :clap: :clap:
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This is coming along very nicely. As usual, your write-ups are very educational, and even though I have no present plans to build a flame licker type engine, I am still learning a lot from your build log.
For instance,
I use the wide angle part of the tips in a special facing roughing tool holder.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT214.jpg)
Now there's a useful tool, thank you for showing that :thumbup:. I have a number of ccmt inserts that have the pointed tips dulled or chipped, but I hadnt had the heart to chuck them out yet. Now I am glad I kept them. I will have to look into getting or making a holder like those you've shown so I can make use of the shorter cutting tips.
Tim
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Tim,
I think Chronos sell those alternative holders. I got mine from there as a full set, expensive, but worth their weight in gold.
I was talking thru Skype to a member from Africa last week about how you can use the wider part of these tips, and he was dumbfounded, he had just thrown away all his sharp end blunted tips, not realising the other two points can be used as well.
If you go to this site fairly quickly, before anything else is posted, the first article shows what are available for use with these tips.
http://start-model-engineering.co.uk/
SCKCR is the facing version and SCBCR is the outside roughing tool.
John
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Dumbfounded - more like devastated :(
I think I have thrown at least 100 away. Thats 200 cutting edges. :jaw: :doh:
Daveh
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Long time lurker - long time reader of Bogstandard's adventures. Thank you for the usual wonderful pictures and the inspired machining. Your attention to detail is amazing. :clap:
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Dick,
Thanks for the nice comments.
I think you will find, when I am in bling mode, things get done in a very haphazard way. I will pick up one piece, do a bit, then put it down and do something on another piece, eventually things start to look right together.
It isn't all shine, I tend to place emphasis on the shape, and worry about how I am going to get it cleaned up and polished later.
A little recess or chamfer in the right place can change the whole look of a part.
There are a couple of people much better at it than me that spring to mind.
Divided He-ad (Ralph), is a master of curves and how to put them together in the right order, and Cedge (Steve) for super fine detailing.
Bogs
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I just thought I had better prove that this bit would come up rather well before everyone forgot what it originally looked like.
I spent a couple of easy hours this evening, just cleaning up and putting the curved face on top of the pulley. I have still yet to put the half round groove in, plus the threaded stud.
This is the main bit you will see.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT223.jpg)
Plus the bit you won't.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT224.jpg)
It is such a shame to cover up most of the finger work with a coat of paint, but hey! that is what it is all about.
Eight spokes, just like the big one, but in a different configuration.
It hasn't come out too bad seeing it started off as a lump of unwanted scrap iron. All you need to do is look at that old bit of metal, and visualise the beauty within.
It is up to you then to get that piece out of it. Material cost, about 5 pence.
Bogs
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It's beautiful, Bogs. Certainly the silk purse from a sow's ear.
The old rough sash weight found a new life in your shop.
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I actually tried to post this yesterday. But with the current site issues I'm copy and pasting every post I make into my note pad and then saving it.... Cunning eh? Well, not really but it meant I didn't have to re-write it all :thumbup:
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There are a couple of people much better at it than me that spring to mind.
I'm not in that category John... Yeah I can spin up a few curves. But I can't seem to finish anything of late and I can't get 'em running right when I do!
Got to be a full package including a good performer to be classed as better surely? Let alone much better!?
Cedge on the other hand...I fully agree. Some stunning works in the last few years :jaw: (where's he hiding anywho?)
Anyway... Have you forgotten to look on the sideboard?The mighty mill engine is awesome and the finger engine screams BLING!!! :thumbup:
Nice work on the take off pulley too....
There are a couple of people much better at it than me that spring to mind.
Simply not having it! :wave:
Ralph.
(nearly forgot to save this! :loco: )
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I just had to get this bit out of the way, so instead of waiting to stand my RT upright, I did it with the spindexer.
Having set up the spindexer in the vice, I first positioned the cutter half way across the face, where I had cut a relief into it. Then with the cutter tip a few thou lower than centre, I just fed the cutter in from the side and gently hand turned the spindexer in an anticlockwise direction, so that the tip of the cutter was doing all the work.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT225.jpg)
I just kept feeding the cutter in a bit, then doing a revolution, then feed a bit more, until I got to the depth I wanted.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT226.jpg)
After tapping out the centre spindle and fitting in a bit of stainless studding, I could use the pulley to fix the whole flywheel shaft together. Everything ran nice and sweet and true.
This shot shows how the spring belt will work, hopefully the other end will be going to a small generator.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/From%20June2010/SCOTT227.jpg)
Just a bit more work on the flywheel and these two bits will be ready for paint.
Bogs
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I do like that method of putting the round groove into pulleys etc.
It's the one you showed me when I was making the pipe bender. It works a treat and so very much simpler that grinding up form tools for the lathe. I like simple! :thumbup:
Another interesting way to fix a flywheel too. It's all going into the memory banks :)
Ralph.
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Neat way to cut the radiused groove, John. I hope I remember that one!
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It's a very easy way to do it Dean.
