MadModder
Gallery, Projects and General => Project Logs => Topic started by: NickG on November 02, 2009, 05:40:37 PM
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Hi all,
Well, I've finally got my butt back in the workshop and started my next project. I am on leave all week so the plan was to spend 2 hours in the morning and 2 hours in the evening each day, the aim being a completed project.
After a bit of deliberation I've decided what I'm making.
Here are some of the materials:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0220-17-15_0001.jpg)
Any ideas? This pic might give a better clue:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0220-17-31_0001.jpg)
The wheel was an old casting I got many years ago and machined quite badly but never used it on anything. I thought I could probably put it to some use now so I set about trueing it up in the lathe.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0220-59-28_0002.jpg)
Not quite finished, it'll need drilling and tapping for a grub screw.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0223-05-28_0003.jpg)
That's all I got done today, I couldn't do the morning session due to other things getting in the way. I am going to do my best to make sure nothing else gets in the way as otherwise I definitely won't achieve my goal.
Nick
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Looking good Nick
What sort of engine ,,,,Hot air may be ? sounds like this post will be something to tune into daily :D
Regards Rob
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Almost right Rob!
A few other members will know I've been banging on about making a flame gulper for some time now so this is going to be my attempt! It's going to be based pretty much on Jan Ridders internal valve one just with a few simplifications. I was planning to do a 3D model and draw it up on CAD but that would take some time and I have a good opportunity to get in the workshop this week, so I'm keeping most of his parameters. A few things will need to be altered to accomodate the flywheel and burner though which will save me some time.
For about the first time ever I've actually been and bought some materials for this project, they normally come from off-cuts of scrap I've collected over the years but I thought I don't have much time to mess about.
I went to a local model engineering material supplier - I only found out this place was about 7 miles from me a couple of years ago but have never been. The materials in the first photo cost £12.50 which I thought was reasonable. 3/8" x 3" HE30 alloy, 40mm cast iron, 25mm cast iron, 2mm stainless and 10mm stainless. Just about to order my bearings from Arc Euro Trade, hopefully postal strike won't affect their delivery!
I just hope it works. I managed to make a working stirling engine but I think I'll need to pay more attention to the fits on this one.
Nick
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Hi Nick
Great price on the materials ,,,,,,,must be great to have some were local,,,,,,,,,Jan Ridders has some great designs ,i have a few of his engine plans ,one day i may get round to building one ,,,,i have a flame gulper there a good engine to run ,mine sounds like a 2 stroke motor , i wish you all the best with the build
Regards Rob
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I thought it seemed pretty good, it will be really handy having them just down the road. Here is their website, just incase their prices work out better for anyone, they do deliver and take cards etc. http://www.m-machine-metals.co.uk/index.htm
Yes I like Jan Ridders engines too. I've always been fascinated by flame gulpers so it's been on the list to make one for a long time, hopefully I will be ticking it off shortly!
Thanks Rob, I think I'll need it! :lol:
Nick
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HA HA HA HA HA HA HA HA Darlington , well i never just down there today Nick , pleased you posted link if i get time i think i will call in for a look ,as i am back down there tomorrow ,,,i live in the Newcastle area
Hows the build coming along ?
Regards Rob
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:lol: Small world! I didn't realise but if you do pop in, there is another company opposite that metal place that is a professional model engineers - they do large scale traction engines and the like. You'll need a seat before you see the prices but it might be interesting for a look!
Build is going slowly! Everything on this engine is bigger than I am used to so the metal is taking longer to remove! Also, I keep getting interupted, we bought a new bed at the weekend, but it doesn't fit in the current place in the bedroom so I said I'd move the fitted wardrobe to another wall - I meant eventually, not before the bed is delivered! Wife and parents seemed to have other ideas and the wardrobe has now been ripped out, which means cobbling together laminate floor (where bits are missing underneath it) and the room will need repainting after - stupid bed!
I did get a bit done yesterday though so pics to follow...
Nick
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Nick
When you've got spare time, everyone thinks they are doing you a favore finding you jobs so you don't get board, since I've been retired, my wife find me jobs, my mother in-law finds me jobs, my dad finds me jobs, I keep telling them I'm quite happy and busy in my shop not getting boarded at all do they take the hint NO
Have fun
Stew
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Hey Stew...I got a little project I could use a bit of help on. :poke: :lol:
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Stew! :wave:
Are you any good with bathroom suites? :D
David D
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I'm staying quite
:lol: :lol: :lol: :lol:
Stew
:mmr:
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Yeah point taken Stew! I actually think this could be dad trying to keep himself busy as he's just retired! The wife and I said we were quite happy to leave it for now but as soon as my dad got a whiff of what I was planning he wanted to be involved! Then he said it'd be better to do the work before we got the new bed arrives - otherwise it would never get done, which was exactly my intention! :doh:
Never mind, I'm back out there after I've written this little bit up. I can't even do my write up after the workshop session since we're sleeping in the spare room where the computer is and the wife complains the typing noise keeps her up! :bang: can't win!
Anyway, yesterday I decided to make a start on the cylinder since this is probably one of the more complex parts on this engine.
I started by skimming 1 end of the lump of cast iron to give me somewhere true to grip:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0314-41-26_0001.jpg)
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0314-45-36_0002.jpg)
Turned around in chuck and the OD rough machined down to 0.5mm oversize. All the dimensions for this are metric so am having to do a bit of conversion with the dials. I actually think I prefer metric sizes now, it’s just most of my stuff is imperial. Might adopt the new system! Also centre drilled and drilled straight in with ½” drill (biggest I have) to a bit longer than the required 50mm depth.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0315-37-38_0003.jpg)
Bored the hole out to size. This took a while as I only have a crappy TC tipped boring tool which isn’t very ridid. I have a big boring bar too but I don’ t think it fits in the tool post and is too big for this bore in any case. Finish wasn’t amazing as the tipped tool has a chip out of it but not bad considering.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0315-55-35_0004.jpg)
Decided I would finish turn the OD at this stage, back to a nice slow feed. So why am I getting such a crappy finish now when it was OK before?
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0321-17-02_0005.jpg)
Was just about to start pulling my hair out when I thought I’d re-check centre height:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0321-18-01_0006.jpg)
Only about 3/16” too high! I’d used the same setup plus the bit I used for the boring bar! That could be why! Finish much better now that’s corrected:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0321-21-37_0007.jpg)
Next comes the scary bit – putting the grooves in, only it’s not actually scary anymore on this lathe – at least not on cast iron, brass and aluminium. I am deviating from the drawing here in 2 ways. 1. I just made the grooves the width of my parting tool (happens to be 2.15mm) and calculated how many would fit, and 2. I made them 6mm deep instead of 7mm as I went oversize on the bore by 1mm.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0321-43-56_0008.jpg)
Parting off at about 200rpm under power.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/th__0009.jpg) (http://smg.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/?action=view¤t=_0009.flv)
Finished groove, worked really well.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0321-45-50_0011.jpg)
I was going to stop for a break ½ way through as I thought the tool would be getting red hot, but it wasn’t even warm. The cylinder was luke warm so I just continued. Here it is with all grooves cut and a bit of a de-burr and polish.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0322-28-47_0014.jpg)
Parting off leaving 0.25mm to skim off other end:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0322-37-09_0012.jpg)
Why is it I mess about with all these tools to get a good finish and the best bloody one is the parting tool?!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0322-40-02_0013.jpg)
This picture shows that I only JUST drilled and bored the hole deep enough! Lucky there.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0322-42-25_0015.jpg)
I don’t normally bother lapping the bores on my little steam engine and didn’t on my hot air engine, although I tried to ream that one I didn’t lap or polish the piston. But on this one, I thought I’d better pay more attention to the finish of the bore and pistons if I want it to work. So I chopped a bit off the brush handle and turned it down to a bit under the bore.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0322-58-50_0016.jpg)
Then put a saw cut down the middle and wrapped some wet & dry around it. Medium then fine then fine with oil.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0323-07-43_0017.jpg)
Seemed to work a treat, well happy with the result. Back off into garage now to hopefully finish the cylinder. Didn’t get my morning session in due to stupid bedroom!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0323-18-50_0018.jpg)
So far I am trying to pay more attention to detail on this project, and I am using known materials. Hopefully, if I can keep this up it will turn out to be my best one yet. I just hope it will work, fingers crossed!
Nick
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Looking good Nick
:thumbup:
Stew
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Nice machining (if you forget the dodgy bit :lol:)
Don't forge to post later ...... :coffee:
Tip, there is always the sofa .... ::)
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So, I'd done what I thought was the hard bits on the cylinder so I clamped it in the vice on the milling machine and started machining the flat for the intake port. I used a brand new cutter to give me a good finish and it was going well:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0422-03-23_0001.jpg)
So far I am trying to pay more attention to detail on this project, and I am using known materials.
:doh: :bang: :(
That must have been tempting fate!
This happened:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0422-19-35_0002.jpg)
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0422-21-11_0003.jpg)
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0422-21-37_0004.jpg)
This was caused by the vice not being tight. I'd got down to my 7mm depth 1 cutter wide and I thought instead of doing all that again it would be easier to control if I now used the side of the cutter to cut where I wanted to in the Y direction. As soon as I tried this the thing slipped and dug in. The vice felt nice and tight, the only thing I can think is it was it was at it’s extreme of opening so I didn’t have much thread engagement and it wasn’t actually tightening, just causing damage to the thread. Will have to strip the vice down to find this out.
So the rescue mission started with taking the jaws off the vice and clamping, this time it did tighten and I was able to half-save it. The wall is a little thinner than it should be and there is still a fair of a divet out of it so am a bit gutted, but it should still function.
All I did after this was cut the port, which actually turned out slightly bigger than the 3mm it should have been. I guess I shouldn’t have used a 3mm end mill! Or maybe I could have got away with it if I hadn’t drilled a hole at each end first. I will need to make sure there is enough meat on the valve to let it close fully but it should be easy to adjust.
Cutting the port.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0423-38-02_0005.jpg)
How it looks now.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0423-49-50_0006.jpg)
Still a bit of work to do on this - Two small flats need milling for the pillars, then drilling and tapping. Then drill the long hole drilling 4mm and turn up bronze bushes for each end.
There’s no point trying to rush this, it’s definitely not going to be finished by the end of the week and if I do, other errors are likely to happen! Realistically, the end of next week is now the aim but I’m not going to get myself beat up about it, if it doesn’t happen –tough!
Nick
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Nice rescue Nick, its always a bummer when something like that happens, you may be able to hide the divot later on in the build with a bit of bling shiney brass bit.
Have fun
Stew
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Nick,
From that one picture it looks like you were "climb" cutting. That would be one reason that happened to you.
Nice save on the part by the way.
Bernd
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Bernd,
I was climb milling as I thought it'd see if it gave a better finish so that is why it got dragged out then and not before, it was only the tiniest of cuts though. It was when I tried setting it up to attempt to save it when I found the vice wasn't clamping properly - not sure what's happened there. Will need to investigate, it clamped up fine when I removed both jaws though.
Stew, I never thought of that. I might be able to bolt a brass plate over the top or something if it works!
Hopefully I'll be able to finish the cylinder tonight and put this mishap behind me!
Nick
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Nick,
Some things I have found with climb milling..
You must have no backlash in the leadscrew/nut. Otherwise the milling will seem to be going fine and then suddenly the table jumps to take up the backlash.
This forces the cutter to dig into the work further pulling the table quite violently. At the same time the cutter tries to drag itself out of the collet holder forcing it deeper into the work.
Something has to give, either the work which can be dug into, or it get ripped out of the vice and across the room.
Or the cutter snaps, again usually causing more damage to the work.
Some machines are designed for climb milling, such as my Beaver, by having two sets of feedscrew nuts to totally eliminate backlash. Unless you have these then climb milling is always going to be a disaster waiting to happen.
Proven several times on my Sealey milling machine :(
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Nice going Nick, you'll get over the minor divot I'm sure :thumbup:
Why is it I mess about with all these tools to get a good finish and the best bloody one is the parting tool?!
You've already answered that one Nick :poke:
Good thread, looking forward to more. :clap:
CC
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Nick,
Don't worry about covering up the blunder, the wick will take care of that, besides, after a few runs the area will be filthy black anyway.
The only thing to really worry about is if going slightly deeper has changed any of the running or starting characteristics. They are a pig to start at the best of times, until you find the sweet spot for the flame.
I couldn't get mine to run at all with Jan's angled wick design, and came up with my own fixed position vertical one, which gives much better running and starting. In fact when I told and showed Jan about it, he incorporated it into his latest twin cylinder design, which runs very well.
The most critical part on this engine is what you should be coming to soon.
Make sure you have the barrel bore and piston perfectly smooth, parallel and lapped together. The piston shouldn't drop down the cylinder, but gently slide it's way down under it's own weight. There will be no lubrication used in the bore at all, the two parts are designed to be self lubricating, by using the carbon content in the cast iron of each one. Oil will stop it dead, and it won't restart until you have cleaned every trace out with spirits.
John
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John,
Good point, probably won't be able to see the blunder.
Thanks for the advice on the piston / valve. I think this could be the bit I struggle on. I noticed that Jan changed his design after yours and did a bit of a study to show the best place for the wick. He seems to think it is vertical and right behind the port, seems strange but am sure I will have to try many positions.
Might tackle the piston tonight, I still need to make the small bushes for the cylinder too.
Nick
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Actually Nick, it was myself that gave Jan the original settings for the wick, but mine were based on 1/4" (6.4mm) not the 8mm he has ended up with. I found that the 1/4" gave the best all round performance, and I experimented with both larger and smaller. Without the vertical wick, as soon as you try to move the engine, it will stop dead. With the vertical wick, I can actually carry the engine around and even run it outside, a thing that Jan marvelled over, as before that, it was almost impossible. That has to do with the position of cold air pockets around the inlet hole. Getting too technical now, so I will leave you to it.
I am sure that you will get it sorted.
A little bit of advice you won't find on Jan's plans, wash out the ballraces with spirits to get rid of the grease and put only a tiny amount of thin oil in them. The friction reduces dramatically and will really help when you come to get it running.
John
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Darren, good point there about climb milling. I’ve managed it in the past but maybe it was the softer materials that allowed me to do that. I am going to avoid it like the plague in future now!
Good tip there John, thanks. I received my ball races from Arc Euro yesteday and although I obviously haven't tried them properly, there did seem to be a bit more drag than the ones I used on my hot air engine, but they felt smoother at the same time.
Right, will post last night’s progress. This was basically finishing off the cylinder, that is, milling the two flats + drilling and tapping for the pillars and drilling the long hole for the valve rod.
Setting up perpendicular to the port face to mill flats:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0522-14-46_0001.jpg)
Flats milled – nearly took 2mm off but thought it look enough when I got to just under 1, so checked the drawing again and it was infact a 1!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0522-24-45_0002.jpg)
Holes centre drilled:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0522-54-11_0003.jpg)
Opening up to tapping size – changed this to 2BA which was nearest I had to 4mm:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0523-05-12_0004.jpg)
Tapping – was thinking of doing this under power but leaving it not too tight in the collet so it would slip. Chickened out though and turned the spindle by hand! I was always taught to go 1 turn forward ½ turn back anyway.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0523-14-20_0005.jpg)
Set up to centre drill and drill the long hole. I used the square just as a check that it was clamped correctly.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0523-47-53_0006.jpg)
It worked really well with the 4mm drill, didn’t seem to wonder off at all, it’s come out spot on.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0600-00-20_0007.jpg)
The only thing was, there was something funny happening with my milling machine when drilling that long hole. It felt like something was binding, either the spindle or gears the further down I went on the travel. Will have to look into that, I know the guy that bought the same one at our club has had trouble with his so will have to investigate.
Right off to attempt the piston / valve now I think!
Thanks to all for your interest, support and advice. :bow:
Nick
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Good work on the cyl Nick
Watching with interest
Gerhard
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This instalment covers the pistons, or piston and valve.
I started off in the same way as the cylinder and trued up the cast iron:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0621-33-27_0001.jpg)
Turned it around in chuck and started whittling it away nearly down to size:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0621-47-08_0002.jpg)
Now taking finishing cuts of 0.0005” and trying in cylinder:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0621-54-59_0003.jpg)
I got so far and thought right, it’s time to start lapping. I just did that with some wet & dry wrapped around a bit of square tool steel.
But it still didn’t fit after lapping so I took another ½ thou cut off and it slid in – DOH! It was a good surface finish so need minimal lapping and I didn’t want to reduce the size any further.
Also turned the spigot:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0622-24-25_0004.jpg)
Parted off:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0622-47-18_0005.jpg)
Am not that confident it’s a good enough fit, feels a bit loose so am thinking I’m probably going to have to re-make it.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0622-52-16_0009.jpg)
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0622-53-04_0010.jpg)
Here’s a video of the piston sliding down with the cylinder resting on the surface plate, trouble is, the surface plate isn’t that flat so air will leak around the cylinder. If I put my thumb in the end and form a tight seal the piston stays pretty much where it is until I remove my thumb. So it might work, I’ll give it a try but I’ll know the first place to look if it doesn’t!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/th__0006.jpg) (http://smg.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/?action=view¤t=_0006.flv)
I also made the valve for the back end of the cylinder. I thought with this one I won’t make the same mistake twice, I’ll measure the bore and aim for maybe 0.1mm over then lap the rest until it fits nicely. Only got down to 0.1mm oversize, it wasn’t – it slid in again so I had to do minimal lapping to avoid making it much smaller. I have about the same fit on both pieces now.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-0623-47-46_0008.jpg)
Just need to drill the cross hole in the valve for the valve rod (slightly different design to Jan’s, I just incorporated it into 1 turned bit). Interestingly, Jan calls for a 2.3mm hole with 2mm rod. Wonder if this somewhat sloppy fit is just to stop things binding?
On the piston, I am going to do it the same way as my hot air engine. Mill a slot into the cast iron and cross drill right through. The pin will be a nice sliding fit in the cross-hole but a tight fit in the rod, thus will be held in the middle to prevent scoring of the cylinder walls.
So I’ll finish those off, make the little bushes, valve rod, adjuster and pillars then that’s the cylinder and pistons complete. Still have the base plate, crankshaft, conrod and bearings to do. Who was I trying to kid doing this in a week?!
Nick
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Nick,
That 2.3 mm hole is necessary, it allows for the transition going in and out and stops vibration from the rod affecting it.
John
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Thanks, thought he must have specified that for a reason!
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Due to the bedroom obstacle and a cold starting on Sunday the only thing I've managed to do on this was 1/2 a cylinder pillar ... wasn't even worth taking a pic of. Just realised I'm taking lots of pics of straightforward turning which is pretty pointless after the first one! I am machining these from 303 or 304 stainless (can't remember which the guy said, but it is free cutting which ever that is!) It machines really nicely and leaves a superb finish.
The good news is, the bedroom should be finished by Friday and my cold should have eased off so I should be able to restart this project.
Have been thinking about what I need to do and wondered if it's worth getting a length of 6mm silver steel for the crankshaft and 3mm for the crankpin because it's usually a nice ground finish. got a couple of questions on this though
a. Will 6mm rod be a good fit in the bearings? I would have thought if size for size I'd have a job getting it through!
b. does silver steel silver solder ok or would I be best going for mild.
Nick
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I was always taught to go 1 turn forward ½ turn back anyway.
You and me both Nick ............. and I suspect ½ the collective at least :dremel:
CC
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Hi all,
I've finally found some motivation to pick this project back up. The week I had on leave was ruined by the bedroom redesign and at the end of that weekend we all caught some sort of cold but this wouldn't shift. Still got remains of it now nearly 2 weeks later which is pretty rare for me. I tried a couple of times to go into the workshop but I simply didn't have the energy. Anyway, tonight I felt full of life and enthusiasm which was good!
Tonight's job was the two cylinder pillars, I'd already made a start on one but didn't take any pics of the machining, it was straight forward turning, the critical dimension from the base to the thread shoulder. As long as it's high enough to give the flywheel clearance, they are both the same and I make the bearing blocks the corresponding height that is all that matters. Also getting the thread straight was critical.
Here's one of them.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2100-02-57_0002.jpg)
The one thing I am doing is getting better at forward planning with the more experience I get. At one time I wouldn't have put undercuts on and chamfer on the end of thread then I'd wonder why it wouldn't screw all the way home. I tried to part this stainless off but didn't like the noises coming from it so chickened out and sawed them off, turned them around and faced to length. For the undercut I used a hacksaw as again, the thin grooving tool was having none of it. I think I'd ground it from a bit of duff HSS that I had overheated at some stage by grinding too hard as it was all blue / brown colour.
Pretty chuffed with the result, everything looks very square.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2100-08-37_0003.jpg)
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2100-09-04_0005.jpg)
This meant I had time to turn the bushes for the valve rod. Luckily I found some bronze (I think) off some old balance scales which was almost the right size. Carefully turned it down to size and drilled it.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2100-05-34_0007.jpg)
My valve rod is actually 3/32" not 2mm so just got the nearest oversize number drill and it gives a nice sliding fit.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2100-07-25_0001.jpg)
Here they are assembled, rod was marginally tight at first but a few strokes up and down and it’s a lovely sliding fit now, drops through but doesn’t wobble.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2100-14-17_0008.jpg)
I may need to loctite these in as it was more of a push fit than a tight press fit.
Am very impressed the way this has gone so far. Apart from my blunder on the cylinder, it’s gone very well so I am just waiting for something bad to happen! The pistons may not be a good enough fit yet though but they are fairly simple to remake if need be.
Next on the list is the valve rod, drill the hole in the valve and the rod control at the other end.
Then finish the piston off, bearings, conrod, crank and base!
Still a long way to go, I don’t know why I am so optimistic with timings when I start out, you’d think I would know by now!
Nick
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You're going about it the right way Nick.
If it ain't critical, use what you have to hand.
I have seen people searching for weeks to find exactly what is needed for a build, and all they had to do is look in their bitsa box for something close enough.
The only reason a lot of certain sizes are used on plans is that is what the designer had to hand when he built it. If he had found something different, he would have used that.
At least you can now say it isn't built exactly to plan, you modified them to suit your own ideas.
John
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Going well Nick that looks a nice finish on the cast iron cylinder.
You probably know but there is more than one way to get the screw down onto the the shoulder, you can use a washer or you can slightly countersink the female thread.
Have fun
Stew
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John,
I think I remember the guy asking now if 3/32" would be ok! I actually bought most of the materials for this project - first time ever to save routing around and hacking big chunks out of unknown stuff. It's paid off so far as the material I have bought cuts superbly. The bitsa box is still required though, I normally get everything from there! Like you say though, it'd be as easy for people to just slightly adapt things to suit what is easily available - crazy searching for ages!
There are only a few minor differences in my design but mainly to suit the flywheel, because of its large diameter the con rod will need to be longer. Anything else is just simplified, if Jan has 2 steps on something, I only have the 1 that is required! I will have 1 piece bearing blocks too. Hopefully it won't detract from the appearance too much, don't think it will.
Stew, the cast iron seems to be a nice bit of material, gives a very smooth finish then a bit of wet & dry gives a nice shine to it. Good point, I might try the counterskink way next time, might be easier in a lot of circumstances.
Thanks for your interest guys.
Nick
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Just a note Nick, if you haven't already made the little striker adjuster that is on the end of that rod you have shown. The original is a real PITA to adjust and keep tight.
If you want a piccy of mine that I used, and it works great, let me know.
John
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John,
Would like to see your version as I was going to redesign it anyway, it looks a pita to be honest. I was thinking of a couple of ideas but actually, if you say it's hard to keep tight I guess the pinch screw needs to go. The end of the rod could be threaded with a nut either side and maybe a fixed striker?
Nick
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Nick,
It isn't greatly redesigned, but it does make it dead easy to adjust.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/flameadjust.jpg)
I put a small flat on the rod that runs thru the cylinder fins just where this bit mounts. You can just use a round bar, it doesn't have to be hex. The screws are 2mm.
This adjustment, together with the flame, is very critical. I found that Jan's way kept coming loose, as it was difficult to get in to adjust and tighten everything up afterwards.
This engine does need a rebuild and bling up. This was the prototype to get two of the engines you are making running together. Rather than running on spirits, as this one does, I have the plans for a micro bunsen burner that runs on gas, but like everything else, I need to make the very high speed drill first, so that I can drill the very small holes required for the burner jets.
Then this engine will be completed to how I first envisioned it.
John
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John,
Thanks for that, the engine looks great. Actually, I had already put a bit of square brass (run out of brass hex but have some steel) to one side to do exactly as you have done (great minds think alike!). I would have forgotten to put a flat on the rod though which would make it difficult to tighten. I couldn't understand why Jan did it the way he did, then I thought the brass might be too heavy and cause the rod to rotate and put unnecessary pressure on the valve, obviously it doesn't have any effect.
Thanks, I will follow your method there then. With this type of engine, it's nice to use methods you know work as trouble shooting should be easier at the end.
Nick
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Nick,
I made two of these engines at the same time, and even the pistons and cylinders were interchangeable, and still are, after many hours of running. I first got one running, then using the exact settings, even down to flame position and height from the first, the second was up and running in no time.
It is a pain getting that first setting, but I don't think you will have too much trouble if you do your tweaking logically, rather than thru frustration (and it will get frustrating), trying things willy nilly.
John
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John,
Thanks, I will need all the advice I can get with this one it seems! I think when it's done, if it runs, flame gulpers should be out of my system for good!