Saves having to grind up radiused cutters for use on the lathe, all you need is a milling cutter of whatever sized groove you want. As Ralph said, when making a bending machine, it is a simple job to make up the bending rollers to fit any diameter pipe, and they fit the pipe perfectly.
John
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Very nicely done, John. I tried a piece of sash weight once and gave it up as a bad job, but I think I'll take a different approach with one next time, I liked how that pulley turned out and the technique with the groove as well. I'm looking forward to seeing it turning the gennie. :beer: Cheers, Jack
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Jack,
It seems that US sash weights aren't made to the high specs of UK made ones. I just cut off 3" to 4" of the end opposite to the cast in loop, and that gets rid of all the dross, the rest is then perfectly useable. 12" to 13" of 1 & 3/8" diameter of fine grain cast iron.
I have forgotten the number of little engines and parts I have made from them, and I have enough in stash to last the rest of my natural, so the saying, 'I'm OK Jack' comes into play.
John
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Hey John, that's a neat trick using the the end mill to cut the groove in the pulley. By the way, is that an ER Collet on the spin indexer? Did you make it?
Chuck
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Thanks Chuck.
Actually, the ER collet system on a spindexer is in fact an idea by our own John Stevenson, and they are retailed by Arc Euro.
About half way down the page is the spindexer, but if you go to the very bottom, you will see a 5c to ER32 adapter, I am sure you could knock one up out of a blank 5c arbor, like I am doing at the moment with other types of fittings. At this moment, I am part way thru making a 5c to R8.
http://www.arceurotrade.co.uk/Catalogue/Collets/5C-Fixtures
John
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John
Another great "how to' build from you. I've not been following up to now as I've been doing my own stuff that has kept me away from forums to some degree. Looking forward to its imminent completion.
One minor point; way back I did see reference to "this is going to be imperial measurements and BA threads" then I noticed some 3mm studs crept in (or didn't they in the end).........
regards
Pete
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Hi John, I wanted to say how much I enjoyed the whole log, but the particular parts that were learning lessons. That deal with the end mill and the pulley is great, I made a tubing bender for motorcycle frames, went through three different iterations, making "pulleys" for each, the hard way, and since I will be making another version, having learned from this last, I will be making another "pulley" with an inch groove, but the groove will be more accurate, and far easier to machine, using your method. I also questioned the thinning of the burner cover, and have made a similar burner, only out of 3/8ths copper pipe, for the smaller engine, and used a .046 drill behind a #1 center drill, drilling some .310 deep, and when I cut it off, faced it, and got it all cleaned up, the back side looked dead on target, and there are obvious signs of drill wandering in the .300 thousandths of drilling, so I will be making the next one much thinner, your instincts being dead on right. Not enough wandering to make it not work I expect, but I'd rather the pattern be accurate on the burner face, and I expect the length of the holes will have some effect on the direction of the gases coming out to burn. I will be testing it out shortly, and will post the results on the log I started just for gathering ideas and brain storming on these engines. I'm hoping that will stay around a while, and let more people start with a simple engine, and not have them, as you point out, sitting on shelves not running, when it generally is a pile of niggling details together stopping it, and not just one big error. I don't have a ready made orfice so I will be trying out my own set of small jet drills, and hopefully will find one that works well with the pipe size and the nineteen holes in the burner head. Again, a very well done and easily followed build log that has been very informative. Wish I could still smoke :poke: :lol: I miss it a lot, even twenty years later. :beer: Cheers, Jack
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Pete & Jack,
Little would you believe, this post is far from finished with. I am actually in the finishing stage of components, and no one wants to see picture of little bits of filing that have taken a couple of hours to do. The flywheel alone has had hours of hand filing put into it already, just to get the spokes something like I want them to be, and I am a very slow worker, only being able to do so much at any one time, hence my dropping onto other machining things, once my hands get tired and useless from filing.
As and when I finish a major piece, I can show a piccy or two.
Personal things have now taken over again, and I most probably won't be as active after another couple of weeks. But it will get finished.
John
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I found a little bit of info last night that might come in handy for those who want to try the gas route.
In the UK we have standard jet sizes, and the one I used in the burner on this one was #5.
Number 3 which has a 0.15mm dia jet bore
Number 5 which has a 0.2mm dia jet bore
Number 8 which has a 0.25mm dia jet bore
Number 12 which has a 0.3mm dia jet bore
Number 16 which has a 0.35mm dia jet bore
All have 1BA thread on holders.
Bogs
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Hi John
Were do /did you get that springy stuff you using as a belt :dremel: :)
Rob
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Rob,
That 4mm spring drive belt used to be used on some old envelope making machines I used to work on. I used to take home the offcuts from the ends when we fitted new ones.
Mamod use 3mm size for drive belting
http://shop.ebay.co.uk/?_from=R40&_trksid=p5197.m570.l1313&_nkw=mamod+drive+belt&_sacat=See-All-Categories
I suppose I could let you have a couple of feet of the 4mm stuff if you need that size. I will be using the 4mm one on my R&B for the governor drive.
John
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Cheers John :thumbup:
I orders some from Ebay :ddb: :ddb: :ddb:
Rob