:offtopic: My list of projects has shrunk... I wanted to do an i.c. engine and a hit & miss air engine to chuck's design and an i.c. hit & miss - but then I thought last night, hang on, why don't I just do a proper hit & miss and that will get the lot out of my system!
As with this one, as long as I take a methodical approach, proven design parameters and advice of others that have already been there and done that, I should be ok.
Couple more questions if I may:
Is your con rod 1/8" brass?
I have found some 1/8" brass that looks flat enough so I was planning on using that. Not sure how it'll machine though. I think Jan's version looks a bit thin. My bearings are also slightly different. 12mm OD, 6mm ID for the mains and 7mm OD, 3mm ID for the big end. I bought 2 sets from arc euro so I can use them on my I.C. engine one day!
Do you think it is necessary to balance the crank?
I was planning on not doing, it's something I can do afterwards but if it's critical I may as well do it to start with.
What does your big end look like? Can I see your big end? Could you post a picture of your big end up? :lol: Having trouble wording this one ... Is your crank pin / retaining screw to the original design? I am thinking of simplifying this. On my hot air engine, I just allowed the bearing to slide on the rod and take up it's natural position instead of being restrained, as long as the crank pin is long enough it can't really come off unless the rod got severly bent!
Nick
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Nick,
I think we discussed this the other day, buying specialist bits in to make something when almost anything will do.
This engine produces fly power, so if you could stop a sheet of paper from bending, that would do for the conrod, I just used what I had knocking about, as long as you can get the bearing to fit almost anything will do.
With reference to balancing, this engine is a very slow runner, I just made a basic shaped crankweb and I had no balancing problems.
Not sure how it'll machine though
This is where a file and handpower springs to mind. As long as the holes are the correct distance apart, it could be made to any shape. Two washers with a bit of rod soldered between would even do it.
LET GO OF THE PLANS SPECIFICATIONS AND USE WHAT YOU HAVE ALREADY GOT.
I will see if I can get some piccies taken this evening.
John
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Nick,
I have got you some pics, I hope these will explain things a little better. As said before, please excuse the state of the engine.
I will just explain a little about the big end area. It really needs to have a rigid fixing of some sort as if it is floating, it is liable to cause friction by being out of line at times. Even a tiny amount of the wrong type of friction will stop the engine running. These six shots show it from all angles, but you could use the same sort of setup, just with one crank. You do need to be able to disassemble fairly often, as muck will again cause too much drag and prevent running. So I just used a little finger screw to get things apart quickly.
The crank web was just a minor attempt to balance out the weight of the finger screw.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/lick01.jpg)
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/lick02.jpg)
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/lick03.jpg)
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/lick06.jpg)
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/lick07.jpg)
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/lick08.jpg)
These last two shots show the position of the wick. It is exactly the same on the other cylinder. I use fibre glass strand wick which doesn't burn away like normal cotton stuff. I adjust for best running by pushing the bit of wick sticking out slightly one way or the other. This position gets me started after a warm up of the cylinders, then I tweak the wicks once it has a minute or two to warm itself up.
You will also notice how much muck the burning meths produces, imagine that inside the cylinders. That is why I strip down and clean out with meths every couple of hours running.
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/lick04.jpg)
(http://i202.photobucket.com/albums/aa102/bogstandard_photos/lick05.jpg)
I hope this helps.
John
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John,
Thanks very much for your time and effort taking the photos, they are very helpful. I might have a think about the valve rod too, I am worried bending it I may bend the straight bit, yours looks silver soldered, not confident I'd get it perpendicular by that method though.
Tonight I made the effort to get a little bit done. I am travelling down to south wales tomorrow, it's going to be a long day, up at 4:30am to get an early flight, I'll be back about 9pm and don't think I'll be up for the workshop - besides, it would actually be dangerous.
As discussed with Bogs, I had pretty much the same idea as him although I've followed his as it was even easier to make from hex bar.
No machining to show as it was very straightforward. I took a bit of hex bar, faced down to length in the lathe. Drilled and tapped a 6ba thread in one end about 5mm deep, enough to break into the cross hole for the rod. Then into the milling machine to cross drill the rod hole and drill and tap the striker hole 6ba.
Here are the parts including a long 6ba bolt (striker), lock nut and a short 6ba bolt to clamp it onto the rod:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2322-28-39_0005.jpg)
Here it is assembled, need to make the rod next!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2322-31-03_0006.jpg)
I am still crap at taking photos, these were inside, it just wouldn't work with the flash, tried on a couple of surfaces. Am guessing the blue bedsheets were too dark and the white paper too bright :lol:
Am getting there, if a little slowly!
Nick
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Well,
a tiny bit more done on this. I decided to bend the valve rod into that daft shape. I can see why it was done like that, I just don't like bending things though! Anyway, I fannied on for about an hour or so with this but it produced a decent result:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2623-07-58_0001.jpg)
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2623-10-06_0003.jpg)
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2623-11-49_0006.jpg)
I drilled the cross hole in the piston about 0.2mm oversize and the rod length was a few mm longer I think because of the hex striker block. Anyway, it's not critical, I know it's ok at the 2 extremes, the adjustment can be done with the bolt and the pinch bolt. It's a nice smooth sliding fit, hardly any friction there so looking good at the mo.
I also got the bearings hacksawed out and marked so starting on those tomorrow night.
Nick
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Nick,
As you know, mine was made to the old drawings, which showed a silver soldered right angle. I just held the two parts in the correct position with a couple of small magnets about 1/2" from the joint and soldered it up.
Yours looks just fine.
Once I had the engine up and running, I filed off the rod very close to the adjuster, so it is dead easy to set up in the same position after stripdown.
John
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John,
Yeah I was going to try the right angle but I only have a cheapo pencil torch in my garage at the moment so I thought I wouldn't be able to silver solder - sometimes it doesn't even give the right flame, spits a big long flame out of the end with no heat! However, as the rod is only thin I think it might have done the trick as I did manage to get it to cherry red a couple of times to bend it.
I just kept tweaking it to get it as square as I could. I was worried about putting a bend in the long straight bit but there is no binding so should be OK.
Ah, good point, I can fine tune that length if it runs!
Nick
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Hi all, hope everyody is well.
I got a bit more done last night, but didn't all go to plan - you'll see below! I was planning to get another bit done tonight but for some reason my 3 1/2 year old son has only just gone to bed, the wife went ages agio and left me with him! Normally he's asleep by about 19:30 and it's 22:55 now!
I wanted to get the bearing housings done, these were to be done from aluminum plate. Again, I am simplifying Jan’s design slightly. Mine will have no support pillars and are a simple rectangular shape to save time.
Started by marking out the outline – something I have rarely done before, even used marking blue!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2720-56-39_0001.jpg)
I was planning to cut the flat bottomed recess for the ball races with a 12mm end mill. But then I remembered when I tried that on the hot air engine, the hole it produced was much bigger than the bearing! That was in my old mill, with old cutters though. Nevertheless I decided to do a test run on a bit of scrap:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2721-06-19_0002.jpg)
You can see that the hole produced is quite a bit too big, a very loose fit. So I set about measuring other end mills I had to see if one was just undersize – there was one, but I tried that and it was no good – too small!
So I found a drill that was just a little undersize, 15/32” I think ~11.91mm. I ground it flat and put a couple of reliefs on it, did the test and it seemed to cut ok so I would go with this. The fit on the bearings was a press fit.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2721-20-09_0002.jpg)
Back to the job in hand shaping the housings then:
Milling to width:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2721-35-08_0003.jpg)
Put them together to ensure both the same width:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2721-52-58_0004.jpg)
They ended up 0.1mm under the 30mm I decided on but it really doesn’t matter! Being the same size is more critical.
Took a skim off the bottom face of both at same time – are end mills meant to be used like this? It doesn’t seem give the best or flattest finish.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2721-58-17_0005.jpg)
Started milling the other end to length but I didn’t like using the side of the cutter like this:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2722-06-31_0006.jpg)
There was a few mm to take off so I sawed the excess off first:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2722-07-35_0007.jpg)
Then milled both at once like this to ensure both the same length / height:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2722-12-57_0008.jpg)
I liked this marking out lark, it was easy to see things and because the arrangement of holes I’d decided on made it easy to confuse the two ends I decided to mark it out properly – ish!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2722-33-48_0009.jpg)
I then spend a good quarter of an hour decided what was the best procedure for drilling all the holes – there were to be 2 x 6mm holes (just to make it not quite so boring), the 6.5mm hole behind the bearing to clear the 6mm crankshaft, the 12mm flat bottomed recess, and another 12mm decorative hole.
First off I decided I’d just make all the holes 6.5mm to save swapping drills. Then I decided I could have drilled half the holes by now if I’d just started!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2722-46-37_0010.jpg)
The recess – looks not too bad considering it’s a bodged drill!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2722-55-04_0011.jpg)
Finishing off with radiused corners – I nearly always mess the part up doing this, it always seems to move in the vice. I should take little cuts instead of trying to plunge in 1 go. So I had to take another couple of finer cuts so it won’t be quite to drawing but I came up with a method of getting them all the same using a parallel across the end of the vice jaws and flipping it over for the other edge. I’m not even convinced it looks that good, it seems to have become one of my little ‘trade marks’! It just makes it a bit more pleasing on the eye … I think?!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2723-11-43_0012.jpg)
Jus the holes to drill and tap in the bottom. I’m using 2ba. Again, I just marked them out and this time centre drilled then drilled.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2723-58-32_0013.jpg)
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2800-03-07_0014.jpg)
Finishing off the tapping in the vice once the taper tap had started the thread sufficiently:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2800-29-55_0015.jpg)
I polished them on some wet and dry to try to get some of the nasty marks out. I hate polishing though so any I do is minimal. On the 2nd one I remembered that somebody recommended using white spirit as a cutting fluid on Aluminum – so I tried it for tapping. Worked pretty well, so I did a final quick polish with some white and wire wool! It was to clean them more than anything – there’s little point in putting actual polish on it unless all the machine marks are gone now in my opinion and they aren’t. I have ‘polished’ all the other items on the engine just with oil and wet & dry so far, gives a nice sort of engineering brushed type finish.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-2801-11-34_0016.jpg)
So, was quite happy with those, then I pressed the bearing in with the vice, but the press fit must have been too tight and it made the bearing bind up. Luckily when I got the bearing back out it sprang back to shape and is free again but I have probably done some damage to it. So I need to open up the recesses some how so the bearings are a nice sliding or push fit. I kind of knew this, I just assumed a press fit would be ok but I guess due to the small size of these it just compressed the outer ring.
I have thought of a couple of ways of doing this. Either chuck in 4 jaw in lathe and set it running true, then make a small boring tool from an old drill and bore out marginally. The trouble will be clocking it, I don’t have a dti with the little probe that flicks out sideways. Could put something good fitting in the hole and clock it that way.
Another thing I thought of was making a tiny cutter with a grub screw and bit of HSS for the milling machine.
Or, I might get away with using the 12mm end mill in the lathe once clocked in 4jaw or even just hold the cutter in the vice and twist it by hand for the amount that needs to come out. I’m guessing it’s the run out on the cutter that makes it cut larger.
Should be able to save them some how though as the holes are too small at the mo. Any other ideas?
Nick
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Looking good Nick, you can use a milling cutter held in your toolpost for boring.
Maybe a two flute if you have one?
-
Nick
Good progress, have you got a boring head you could set the job up in the mill and bore it out with that.
I've got one of those little clock round the corner things you can have, I'll try and get it to you next week through RO internal mail.
Cheers
Stew
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Darren, never thought of that!
Stew, unfortunately I don't have a boring head. Is one of the things on my list!
That's really kind Stew, would be really useful.
Cheers,
Nick
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I can fine tune that length if it runs!
And what does that mean Nick!!!!!
You have no reason to think failure, IT WILL RUN, we will not allow to not run. :poke: :wack:
Just a little note about some of your holding techniques. You have been very lucky in some of your machining.
When you are cutting two or more pieces, say side by side or on top of each other like for your end milling, the thickness or width of the two parts can cause one to be held tighter than the other, it only requires a minute amount of difference between the two for one to be sent flying out of the vice or move and have the cutter bury itself into the job.
If you can, stick them together some way (I use superglue or good quality double sided tape) or drill holes in areas you are later going to machine away, and bolt them together.
I don't know why people get such a rough finish when using an end mill. So here is how I do it, and it gives me mirror like results.
You really need a new or little used cutter for doing this job, one that has been used a fair amount will have dull side flutes. Or use an area of the cutter towards the shank, that is liable to be the sharpest.
Get the cutter speed well up with a very slow feed, and keep away from climb milling if you can, plenty of lube (for ali, a squirt of WD40) and if you have an air blower, keep the shavings from being dragged around by the cutter and so getting embedded into the cut face (DON'T use a brush, it is liable to get snatched into the cut). The finishing cut should only be something like 0.002" (0.05mm).
John
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I don't know why people get such a rough finish when using an end mill. So here is how I do it, and it gives me mirror like results.
You really need a new or little used cutter for doing this job, one that has been used a fair amount will have dull side flutes. Or use an area of the cutter towards the shank, that is liable to be the sharpest.
Get the cutter speed well up with a very slow feed, and keep away from climb milling if you can, plenty of lube (for ali, a squirt of WD40) and if you have an air blower, keep the shavings from being dragged around by the cutter and so getting embedded into the cut face (DON'T use a brush, it is liable to get snatched into the cut). The finishing cut should only be something like 0.002" (0.05mm).
I concur with all of that; in particular the sharpness of the cutter has a particularly marked effect on the final finish. I have one truly excellent end mill which I reserve for these final cuts.
One thing, and maybe it's because I have a big heavy mill, I find I can get away with a 0.002" climbing cut, which is a little smoother than the equivalent conventional cut.
-
Bogs,
Thanks for the tips. I did use a new cutter but guessed on the speed and didn't use any lube. I used a 12mm cutter with the max in the lower gear which is meant to be 1000rpm.
I'm not sure whether I mentioned in the text but you're right, I was lucky. When I took the skim off the base with both clamped 1 on top of the other, it was only a tiny skim to make sure it was square after cutting the sides. but when I tried to do the same on the other end taking the bigger cuts to get down to size, as you pointed out, 1 of them kept moving. It must be a minute amount as you said because I'd previously milled them together to make sure they were exactly the same size.
Probably the only reason I got away with it when I turned them around was because I hadn't touched the thickness. Will certainly remember this in future.
On my rocking engine when I used that poor quality aluminium from the shelf it gave really bad pick up, sort of tearing the soft metal and I did have to take a small climb cut to get an acceptable finish. I will try the lube, still not sure whether the speed is right. Also, they were cheapo end mills from China - £12 for a set of 7!
Nick
-
Here is tonight’s instalment. It’s quite hard to get motivated to get out there initially after being at work all day but once I get out there I don’t want to come back in! Came in at about 11:20 tonight, got a reasonable bit done.
First I thought I’d measure the 12mm end mill to see if it was actually a 12mm – it was! So I decided to put it in the vice and try opening the bearing housings by hand:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-3020-45-42_0001.jpg)
To my surprise it worked a treat – nice push fit:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-3020-42-05_0002.jpg)
I decided to put a dab of loctite on them; they will never be coming back out.
So with that bit quickly done, I was feeling quite good and made a start on the crankshaft. I decided I would do it my old way, but with more care and attention – threaded shaft, disc and pin.
Started by facing off the stock (think this is either 32mm stainless or some sort of chromium steel I was given at work) it seems to machine quite nicely whatever it is. I then drilled and tapped 3/16” x 40 tpi.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-3021-09-27_0003.jpg)
I didn’t fancy my chances of parting off – am a bit nervous about doing steel for some reason, it starts to make squeaking noises then I get the hacksaw out! Anyway, it was sticking way to far out of the chuck for parting off. Getting it closer to the chuck would have meant another saw cut since it didn't fit through the chuck body. So this time I just skipped a step and went for the hacksaw – which is now pretty blunt!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-3021-25-40_0004.jpg)
About 10 mins later I had this:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-3021-32-43_0005.jpg)
I was pretty happy with that straight cut and the finish was ok, so I thought I’d just leave it!
Lol, just checking you’re awake, of course it would be screwed to the shaft and faced off later!
Started machining down some 10mm stainless for the shaft.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-3021-42-44_0007.jpg)
It cuts really nicely, think it’s 303 or 304. The metal comes of in long spirals:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-3021-42-34_0006.jpg)
In fact on one of the cuts it was one continuous piece of swarf
Taking finishing cuts and lots of passes at the same setting. I had a bit of a flexing issue so the end furthest from the chuck was always larger – this makes it hard to test fit in the bearings. Consequently it is a marginally looser fit on the end near the chuck that I would have liked, no play but just a sliding fit rather than a push fit. I contemplated buying some 6mm bar but I think it would have needed reducing marginally to fit the bearings anyway.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-3022-23-35_0009.jpg)
I turned the shoulder for the thread and gave it an undercut with the hack saw – dodgy I know but a parting tool wouldn’t work that far out from the chuck.
Then I put the 3/16” x 40 Tpi thread on. This engine is a bit mix & match on the sizes. It was originally designed in metric so for the first time I am trying to stick to that, but all my taps and dies are imperial or BA and some of my metal was imperial! Oh, and my machines, so there’s been a bit of conversion going on! I used to always use imperial but I think I actually prefer metric now – if I had DRO’s I definitely would.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-3022-34-19_0010.jpg)
Crankdisc screwed on and loctited in place.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-3022-55-44_0011.jpg)
Facing disc down to thickness. This also gets it square to the shaft if there is any misalignment in the threads. The back face doesn’t matter as long as it doesn’t catch on anything but there doesn’t appear to be much misalignment anyway.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-3023-01-59_0012.jpg)
Bit of a polish with some wet & dry and here is the crankshaft / disc.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-3023-17-07_0013.jpg)
Next I turned the crankpin which is 3mm. I decided to use some 1/8” silver steel for this, it didn’t need to be silver steel, just about anything would do, it was just the nearest size I had.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-3023-40-06_0015.jpg)
Turned the slightly smaller shoulder and threaded 6ba, don’t think I took a photo of that.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-3023-49-04_0016.jpg)
I set the crankshaft / disc up in the milling machine to drill & tap the hole for the crank pin. To do this I just aligned the centre drill by eye to the centre pip then wound the table out 13.5mm which is the throw.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-11-3023-52-11_0017.jpg)
Centre drilled, then drilled and tapped 6ba. Screwed and loctited the pin in place:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0100-12-56_0018.jpg)
Some of you will notice I’ve deviated from the drawings here. I’ve just got a pin sticking out rather than a special shoulder and screw that clamps together. The cylinder / bearing housings will be arranged on the baseplate such that the big end bearing is positioned in the centre of the crank pin (1.5mm space either side) but it is free to slide which should allow it to account for any out of squareness without binding. As John (Bogs) said it would be better practice to do it the way he has and Jan has in his drawings but this is the same method I used on my stirling engine and it seemed to work on that so I’ll give it a go here. If not, I can easily make up a spacer and a screw to make it rigid. Then I'll get :poke: and :wack:
I'm also not bothering with any balancing. I think the pin / big end is light enough and the flywheel sufficiently heavy not to make a difference on this design.
Quick test assembly:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0100-15-11_0019.jpg)
I still need to machine the slot and hole in the piston, make the conrod, make the base plate, a base from brown stuff and now I think a burner. I was planning to use the glass burner from my chemistry set I had when I was about 10 but it’s a sort of bulb shape and interferes with the cylinder columns so I don’t think I will be able to manoeuvre the flame into the correct position with that one. Not sure whether to solder a burner or machine one from solid alloy as I did with my stirling. This will need a lot more fuel though so think I may solder it to save time boring stuff out!
Got one eye on the finishing line but am determined not to attempt any start up until it’s completely finished!
Nick
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Very nice Nick, very nice ..... looks like a bit of mill finish steel .... get yourself a magnet to test Stainless. Though you will be able to "see" it in time as it has it's own look colour usually.
Also it's the one with no rust on it after you've had it for a while :lol:
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Thanks Darren. What is mill steel? Or did you mean mild? Pretty certain it's not mild, the OD has a very shiny mirror, chrome like finish and there's no rust in sight. It reminds me of a bit of Chromium steel which came as a part of Sparey 0.8cc diesel kit from Woking precision models (incidentally that was the first thing I attempted to make as a first project - didn't get very far!!). Will try it with a magnet though.
Nick
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Strew brought me over some mill steel when he came for a vist.
He informed me it's mild steel that has had it's outer diameter mill peeled which gives it that distinctive banded finish.
If it was chrome steel you would prob have a very hard time cutting it I would guess.
Some SS is magnetic, but no where as near as much as normal steel ... so don't let it trick you :thumbup:
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Ah right. It does have a banded finish. Thanks for the info.
I didn't really have any problem cutting the other chrome steel though, it was a little hard, a bit like silver steel, comes off in small chips.
Well I'll be happy if it doesn't rust cos I can't be @rsed polishing it! :lol: That's why I thought I'd try to use stainless wherever possible on this build. Should have used it for the bearing housings too but not sure how it mills, not tried it on mill yet.
Nick
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SS on the mill .... turn the spindle rpm down, try half of what you would use for MS. Then adjust as you see fit.
Go at it too fast and you'll wear the teeth right off your cutter in no time .... exp is everything :doh:
-
Hi all,
Made a small amount of progress tonight although it doesn’t feel like I’ve done much!
When I did that test run of the flywheel on the crank in its bearings I realised there were a few minor issues.
The first one was that I hadn’t yet carried out a method of attaching the flywheel to anything! :lol: I can’t remember why, I think I just got bored and decided to do something else! Anyway, it’s pretty essential so I decided just to use my usual method - drill an angled hole, tap and stick a bolt in it.
Here’s the set up on the drill (the first time I have used it during this project I think!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0221-03-07_0001.jpg)
I started the taper tap off in the drill at the same setting before moving it to the vice to finish:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0221-18-31_0002.jpg)
That was the flywheel done – ish! On carrying out another test run I realised something else- I the 4ba bolt to hold the flywheel on stuck out too far and fouled the bearing housing. So I just chopped it off and put a slot in it to make a grub screw.
Then there was a problem with the clearances between the bearing housings & flywheel which allowed it to move around and rub on the housing. This was because I got a bit carried away when doing the flywheel – I didn’t realise that the spokes actually have a slight curve from one side to the other, so because I was concentrating on getting the amount the boss sticks out on each side the same, the boss actually ended up narrower than the width of the flywheel!
Anyway, I decided to measure up and make some brass spacers to give necessary clearances and avoid rubbing.
I don’t have pics of the machining but I just turned some brass to a smaller OD than the boss, drilled a hole for the crankshaft and parted off. 2 x 0.5mm thick and 1 x 2.5mm thick.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0223-11-41_0012.jpg)
That pic was straight from the lathe, surprisingly there are no burrs, which is why I picked brass. Just gave them a rub on some wet & dry after this.
I skimmed 10 thou of each side of the flywheel outer rim to avoid any rubbing with the housings. Another test build showed that when the grub screw was tightened, it made the flywheel slightly wonky – :doh: Yes I have committed a cardinal sin! So I had to find a small piece of shim to pack under the side where the grub screw isn’t. That seems to have solved the problem. Being a cast flywheel the spokes aren’t very balanced or uniform anyway, there’s not a lot I can do about that but at least the outer runs true – ish!
Another little niggly job that I had put off was milling the slot in the piston and drilling the hole for the gudgeon pin. So thought I might as well get that out of the way too.
Set up in the milling vice. First I centre drilled and drilled 3 holes, 1 in centre then the 2 extremes of the slot. I should maybe have used a slightly smaller drill than the cutter but I used a slightly larger one.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0221-38-20_0003.jpg)
Joining the holes up with the 3mm milling cutter:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0221-47-21_0004.jpg)
At first I started taking tiny cuts, but then thought I’d try half depth – that worked so it only took a couple of cuts. Think I could have done it full depth to be honest but I am still finding the limitations of the milling machine. I’ve given it a bit of a slagging off recently, but it actually works pretty well, it’s just not the highest quality but I guess you can’t expect that anyway. Would love a Harrison one to match the lathe!
Here is a pic of the finished slot. It worked reasonably well. If I wanted a really accurate thing I would have had to use a smaller cutter then take extra cuts to come up to size. But I knew this 3mm would give a little more than 3mm, which is what I needed on this occasion. I don’t want any friction between the piston and con-rod.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0222-01-30_0006.jpg)
Now all that was left on the piston was to drill the hole for the gudgeon pin. For this I just clamped in the mill, lining the slot up parallel to the top of the vice jaw by eye. I also just aligned the point of the centre drill to centre and edge by eye - good enough for this since there is still scope for adjustment with this engine.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0222-16-36_0007.jpg)
Drilling the hole gently. This cast iron cuts like butter anyway though, a joy to machine.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0222-21-27_0008.jpg)
Test fit of the gudgeon pin material. 3/32” stainless. It is a lovely free fit but no play. The steel measured 2.36mm I used a number drill that measured 2.38 on the shank.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0222-23-18_0009.jpg)
Cut the gudgeon pin to length and faced the ends. 1mm shorter than the dia of the piston.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0222-28-54_0010.jpg)
The bearing surfaces will be those in the cast iron piston, it will be a tight fit through the rod so maintaining its position in the centre of the piston.
Here’s a bit of a mock up on the aluminium that will be the base plate:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0222-48-18_0011.jpg)
Unfortunately the glass burner I was planning on using won’t fit to give me the right flame position so I will need to make one.
I even remembered something for scale- the coin is a 2 pence piece. (Just over an inch dia)
It will certainly be the largest engine I have ever built. Can I still call it an engine if it doesn’t work?! :lol:
I’m not sure what to do with the edge of the aluminium plate. For the wooden base I will chamfer with a countersink as I liked the look of that on my rocking engine but not sure how well that will work on alloy.
Maybe I could do a stepped edge? Any ideas? Don’t think it’ll look great just square.
The finishing line is definitely in sight now I just need :whip: to get over it!:
Con rod
Base Plate
Wooden Base
Burner
Nick
:ddb:
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looking real good nick :thumbup: :thumbup:
you could use a router bit to shape the edges of the ali base, router bits were made for wood but they do a great job on ali and brass.
chuck :wave:
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Great Job Nick :clap:
Running a bull nose cutter around the edges finishes them off nice.
Have fun
Stew
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Nick,
Conrod, burner, RUN. In that order.
Get it running first, bling after.
You are only putting off the inevitable, so get to the running stage first, as you might need to make slight tweaks and could damage the bling. Then polish and shape away to your hearts content.
John
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Chuck / Stew -
I don't have any ball nosed cutters, might have to buy a few thought, they are sure to come in handy anyway. I was looking in a tool catalogue yesterday and saw a sort of engraving / chamfering tool that looked quite handy. people could make these themselves if they had indexable tips - it's basically a straight rod with the end milled flat and a 90 deg indexable tip bolted on. They were about £50 squid though - sod that!
Chuck, I think my dad has some router bits but not sure if he's got any small enough. What sort of speed would I need to run at for ali?
Bogs,
I usually jump the gun and try to run things before they are ready so thought I'd try to finish this one first as in the past I've forgotton about things like brown stuff bases and it's ended up looking crap! Do you reckon I should mount the stuff on a scrap, test base first to get it running then incase I need to move holes etc? Then make the real base and do finishing touches?
Cheers guys,
Nick
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Actually Nick, I got myself into the same predicament as yourself.
I got my twin licker running wonderful on a crappy base. Unfortunately it was at a time when I had loads of ideas for new engines in my brain cell, and I concentrated on getting them made and running.
Only now am I getting back to a couple of them, to bling them up, in fact one is destined to be started next week or the week after.
I don't want to restart the Halo project until Kvom has his up and running, as it is silly having two of the same sort of builds going on at the same time. So I am getting those engines up to scratch first.
In all honesty, you have made such a big dedication to this post, I don't think you would do what I did, and leave it unfinished. So get it running first by whatever means, only then finish it off to a high standard using the dimensions for the base of the running engine.
John
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Nick
As a one off you could make a D bit chamfering tool, nice and cheap and effective.
Have fun
Stew
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Good point John, I have done it before but as you say, this is my biggest and (hopefully) best project so far so I will definitely finish it. It just seems like more work making another base but better than messing up the real thing!
One of the good things about Jan's design is, because the columns are a flat bottom and screwed up from underneath, there is a slight margin for adjustment with slotted holes which would be hidden by the column bases.
Another good point of using a dummy base is so that I can see the overall , what's the word? Not foot print, but the overall max. dimesions of the assembly as I always like to try and leave an even border around each side.
I feel a bit apprehensive about this one, but other people have got them running and I know the only issues could be the fit of the pistons so it's just fingers crossed time I guess.
Nick
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Oh yeah, why didn't I think of that seeing as we've been discussing D bits :doh: :bang:
Actually, haven't got any big enough silver steel though, only got 3/16" is any other steel hardenable?
Nick
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Made a little more progress tonight. I thought I’d better turn that awful looking bit of brass plate I’ve been staring at for the last month into something – the connecting rod.
Started by finding a drill that would suit the 7mm bearing. Found one just under and did a test drill. It was ok, a sliding fit but I would loctite it. The brass was bloody hard stuff though.
Milled it square, to width and to length:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0322-41-19_0001.jpg)
Then marked it out a bit – well I knew what it meant! Incidentally this rod is 20mm longer than the drawings to account for my larger flywheel, slightly different design too.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0323-16-16_0002.jpg)
Back into the mill to drill the holes while it’s a uniform shape and more rigid.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0323-31-09_0003.jpg)
Wasting away the sides to give the narrow section:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0323-41-17_0004.jpg)
I then flipped it flat in the vice and milled the radii making sure I wasn’t climb milling. Stupidly, I decided I’d take a lick off the end but because it was only gripped by the narrow centre section the mill tried to pull it upwards. :doh: :wack: I really do some silly things sometimes! Luckily I backed off straight away and was able to clamp it back straight in the vice. There is a tiny machine mark on the end now but nothing to worry about really.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0400-23-59_0005.jpg)
Fitted to the piston and the bearing loctited in:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0400-38-43_0006.jpg)
Another trial mockup, nothing is bolted down here but it seems pretty good and if I bolt the bits in the right place it will be very free running so that’s the first tick in the box.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0400-45-35_0007.jpg)
It was really the first time I got to try the ‘pop’ test with the piston on the rod and something to pull on. The vacuum was more than I thought with the valve covering the port it took quite a bit of force to pull the piston out which resulted in quite a tuneful pop! So that made me a bit happier – ½ a tick in the box I reckon – don’t want to count my chickens!
Base, burner and brown stuff left to do! :ddb:
Nick
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That`s taking shape nicely Nick! :thumbup:
David D
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Good going Nick I recon we'll soon have a runner :thumbup:
Are you making the base out of ally? if so you could try making the edge trimming D bit from case hardened mild steel it may just work as a one off, I think Bernd used a one off mild steel cutter on his south bend indexer thread.
Have fun
Stew
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Stew,
Yes the base is ally. I think I am going to try the D-Bit route just for the experience if nothing else. I might be able to get one big enough for a chamfer out of the 3/16" silver steel if I'm careful.
If I went the mild seel route would I need case hardening powder or is there any other way you can do it?
Many thanks,
Nick
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Nick
You'll need the case hardening powder its the only home shop method I know, unless anyone else knows another way.
If you can hang on until next week I can get a bit of larger silver steel to you by the usual method.
Stew
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Stew,
Thanks for the info and the offer. I've just realised that with the way I had to machine the base - had to pack it on wood with edges over hanging. I could actually turn it upside down and use my 45deg dovetail cutter and take a small chamfer off the underside. This should work shouldn't it?
Here is last night's installment - I'm absolutely knackered, was in there until around 2am which is a bit silly but I just got into one of those moods thinking I am not leaving until I do what I intended!
I started by sawing the base to rough length and milling the sides in the vice to give the correct width.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0422-30-45_0001.jpg)
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0422-43-12_0002.jpg)
Unfortunately it won’t fit in my vice so I had to remove the vice and clamp it on 2 blocks of wood with the edges overhanging. So I clocked it with a little gadget for my dial indicator another member kindly donated. Thanks very much :thumbup:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0423-13-25_0003.jpg)
I milled the ends square:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0423-26-01_0004.jpg)
I then marked it up as a precaution.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0423-49-10_0005.jpg)
Drilled all the holes, centre drilling first.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0500-11-28_0006.jpg)
Then I realized I didn’t have any 2ba bolts, screws or anything! Pretty pissed off, I set about making some screws in a mad frenzy! Unfortunately, because I was rushing the shank size is slightly bigger than 2ba clearance size so I had to open the holes in the base up a bit.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0501-32-19_0007.jpg)
Everything bolted up quite nicely.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-0502-29-41_0008.jpg)
But I must have made a mistake somewhere in my calculations! :doh: :bang: Good job I took bogs advice and didn’t finish the base yet! The piston was not coming to the end of the bore, but at the other end it was sticking out by the same amount. This meant I had either drilled the holes too close together on the base – I was annoyed and about to re-drill / slot the holes, then I thought why – I can just shorten the conrod. So I did that and it means no damage to the base. It all looks how I intended so think I must have made the con rod wrong! Actually, come to think of it, when I wound the distance in using the milling machine dials I thought, that’s miles out … but put it down to the dials, I know them to be inaccurate over large distances – probably the pitch error on the lead screws. So I thought nothing of it and used my markings instead. Maybe I calculated the marking wrongly – oh well, no matter.
It spins over nice and freely so the only thing left to do was try it!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/th__00092.jpg) (http://smg.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/?action=view¤t=_00092.flv)
Unfortunately I couldn’t get a peep out of it, :( I was just holding the burner in different positions whilst trying to spin the flywheel but it didn’t show any signs of life. It makes a nice sucking noise and you could see it sucking the flame in and blowing it out if held in the wrong place. I need to have a proper look at flame positions, size of flame and timing of the valve now – I didn’t think timing would be an issue but maybe it is. I bit dis-heartened but I will keep trying, it can’t be that far away. If it still doesn’t show anything I’ll go for a new piston and valve.
Nick
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Just found this one which looks interesting! Good effort there! &feature=fvw
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Are you making the base out of ally? if so you could try making the edge trimming D bit from case hardened mild steel it may just work as a one off, I think Bernd used a one off mild steel cutter on his south bend indexer thread.
Stew,
I went back and checked that thread because I couldn't remember either. But it wasn't that thread. Somewhere around here I think I mentioned I made a counterbore using silver steel (drill rod).
Your right that you can make a one off to do that though.
Bernd
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Hi Bernd thanks for following that up
Cheers
Stew
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Stew,
I think I wrote that up about the c'bore overon HMEM. Now that I think about it.
Bernd
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Nick,
Don't under any circumstances give up on what you have already done and start making new bits.
First off, give the inside of the bore and pistons a clean out with meths. Just a small amount of oily substance or residue in there can stop it running.
Double check your timing first, then warm up the cylinder for about 20 seconds with a blowtorch, don't hold it in one place just play it all over, let the heat penetrate for a few seconds, only then give it a dose of flame at the port.
Notice where I have my burner, it has to be around that point somewhere, 1/2 a millimetre up or down or side to side will make all the difference to it running or not.
It took me hours to find the correct sweet spot spot for the flame.
Don't spin it over too fast, you will soon wear yourself out and also lose your temper, a gentle flick is enough. The engine will start to show signs of life when it is warm enough and the flame is near the correct position. It might only be a couple of extra revs on the flywheel, but you will get some sort if sign.
Perseverance is the way to win with this type of engine. Once you find the sweet spot and correct timing, you will be on your way.
John
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nick , as john said work with what you have made. all the parts you have made look good, these engines are a bugger to
get to run right but once you figure them out you will be very happy with what you have made.
keep us posted.
chuck :wave:
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Nick
As the guys say, keep at it, and keep your cool, and you'll have a runner.
Good luck
Stew
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Thanks for the encouragement guys.
I gave it a quick try while I was supposed to be making the tea last night! I gave it a quick clean first as there was a nasty brown deposit. Then set the timing and tried to position the flame as per Jan's and yours John. Still couldn't get anything out of it, but the characteristics seemed different. There was sort of more whooshing sound and the flame kept blowing out if I flicked the flywheel too fast. THis time the thing gummed up with that deposit really quickly. I am just using an old bottle of methylated spirits, is there anything I can easily get that will burn cleaner?
At this point I have an apology to make for being stubborn / not listening. You may remember me asking questions about the crankpin, and that John recommended doing it in a certain way. Well I stubbornly did it my way, the way I had done on my hot air engine. This was for 2 reasons, 1. to make it simpler to make, and 2. because I wasn't mega confident everything would be dead straight so I thought allowing a little floating of the bearing on the pin would let things self align. Well I think it all is pretty much inline, but because of the relatively long rod, it does float quite a bit side to side, sometimes getting close to the crank disk. I can't feel any undue friction and it doesn't seem to touch it ever but it is annoying me now. The other main point that John mentioned at the time was ease of disassembly to clean everything out - well on mine, it's not exactly easy to take to bits. So it'll be getting a nice knurled screw (if I can manage to do a nice knurl - not done that since uni days) as Bogs suggested with the right clearances built in. So feel free to give me a :poke: and :wack: and I hope you accept my apology, I didn't do it blindly - I had a couple of reasons but I should have digested what you were saying more.
I was also trying to think which way would be best to spin it, but it really shouldn't make any difference at all.
Jan suggests a small clearance between striker assembly and cylinder when at TDC and when at BDC there should be about 1-1.5mm overlap of the valve and port. Is this about the same as yours?
Thanks,
Nick
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Quick check in.
Last night I realised a difference in the way Ihad made the valve rod which may have affected things. John's rod has a 90 deg right angle silver soldered - this allows limiting the travel of the valve into the cylinder and Jan's new method with the bend is bent in such a way to limit this. Mine however, ended up with a slightly different bend allowing the valve to travel further in which could alter timing. So I turned up a coller with a set screw in it to limit that travel, just as I can at the other end by the striker block.
Tried the engine again, still no signs of life that I can detect. Sometimes it sounds like it might kick a bit but that could be my mind playing tricks! I'm at a bit of a loss what to try next. I think it is set up as per the plans and it seems to pass the tests Jan suggests. If anything, I've never been happy with the fit of the piston / valve. I might need to re-lap the bore and carefully make a new piston and valve.
It also needs a burner and base making to stop it wobbling about and me having to hold the burner in place.
So still trouble shooting. I thought it might be tricky this one!
Nick
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WOW Nick :bugeye:
great looking engine ,great build log too
Regards Rob
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Thanks Rob!
Noticed you said great LOOKING, that's all it is at the moment if I can't get the damn thing running! :(
Keeping all my fingers and toes crossed though.
Nick
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Nick,
Make the burner first before making anything else, you just cannot hold the flame steady enough by hand for the engine to fire up, as I have said before, the flame position is the most critical part, that is why mine are screwed down, they can't move out of position.
John
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Ok, thanks John, will do. I've spent the last 3 nights pratting about trying to get it to run but without a proper burner! I've studied all the other internal valve flame lickers I can and it all seems to be in order. I think this is where I need to be patient and methodical - oh dear! :lol:
Nick
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Hi Nick
i did not mean it that way :doh: , i no these engines can be a pian to setup ,,,,O i did call into Darlington Steam :bugeye: they do some big stuff with a big price tag
Regards Rob
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Rob,
No worries, just kidding! :lol:
:offtopic: Those prices are astonishing aren't they! :jaw:
I just noticed that some are on ebay too now think must be same company - we are talking more than a lot of peoples homes for a 6" scale traction engine!
http://cgi.ebay.co.uk/NEW-6-Scale-Fowler-Traction-Engine-LIVE-STEAM_W0QQitemZ280432658216QQcmdZViewItemQQptZUK_Trains_Railway_Models?hash=item414b16c728
Nick
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Hi Nick
yep i had the name wrong ,thats the company ,,,,,,,,,,,The Great Northern Steam Company,,,,,,,,,,,, sorry :offtopic:
Have you made the burner for the engine ?
Regards Rob
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i'm paying a lot of attention to this now i've decided i'm building one of these.
i so look forward to your "its a runner" post :thumbup:
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Unfortunately not Rob! Distinct lack of shop time - I chose to do something different tonight - played badminton and caught up with a mate at the pub. I do think about this engine about 80% of the time at the moment though which is quite annoying! I might make a start tomorrow and Fri night and hopefully on Saturday morning I should get a good chunk of time to myself as the wife and kids are off to see grandad and grandma without me! :ddb:
So fingers crossed by the end of the weekend, the engine should be 'finished' and I should know what action I need to take to get it running!
Nick
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Be very careful Jim with these types of engines, as Nick is finding out, they can be a soul destroyer, and with only a slight push, could put you off making model engines for life.
This one that Nick has made deviates a lot from the normal practice for this type of engine, so if you really wanted to make a flame licker as a starter project, I personally would start with one of the more common designs, with the sucky in bit on the end of the cylinder head.
I have been having a bit of a discussion with Nick, and have come to the conclusion that the way to go with these engines is a change of fuel. I actually knocked up a basic gas burner for mine, and the engine ran lovely with it, unfortunately my burner design wasn't 'clean' enough, and the engine got choked with unburned deposits and needed to be cleaned out between runs.
Then I found these,
http://www.jerry-howell.com/Propane.html
Having purchased the plans, they look fairly easy to make, a couple of D-bits to make the venturi and the rest seems to be very straight forwards
To make the jets for the above, even though Jerry sells them in an American Imperial size, I want to make them in metric or English Imperial, then I have still to construct a very high speed drill. I have all the bits to make it, and is a very similar design to Jerry's
http://www.jerry-howell.com/Micro-DP.html
Only mine will be air powered, as that seems to be the best way for me to reach the speeds required for 'stable' drilling. Over 60K rpm should give enough centrifugal speed to the drill bit to enable fairly rough handling and feed of the drill without breakage. Just to see the sizes of drills that are needed, look at the pic below. The big one is about 1mm diameter, the one at the opposite end is the size required to drill the jet, 0.15mm.
This isn't meant to detract from Nicks post, just as an add on to give an insight into what can be done if you want to pursue it.
John
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I would concur with John on this one Jim. It looks a simple design, that's what attracted me to it but with hindsight, I think the simplicity gives it less control and means things need to be more tightly controlled. Last night i was actually looking at the poppin versions with a sliding valve operated by a cam. Although this initially seems a little more comlpex, I think it is a much more proven design.
John,
Those burner's sound excellent but I think are beyond my capabilities. As you pointed out, you need the specialist drill too.
Nick
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Hi all,
I know this has gone a bit quiet but I haven’t given up on it! If I’m honest, I am a bit disappointed that it didn’t run and I couldn’t even detect it trying to run. It passes I think the tests on Jan Ridders problem solving page. If anything I’ve done is a bit marginal, I think it was the cylinder and piston tolerances.
I haven’t done nothing on it, I spent a few nights messing around trying to get it to run but nothing. Then I thought, just finish the thing off and then try to troubleshoot. So I started by finishing the aluminium base off.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-1215-02-40_0002.jpg)
I sanded it with the bosch mouse sander then got a stick with some wet & dry and rubbed it back and forth a bit. Then I did the same with some white spirit which gives a sort of matt sheen to it. I could really go to town polishing it but it takes ages to get the machining marks out completely so this’ll do for me. I haven’t put polish anywhere near it, just a quick rub with some wet & dry and oil seems to give a nice finish in my opinion. I decided not to put an edge around it as I’d probably spoil it if I didn’t take care in clocking it square on the milling table.
After this, I could then make the base from some brown stuff. This needed little counter bores for the screws underneath the alloy base. I was wondering which way to go to fasten it down. At first I thought, could make some nice hex bolts and bolt from top. Then I thought I could keep them hidden like the rest of the engine, but then I found some 0 BA screws with nuts so decided to drill through the lot and leave the nuts on top as a sort of feature. This meant giving my nuts a bit of a polish so to speak!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-1215-02-29_0001.jpg)
Again, this was sanded with the mouse and oiled with teak oil. I did put an edge around this with a countersink in the milling machine. It worked ok but it was a mess on getting it clocked straight.
Then I decided to re-do the crank pin. As discussed before with Bogs, it’s better to retain the big end with a set clearance to stop it wondering. So I made this from stainless:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-1216-20-15_0004.jpg)
Along with a little bronze spacer. This is the first time I’ve ever knurled anything since uni. The set of knurls I have are sort of sprung and you turn a screw which makes them closer together (need a pic!). I didn’t really know how much to tighten it so I went easy, but then of course you can’t go back and do it again incase it goes in a different place and mashes it up so the knurl isn’t very deep! I should have pointed out that it's a 2p coin in the photo! Not sure why I put it that way around!
I then assembled the engine together. Here are some pics, looking much better on its real base!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-1216-33-50_0003.jpg)
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-1216-34-26_0005.jpg)
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-1216-34-54_0006.jpg)
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-1216-35-10_0007.jpg)
Hope it doesn’t stay in here for the rest of it’s life! :
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-1216-41-00_0012.jpg)
The base was needed as it was wobbling about when trying to flick the flywheel over. Now it’s very stable so it will give me a better chance when I try to get it to run in anger!
Almost forgot to mention that I re-lapped the bore and made a better fitting piston and valve. How much better remains to be seen though! I also took the opportunity to extend the spigot on the piston slightly as I noticed my port wasn’t opening quite fully – not sure why, I must have calculated something wrong.
All I need to do now is the burner, then I am hoping my little tweaks and improvements are enough to get some life out of the thing. If not, I’m a touch puzzled. The only real thing I can think of is that I may have to revisit the cylinder and pistons again. I have a sneaky feeling that when I lapped it, it may have taken a bit of parallelism & circularity out of the bore. I think I have some adjustable reamers which may correct that, then make new piston and valve again.
There are another couple of suggestions with regards to the mass of my piston and valve as they aren’t hollowed out and the only other things that are different are the flywheel and con rod length. If anything the conrod length should improve things though and the flywheel should be ok, it should be better and don’t think it’s any heavier. If things such as the mass of the piston affect it’s running, it is, as I thought a marginal design.
Here is a little video flicking it over by hand, sorry about the lighting!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/th__0008.jpg) (http://smg.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/?action=view¤t=_0008.flv)
So, hopefully will get started on the burner tomorrow, and by the weekend, fingers crossed I’ll have some good news. But I’m not holding my breath, could be back to the drawing board I think!
Nick
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Looking good on the base Nick :thumbup: :thumbup: :thumbup:
Your little tweaks I'm sure will get it running.
Stew
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That is a very neat looking build you have there Nick, you certainly are making a finished job of it :clap:
Be nice to see it running though :dremel:
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To be honest, I'm pretty gutted it doesn't run. I haven't put as much care and attention into anything before, and I think it's a good improvement on all of my other builds. Maybe it's a step to far too early.
I still have options though. If it doesn't run now, hopefully I can get things nice and true and parallel with the adjustable reamer and plenty of oil, the only issue is the wall is getting pretty thin now, so if that doesn't work it'll need sleeving but still all is not lost.
If that doesn't work I'll be stuck for ideas and it would mean certain features of the engine that shouldn't be critical to it running, in fact are ... at which point I'll try making the poppin flame licker! There are a lot more examples of that running, infact that is one of the first engines I used to just stare at, mesmorised at exhibitions and steam fairs when I was a teenager! I have seen tiny flame lickers in the past that run really well and should only have a fraction of the power of this comparatively large one, unless this isn't a particularly efficient design.
Nick
ps I have also seen another design but never seen one working. I actually thought of this myself but then when was doing some research realised that somebody had infact already thought of it! :doh:
It's a very simple idea so probably a lot of people have pondered it. Imagine an oscillating engine or wobbler but with the exhaust port not drilled. On the down stroke it sucks a flame in through the inlet port and once it gets to bottom dead centre the port is closed - it is effectively sealed. Gases cool down causing the under-pressure and atmosphere pushes the biston back to TDC. The only issues I see here are that the seal relies on a pushing the faces together which would cause a bit of friction., and the timing is implicit in the design. Although by drilling the port in the right place you might be able to tweak the overlap etc. This could be worth experimenting with but is a bit of a journey into the unknown and likely to make me even more :( and :bang:
When I first set my workshop back up a few years ago, a guy on CNC zone posted a pic of such an engine and one of his own which was unusual too (see attached)
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Got a bit done on the burner last night! Took me ages for some reason, I didn't have the metal to hand, then I couldn't decide how to do it! I will post pics of progress later on tonight. Got the bottom of the burner done. Out for a team building thing tonight, 10 pin bowling and a few drinks so doubt I'll get in the garage until Saturday night now. But this weekend should see the burner finished off. Then it'll be testing the engine and probably deciding what I need to re-work.
Nick
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Made more progress last night and finished the burner for the engine, which completes the last piece of the engine – but unfortunately not the last piece of the puzzle :o( More on that in a bit though!
Here’s how I did the burner:
I had a bit of copper tube in mind, only slight annoyance is it had some sort of plating on it. Turned up a nylon bung to fit the tube as I quickly realised I was just going to crush it in the chuck.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-1622-56-26_0002.jpg)
Faced off to length:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-1623-01-21_0003.jpg)
I have about a foot of 1 ¼” ish cast gunmetal, have no idea where it came from but I decided to use that for top and bottom:
Facing and putting register on:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-1623-07-46_0004.jpg)
Parting off:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-1623-40-53_0005.jpg)
Good fit:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-1623-57-50_0008.jpg)
Ready for soft soldering, I just used some electrical solder and some of that soft solder paste stuff which acts as a good flux:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-1700-01-46_0009.jpg)
After a little cleaning up:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-1700-10-26_0010.jpg)
Facing off due to parting pip:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-1700-16-04_0011.jpg)
Here it is with the bottom soldered in place and a bit of polishing. I haven’t fully got the plating off but it’ll do!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-1700-41-23_0012.jpg)
Turning the top was pretty much the same as the bottom; just put this pic in to show the weird difference in surface finish part way across the cut. Must be something to do with the way it’s been cast.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-2022-25-14_0001.jpg)
I drilled an air hole then a hole angled at 22.5 degrees. I was worried I wouldn’t get close enough to the cylinder with the wick if not. I then turned a stainless steel bush and loctited it in before a bit more polishing. The fit of the cap is a tiny bit tight really, well, it’s just there’s not much to grip to get it off! A pain when it’s ½ full as you tend to spill meths! I was originally planning on putting a little knurled knob on it but couldn’t be bothered!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-2100-24-17_0006.jpg)
Pic of it on engine base:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-2100-44-13_0007.jpg)
I tried to run it again tonight unsuccessfully. I did find out a few things though. On mine, it seems some sort of lubrication is going to be essential. Without it, the meths I’m using puts a nasty deposit on it pretty quickly, jamming it up. But with oil present, it doesn’t build up.
I’m not sure why it won’t run but have been in contact with Jan ridders who is going to do some experiments on valve timing and let me know the outcome. I just can’t get much out of it at all. The most promising results were when I slackened the rear collar off – this means that when the valve shuts, the suction pulls it further into the cylinder. I then almost get a sort of power stroke if the flywheel has enough momentum to carry it over – however, at that point the valve gets a bit tight in the bore so I clearly have clearance issues. If I take a little off it to avoid it being tight, it’ll probably not be sufficiently air tight. I think I may need to ream the cylinder bore out and make new piston and valve.
Also, at the same time, because the valve got stuck, me spinning the flywheel loosened it on the crankshaft and because I’ve stupidly put the grub screw somewhere I can’t get at, It’ll have to come to bits to tighten back on. In doing this though, I found another possible issue. When the flywheel was loose, I moved the conrod manually with the flame present and if I quickly put it past bdc, I felt a definite power stroke trying to pull it back. So I’m thinking of trying an experimental aluminium flywheel as I fear my big dia. Cast iron jobbie might have too high moment of inertia.
Another thing I noticed whilst studying the pictures, tips etc on Jan’s site was that his wick is about 2 x the diameter of mine. So maybe the width of flame needs to be much bigger. Not sure if I have scope in my burner to go quite that big so would need to re-make the lid.
Sorry if all that is difficult to understand. I find myself rambling when things aren’t going to plan! When I looked at the design of the engine, I didn’t think there were many variables as they were inherent in the design – how wrong was I! Still, hopefully I’ll get there one day.
Disappointing but lots of things to try. I just need to do them in a logical order.
Nick
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It sounds like it wants to go Nick, Have you tried running it in by connecting it up to a motor/drill and letting it run for 1/2 hr with plenty of oil just to get rid of the tight spots.
Good luck
Stew
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Thanks Stew,
No, I haven't tried that but might do so it sort of laps itself in in the right place naturally. think the only thing that could happen really is the con rod could bend. If I adjust the collar so as to not let it go too far in that might work though.
Need a plan of action but don't think I'll get a great deal done over, only got tomorrow night before xmas really but might get a couple of nights over the break.
nick
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Nick - I know your a far more competent machinest than me but I have found that my engines have always run much much better after running in for a short time. Infact, my first one would only run upside down! I ran it upside down for an hour and when I turned it over it was fine!
I think it is definately worth hookling up a small motor to turn it over for 30 minutes or the best part of an hour.
Looks amazing, bummer it is not running but I have every confidence it will do!
Chris
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For a very fine clearance how about a little talcum powder in the bore? I understand it is a lubricant but it is also an abrasive (if such a thing is possible). Maybe someone know more about the stuff?
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Nick, nice work :clap:.
If the engine gives a noticeably kick, as yours, it means, that you are on the way to get the runner.
That type of engine is known to be notoriously critical about the adjustments. I have built different types of them in the past, and none was successful.
When looking at Jan Ridder's engines, he must have some magical touch, as his engines run quite happily.
Anyway, keep at it :thumbup:.
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Thanks guys. I do need to keep at it.
Chris, I wouldn't say I'm more competent at all! I think I will try running in, it does make sense as the tight spot isn't very tight but I think if I tried to lap any further, the tight spot would become a loose spot! I don't actually think the valve should travel that far in anyway though, I think I just got excited because it did something!
No disrespect to Jan as his stuff is wonderful and it is a very innovative design, but I just think things are very critical to get them to run. As I said, I read through the poppin instructions yesterday and a lot of things in that make a lot of sense. If I try that one at least I'll know whether it's just me or not! Even in those instructions it mentions about how critical the fit of piston and friction is though and the fact it can bring a grown man to tears!
Having said that, I have seen a few versions of Jan's internal valve engine that work very well - Jan's, another couple on youtube and Bogs'. All these people are much more experienced / better machinists than me though!
John, talcum powder sounds a good idea, I also thought toothpaste but that might be too coarse?
Nick
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Nick, I think tooth paste would be much more abrasive than talcum.
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Ok, might do a test with talcum on something that doesn't matter! I really need to get better at boring holes and lapping things - I think this might be my downfall.
Nick
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Hello, hope everybody had a nice Christmas and are looking forward to the new year.
I made a lighter flywheel tonight, tried the engine again and am afraid to say the next remedial action I take will be the last resort! :(
The flywheel didn't seem to make any noticable difference. At a certain setting I think, although it's extremely difficult to tell, that there is some tiny sign of life. However, I am puzzled as to why it is so small, so it might be psycological! This only happens if I put plenty of oil on the piston and valve, which is understandable as they will make a better seal with oil, but I would have thought with this seal and very little friction I would at least be able to clearly see the engine trying to turn over or a power stroke. If I set the valve up so its travel into the cylinder is not limited - i.e. it get's pulled further in causing more overlap with the port, I think I get some sort of power stroke but then the valve sticks - surely this can't be the right way to set it up though as some of the power stroke will be wasted pulling the valve in at the same time as the piston.
Anyway, the only thing left to try really is reaming out the cylinder with an adjustable reamer (luckily I have found one the right size range) to make sure it is perfectly round and parallel - it isn't at the moment which is why the valve sticks. Then I will have to make a new piston and valve so will need to go and buy some more cast iron. I will also take the opportunity to make these components to the drawing this time, i.e. hollowed out incase this 'quenching' phenomonen people have talked about has any effect.
If those things don't work, along with a larger burner wick, I will just have to put it down to the fact my machining isn't quite up to the job yet! At which point, after having a good cry, I will start collecting materials together for 'poppin'. I get the impression this might be a tiny bit more forgiving but I still think it'll be a challenge - hopefully if nothing else I'll be able to learn a few lessons from my first flame gulper experience!
Here is a pic of the engine with experimental flywheel:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-2900-35-19_0001.jpg)
Not pretty but gave me a chance to try out some of my christmas pressies:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-2520-38-37_0001.jpg)
:offtopic: Not shown in there was a set of carbide tipped lathe tools and a set of metric taps & dies. The idea with the carbide tools being that it will save me a lot of time setting tool heights, if they are all the same height I can make 1 piece of packing the correct height.
Unfortunately I didn't do my homework very well and the 8mm shank ones are a bit small for my lathe really. Still seem to work really well, I only tried what I assume is a roughing tool on the aluminium flywheel and it gave a cracking finish as long as I kept cleaning the build up off it and had the speed higher than usual.
Also tried a 4mm tap and die from the axminster set which worked well except the T type tap wrench which didn't seem to grip very well - I think the tap was just too big for it.
The keyless drill chuck that Bogs recommended from RDG really does look amazing quality for the price but they have sent a MT with a tang on it and it won't fit in my milling machine, too long I think so can't try it yet.
Other things include a de-burring tool which works nicely for holes. A small metric tap and dies set, slide way oil and cutting oil, a tailstock die holder and a wiggler set, which if anybody knows how to use, please tell me!
Nick
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Nick,
Put the engine aside for a while. Perhaps one day you'll have an "Ah ha" moment and get it to run.
Nice pressies by the way. I've got tool envey. :clap:
Bernd
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Bernd,
I think that's what it needs! I'll do the things I'm thinking about whilst they are fresh in my mind but then I will do as you suggest and move on. I will need something to pick me back up and put a smile on my face after this! I don't want to jump out of the frying pan and into the fire though so I'll be extra careful with my next project!
Nick
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Nick, if in doubt about the cylinder and piston not sealing well enough, consider making new ones. But don't do it in a hurry.
Especially the lapping is most tedious part, but if done slowly and carefully, it definitely pays back :thumbup:.
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Good advice from Bernd,
Good chance in the next six mths you'd read something somewhere, or make something that'll give you a :doh: moment and you'll run back to this little project and get it running just fine :thumbup:
I often put things to one side for later when a bit stuck .... :scratch:
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I often put things to one side for later when a bit stuck .... :scratch:
I must really be stuck by the amount of projects waiting to get finished. :lol: :lol:
Bernd
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I had a decent night in the workshop last night. I reamed the cylinder with that adjustable reamer and plenty of oil. The bore is now very round and parallel compared to before. I am not going to bother lapping at this stage as I think the finish is smooth enough. I also turned an aluminium valve - this may be no good, it was more of an exercise to find out what a good fit is. I turned one to a few hundreths of a mm below the bore size and it is a much superior fit than before. Slides freely yet seems very air tight without oil. I will probably give it a try, until I can get some more cast iron. I just need to do the piston to the same standard now. Not sure whether to try aluminium again to keep weight down or gunmetal which would probably be better for the application. It's just the differential expansion that I'm worried about - it could bind up when the bits get hot. I can only try, if it doesn't work after this I'm at a definite loss - the fit is definitely good enough now, and it is the same at any position now.
Nick
ps I had a reply from a French chap that had made one and showed it on youtube. He was quite helpful with timing figures and directed me to a french forum - this was the first bit I clicked on:
http://www.blooo.fr/forum/viewtopic.php?id=2403&p=1
Nice finish on that one!
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thats a work of art!
are you going to try an ally piston?
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Jim,
I think I might try one as it looks like the shop where I was going to get my cast iron is having a xmas break! The ally seems ok for the valve, but that's without any heat and there aren't any sideways forces on the valve. So I fear the combination of the differential expansion and a bit of sideways force on the piston may cause binding with the ally. For what it takes, I think I'll turn one up from ally, even if it doesn't run I'll be able to tell you if the friction dramatically increased etc.
I could end up making 3 sets of piston and valve at this rate and I have already made 2 or 3 before hand!
Nick
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Hi all,
Got more done in workshop last night - got the valve finished and the piston made, both from aluminium this time. All was going very well until I used my new tail stock die holder to thread the bit that goes inside the piston for the wrist / gudgeon pin and it snapped! I think I’d done the undercut too deep, so I did it again without an undercut! Luckily it didn’t take long the 2nd time as everything was set up. It took me ages to get the vice clocked back square on the milling machine etc.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-3117-46-15_0001.jpg)
The piston is pretty much to Jan’s original design now, just the wrong material!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-3117-46-25_0002.jpg)
Anyway, the piston and valve both had a very nice fit. Excellent seal whilst hardly any friction.
It was 00:50 hrs by the time I finished that so I thought I’d leave test run for today. Just tried it and there was good and bad news!
Here is the good news:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/th__0003.jpg) (http://smg.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/?action=view¤t=_0003.flv)
This is actually quite a bit more free running than before and with a better fit, that can only be a good thing.
However, when I pre warmed the cylinder to get rid of any condensate first, my worst fears came into being! I half expected this to happen!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/th__0005.jpg) (http://smg.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/?action=view¤t=_0005.flv)
The engine had seized completely due to the aluminium expanding faster than the cast iron! :doh:
So at least this exercise tells us something we thought anyway - it’s not easy to use aluminium pistons with cast iron where heat is involved! It may be possible with the correct clearances though – not sure how to calculate this and have no desire to. :smart: I’ll have to wait for some cast iron now.
Promising though, If I can achieve the same fit with the cast iron there SHOULD be nothing stopping it from running!
Here is a pile of scrap – there were a couple of other components that got shot straight in the bin in anger – at least the experimental flywheel can be saved for future projects!
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/2009-12-3117-59-28_0007.jpg)
Nick
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i'm gutted! :doh:
i really thought it'd run!
like you said to me before about using the "correct" material!
looking forward to the cast iron piston being made :thumbup:
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i'm gutted! :doh:
i really thought it'd run!
like you said to me before about using the "correct" material!
looking forward to the cast iron piston being made :thumbup:
Me too!
I really thought you had sorted it this time Nick.
Onwards an upwards........ :thumbup:
David D
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Jim,
Maybe an aluminium cylinder and piston would work? The only issue I see is the aluminium is relatively soft, although I'm using 7075 (i think) it still seems to score quite easily so it might cause unnecessary friction. Worth a try perhaps.
Can't get the cast iron probably until friday :( unless I can get away from work early one night!
Nick
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Hi, Happy New Year to you all.
I feel I’ve made a pretty big step in the right direction over the weekend. On the off chance that it was open, I rang the metal place on Sat morning as we needed to go into town to find a new internal door. We can feel the draught from the utility room when in kitchen with this cold weather - the previous owners, for reasons only known to themselves took off the door and put it in the garden! Anyway, the metal place was open, so I got enough metal to do a new piston / valve for this engine and make two 'poppin' engines! Not bad for £16 squid, I like the fact that I can just work direct to proven drawings with known materials at that price.
Anyway, digressing again, I will just call the piston and valve pistons from now on as it’s annoying the heck out of me! I was allowed into the garage on Saturday afternoon to make new pistons from the cast iron bar as I couldn’t wait! I made them as good a fit as I could. That was the same dimensions as the alloy ones I made. They felt slightly sticky at first but a few strokes up and down in the cylinder knocked any high spots off. I’m sure people have got better fits than me, but I don’t think I’ll get them any better. The bore of the cylinder and the surface of the pistons weren’t polished, I didn’t do any lapping this time, the bore was reamed with an adjustable reamer with plenty of oil and the pistons were just turned with new carbide cutting tool with the slowest feed. They both have a very smooth feel to them and I think better like that than if I tried to lap them and make them not parallel or round.
I carefully cleaned and assembled the new components and spun the engine over with a flick of the flywheel – it ran very freely but made a nice sucking noise as with the alloy pistons. So I decided to try it. I warmed the cylinder with a pencil torch first then lit the meths burner. I was shocked when the engine started to pick up on it’s own. This was with the original cast iron flywheel incidentally. I watched in awe for a few seconds then rushed for the camera but by the time I got back it was slowing down and came to a halt. There was now some friction present, the meths I am using seems to put a nasty brown deposit on everything. So I tried some 3 in 1 oil but immediately noticed as a lot of people have said, it caused too much drag.
At this point I had arranged to go to a friend’s, but I went with a spring in my step and couldn’t stop thinking about it – I can’t be far away.
I’ve had another couple of chances to try running it since. One session late that night when I got back, and one on Sunday afternoon, both not totally successful though unfortunately.
Here is a short video from the first:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/th__00032.jpg) (http://smg.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/?action=view¤t=_00032.flv)
I seem to have found the optimum flame position for mine, which is very strange – it’s actually the other side of the port which is bizarre. The next best position seems to be where Jan Ridders suggests and Bogs positioned their flames but it doesn’t seem as good there, the flame gets blown about more.
Another thing I tried was changing the flywheel to the alloy one. That doesn’t seem to have enough inertia. It won’t carry it to the next stroke more than a couple of times and sort of kicks back. But maybe the big one still has too much – not sure, I don’t think so otherwise it wouldn’t run for as long as it did probably? I don’t want to take anything off the flywheel anyway because I can’t add it back on!
The engine seems to run for only around 30 seconds before it gives up the ghost. I think there are a couple of reasons for that, 1 is the deposit I am getting from the meths. I need to try to get hold of some denatured alcohol which is supposed to be better in that respect. The other thing is, as everybody has mentioned, they are very sensitive to flame position and the flame getting out of shape. I’ve noticed that I am using a wick ½ the diameter of what Jan suggests. Only 4mm instead of 8mm. That larger width of flame might give it more stability.
Here are two more runs, please excuse the noise from the kids they weren’t aware of the significance of this moment in my life! I was going to try and edit these for the best bits but might as well show them warts and all incase anybody picks up on anything.
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/th__0001.jpg) (http://smg.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/?action=view¤t=_0001.flv)
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/th__00052.jpg) (http://smg.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/?action=view¤t=_00052.flv)
In the last video, when I start it the final time, you can actually see the engine accelerate a little when I shoved the burner right into that corner in front of the port. This pleased me somewhat. Also in the last two videos I was using some very light oil which worked wonders on my stirling engine. Trouble is, I don’t really know what it is, it came with some electric hair clippers! The oil seems to prevent build up of the residue whilst maintaining a good seal and keeping friction down when hot.
So a couple of things I am thinking are:
1. I really need a larger diameter wick, so I’ll make a new burner cap with larger wick tube.
2. I need to try some denatured alcohol if possible, hopefully without nasty residues.
3. Could I make a drip feed oil cup at each end of the cylinder like ‘poppin’ has. The author of that article swears blind the oil feed is necessary, he suggests sewing machine oil. Marv has also backed this up with ‘Poppin’. Mine does seem to like the oil. When it stops and I re-apply a couple of drops of oil, it restarts again no trouble and doesn’t get snarled up with residue. However, the denatured alcohol may solve that, or a special gas burner like Bogs suggested earlier in the thread.
I’m feeling a lot more optimistic now, still some way to go but some encouraging progress. Thanks to all for your interest and input.
All the best.
Nick
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Well done Nick looks like you've got this one licked
:clap: :clap: :clap: :clap: :clap: :clap: :clap:
As you've done you just have to go back over things tuning as you go, and gradually you get on top.
Get the bigger wick sort out the meths and the oil and you'll have a real good running engine.
Have fun
Stew
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Thanks Stew,
I hope so! Somebody mentioned that my flame doesn't really look right and it just occured to me that my meths is probably over 10 years old! Wonder if it's hydroscopic or something. Either way, will try some new stuff, hopefully the purer denatured stuff if I can get my hands on it.
Nick
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Blummin well done Nick! :clap: :clap: :clap:
For toy steaming, hot air, & flamelicker engines, I now only use 5w-30 fully synthetic motor oil...... Far superior to 3 in 1 in hot situations. :thumbup:
I cadged a half empty 1 ltr bottle from the service station, at my last MOT test. :D
Not used `em myself, yet. But these suppliers are recommended for industrial meths.....
http://www.rydenor.co.uk/index.php?cPath=51&osCsid=1293448a229999a03d1c967732bda334
http://www.wood-finishes-direct.com/products/wood-finishes/thinners/industrial-methylated-spirit.htm
David D
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Thanks David,
will try the engine oil. Don't have any fully synthetic at the moment but probably will when I service the car in a couple of months!
Will have a look for this meths!
Nick
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Hi all - update on the engine:
I had to come home early from work yesterday afternoon so I took the opportunity to go and buy some Industrial Denatured Alcohol (Industrial Meths, which is 99% ethanol). Luckily there is an oil / paint / chemical merchant near by called Smith & Allan. Cost me £16.02 for 5 litres.
Tried the engine last night with the new fuel and with the wick in the strange position that I found best before. With the tiniest touch of the flywheel it burst into life straight from lighting the burner! I was gobsmacked, it was running away with itself, never seen it going so fast, but then it stopped. Partly because the flame was twitching around so much at that speed and partly because some condensation built up.
I restarted it, here is the video - it didn't go for long but probably longer than it had done, still going at a fair rate! This was with the oil that was left from the previous run a couple of days before, but I'd run out of that electric razor oil now:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/th__00012.jpg) (http://smg.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/?action=view¤t=_00012.flv)
After this it was a bit of a pain and I was fiddling around for quite a bit to get it started again, probably took a while to warm up. But then i decided to try some engine oil as suggested by David D and Mike R C on HMEM. I only had 10w40 semi synthetic which is a bit thicker than the 5w30 suggested. Anyway, I tried some of that as well as messing around with flame positions again. I also put a drop of oil down each side of the flywheel and on the push rod etc.
Bizzarely I then found a bit of a sweet spot for the burner that seems to make it run not as fast, but more consistently - funnily enough, this was where Jan Ridders suggests and Jeroen Jonkman and Bogs have theirs on the other side of the port.
This is the longest video I captured as before whenever I reached for the camera it stopped! It had fun for a couple of minutes before I started this video and it only stopped because it ran out of fuel this time! You will notice the different flame position and you might notice that it is running in the opposite direction. It seems to run the same in either direction, it’s just that this one tends to try to tighten the crankpin rather than loosen it.
:ddb: :ddb: :ddb: :ddb: :ddb:
(http://img.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/th__0002.jpg) (http://smg.photobucket.com/albums/v287/NickG24/My%20Flame%20Gulper/?action=view¤t=_0002.flv)
I then filled the burner back up and tried again, it ran until the burner ran out, which was probably over 20 mins only stopping a couple of times on the way due to the flame fluttering a bit too much. I think a larger wick would give a more stable and wider flame which would help a bit. What also happens is the engine speeds up, then the flame gets blown around a bit and it slows down, flame stabilises and it picks back up again. Anyway, it did a stint of over 15 minutes continuously.
I tried to run it again today but because the oil had thickened up with reduced temperature it took a few minutes to warm up but then settled into that steady rhythm again. :) :D I’m absolutely chuffed with this project now and I consider it complete. I was going to open some Cava we have in the fridge to celebrate but the wife wouldn’t let me :lol:
Only problem now is, what to do with all that metal I bought for ‘Poppin’. I might try to design a Hit & Miss IC engine based on the design of poppin.
Nick
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I'd just like to give a big thank you to everybody for their interest, support, encouragement and advice! :thumbup: :bow: :mmr: :nrocks:
Nick
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Well done Nick -fab engine
Gerhard
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I'm glad you got it running Nick! Way to go!!!!!
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Hi Nick,
I'm brand new on this forum, having just found it, and I've been following your project with great enthusiasm, because I built a much smaller engine of that type years ago and never got it to even consider running. In reading all the posts, I've seen a couple of things which might be part of your difficulties, all through the beginning, it seemed like the normal having to work out the bugs, but when you got the new iron piston and valve in, and it started up, only to quit, it seems to me you are dealing with the real bugger of these engines, friction. The note of condensation suggests where a good part of the friction comes from, and pre-heating it would probably eliminate that. I found in my own engine, any oil at all stopped everything dead up. The instructions on the engine I built said to use a pencil and rub the lead all over the piston and cylinder (both were made of aluminum), as graphite is a great lubricant and dry powder.
With your success, I'm going to go back and build the one I tried before, again, only with your experiences in mind to help me get it to actually run. It has a sliding valve cam operated, but I think the piston type valve is a better idea, and will be using iron for cylinder, piston and valve, rather than the ali specified. I'm really looking forward to your post saying it runs as long as you want, and its a go.
I'm an engine rebuilder as a job, I work on old and antique engines, mostly motorcycles, but tractors and farm equipment, having a shop out in the country surrounded by woods and fields of farms. This is my first ever post on any forum, as I am rather new with the internet other than reading news and finding parts and material for projects.
Mad Jack
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Hi Nick
Cracking job with that engine I bet you're really chuffed.
:clap: :clap: :clap: :clap: :clap: :clap:
I've filed away your experiences with this engine for when I get round to building one, thanks for passing on the info.
Have fun
Stew
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That`s great Nick! :clap:
So very pleased for you...... Also that my "two pennorth", helped a little..... :thumbup:
David D
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Mad Jack,
Thanks for the interest and comments. The engine does run until the fuel runs out now. The oil used on mine actually helps keep any deposits from unburnt parts of the fuel building up and causing excess friction. I am going to try a run with it completely dry once again with the new, purer alcohol though. It will run faster without the oil but probably not for as long. The designer of the 'poppin' engine I keep talking about swears by oil and he has a constant drip feed on that design which works well, however, others say they don't run with oil. From my experiences, my engine seems to prefer running with oil. I guess a lot of this depends on clearances of individual engines though and it's the balance between making a good seal and keeping friction down.
I think cast iron is a good way to go though becaue of the self lubricating properties. I don't necessarily think the piston valve is better. In my opinion it's easier to get two surfaces flat and smooth than two as near cylindrical and round and smooth as possible. The little 'poppin' design uses a very thin spring steel valve which because of its flexibility seats very well, especially as the vacuum starts to pull it against the port face. It also means very very low friction and hence a very small amount of force to drive it. This takes the criticality straight out of the valve and means you only need to get a flat port face, which is easy just lapping on a surface plate and a bit of emery. Those are just my opinions based on experience during this build anyway. I might yet build the poppin as an exercise more than anything to see the different characteristics of the two types of engine, afterall, I already have all the materials now!
Your work sounds very interesting we'd love to see some of that posted on here! I was into stationary engines and the like when I was a teenager, which is probably what got me interested in this hobby.
Stew, David, Wes and Gerhard - thanks very much! Chuffed is an understatement - there were times when I thought it was not going to show any sign of life! :thumbup:
Nick
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Thanks for the nice welcome to the forum, and I'm glad to know your engine is running completely now, I think you are exactly right in that some engines like oil, and some won't tolerate it at all, and it is frequently little things which determine the outcome.
I have to say how much I enjoy the forum if for no other reason than seeing a different attitude among those who are from a different country, and have differing resources. I have a radial engine I bought plans for a year or so ago, which I made good progress on for a while, and got side-tracked by work, and seeing the pictures and reading the posts has re-motivated me, I've got back to work on it, and will be posting pictures of it soon. I have to learn how to use the forum, as in how to put pictures in, and the like, as it is entirely new to me, and a challenge. I will get pics of what I've got done posted in the next few days, and get this engine running as soon as I get the thousand parts or so made. It is a scale model of a nine cylinder Pratt and Whitney radial of about eight cubic inches.
Thanks much, Mad Jack
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No problem Mad Jack. To let you in on a little secret, we all get side tracked at some point, well I do quite often anyway! I was into this hobby before I started university and it took around 8 years for me to get started back up in it, it took a couple of years to get sort of up to speed, I was a bit rusty on basic skills and I knew an awful lot less than I thought I did! I still grossly underestimate the time and effort it takes to make things and don't allow enough contingency plans! I originally took a weeks leave to do this and got side tracked rehashing the bedroom - 2 months later and it's working!
There are plenty of people to help out on the IT side of things.
Wow, the radial engine will be an impressive model. If my grandad was still with us he would have loved to see it. He used to rebuild them during the war, remember him telling me the stories of them washing parts down in baths of trichlorethylene - nice and healthy!
Nick