French Beam Engine

[doubletop]

It's time to start my own topic over here, and give the rest of us have something new to look at while the Brits spend their weekend at the Harrogate show.

This isn't going to be a blow by blow account of what I'm doing as its more about me improving my skills rather than a 'how to'.

As with most of these projects, the start is governed by what materials may be to hand. Some months ago I stumbled across this lump of bronze in the scrap yard.



The flange was an odd shape, wouldn't fit my little mechanical hacksaw, and hand cutting it was way too slow. So I tried a slitting saw in the mill. To start with all went well and I got the lump into more manageable chunks. At the time I had in mind doing Bogs Paddleduck, so was aiming to get two cylinder blocks out of it by way of a start.



Inevitability disaster struck, so it was back to the hand hacksaw.



(OK lesson learned #1, use the right tools for the job.)

Some months passed; having spent the best part of 9 months working on my locomotive, that's now working pretty well, so on to something else. I have a copy of the plans for a beam engine from this French website http://jpduval.free.fr/. I've done his twin oscillator vertical marine engine and the quality of this guys plans is excellent so had no trouble in deciding to do another of his engines. I have no French but sites like Bablefish come in handy if there's something I don't understand.



I started off with the cylinder, no idea why, but to me it's the obvious starting point. The plans imply machining the cylinder from solid, I didn't do that and preferred to fabricate from two parts.

The cylinder was another piece of scrap bronze I picked up from one of the guys in the club. It already had a 10mm hole through the middle so was just a case finishing the outside and running the boring bar through it out to 15.8 mm ready for the reamer later. (no pics)

The valve block was a chunk of bronze from the big flange (above) and I used the arc function on the DRO on my mill to form the seat for the cylinder



The two parts fitted together quite nicely ready for silver soldering later



Next part was the valve chest. Another lump of that flange attacked with the home made fly cutter



And a nice shinny block to work with



That's it for now, more later...............

Pete

[saw]

Hi, this should be intressting, good work 

[Imagineering]

Looking good so far Pete,

(from the other guy in the club) 

[Bogstandard]

Pete,

Please be careful with those plans, and don't show too much. They are not the free ones from that site, those ones with a few others are copyrighted, and you have to buy them.

They do make into very nice models BTW, very elegant looking.


John

[doubletop]

Guys

Thanks for the concern; I'm very much aware of IP issues whether the documents are marked or not, and only posted a copy of what is already available on the website here http://jpduval.free.fr/Liste%20des%20plans/Liste_dossiers_plans.html. In particular http://jpduval.free.fr/Liste%20des%20plans/mv%2016x32%20bal2.pdf ( I can happily replace the .jpg with a link to the .pdf if the moderators wish)

That said I'd recommend going over to the site and taking a look around, OK its all in French but pictures paint a thousand words and there's plenty there to whet your appetite.

Pete

[Bogstandard]

Peter,

I do know that the drawing shown is in the public domain, I was just raising concern about the rest of the plans for that engine.

I also scan that site a lot, in fact, one of the engines that I used to make as a commercial undertaking is very loosely based on one of their free plans, I just made it a lot better.

I personally have purchased all the plansets that interested me on that site, and I can say that they are well worth buying. They really do make up into nice models, in fact John Somers has made the sister version of the one you have just started. I know that because I made the flywheel for it. In fact, I turned it into a bit of a teaching post.

http://madmodder.net/index.php?topic=871.0


John

[websterz]

French Beam Engine? Where does the white flag go?

[doubletop]

John

All's well; I had no intention of publishing the plans, that's why I pointed people over to the French site. As you say they are well worth buying and the guy deserves a plug. As you know I've made the twin oscillator as well and was very pleased with it. I took the view this one should be equally as good.

websterz

Not sure which version of history you are alluding to but if a flag is required I'm sure those requiring one could work out where to put it.

Anyway preamble over, let's get on with the build..........

Pete

[doubletop]

This project has been moving on a bit since I started around 7th May, about 10 days ago.

Silver soldering of the cylinder and ‘saddle’ I placed the fluxed saddle in the hearth with three pieces of silver solder  sandwiched between it and the cylinder, cylinder on top. Heating it up the solder melted and the cylinder settled into place.

There was a hairline crack at the ends so rather than risk it I re-soldered the ends by placing 3 small nuggets of solder in flux on the ends and re-heated. One end at a time.

After the pickle, a quick blast in the sand blaster to give it that casting look.



As you can see its been reamed and all the holes and ports drilled and milled. I’m quite pleased with the way it turned out. As Bogs can attest I struggled with soldering this time last year.

Next was all the bits that bolt onto it.



And loosely assembled



Next came the base plate. This was just a mark out, clamp to the mill table  and mill/drill as required. As I’ve said I have DRO’s on my mill but I still took the time to mark it out as a second check that everything was where it should be. The DRO’s make the job relatively easy as you can always get back to any point. The DRO rectangle function helped with getting the three slots finished although I freehand roughed them out first up close to my marked out lines



The standoffs were a quickish job now I have worked out how to easily setup a backstop on my lathe.  I realized that I can install collets in the nose and fit the chuck over the top. So with the ¼” collet and a suitable length of rod I have my backstop. OK somebody is going to tell me you all do that, so do I now.

Cylinder assembly in place



Next was the bearing blocks, relatively simple and done before morning tea today



Now on to the flywheel. This is another donated piece of scrap from Murray (Imagineering). It was a dirty black ring when I was given it and in a quiet moment had stuck it in the lathe to see what I had.



Clearly it was destined to be a flywheel for something, now is it's time.

Serendipity applies from time to time in this game and I just happened to have some 64mm dia ally and the hole in the ring was around 63mm.



It didn’t take long to get it down to a nice fit  with the intent of loctite’ing it in when ready. The next job is to machine some spokes. If that doesn’t work I may resort to a hub and silver steel spokes. I’ve seen both done on the forums



That’s it for now;  because  you have 10 days compressed into 2, things will slow down a bit from now on.

Pete

[DaveH]

Pete,

Looking rather splendid

Like the look of the flywheel.

DaveH

Edit - finger trouble!

[saw]

Very nice build 

[doubletop]

Thanks Dave, Saw, Murray (and apologies for not acknowledging previously).

I went on the search for a flywheel 'How to' which I thought I'd seen on HMES only to be redirected over here to a Bogs post on the subject which uses the same engine flywheel as an example. http://madmodder.net/index.php?PHPSESSID=282779f14615aa033c7f5d9e8cca14a2&topic=871.0

I haven't read it through yet but do recall his preference for collet mounting, which means I may have to comply.

Pete

[Imagineering]

Looks like you've caught 
At the rate you are progressing Pete, you'll have it up & running before the next Club Meeting.

Murray.

[doubletop]

Thanks Murray

I don't think I'll get that far and its not about trying meet any particular deadline. However, I find the "eating an elephant analogy" works for me. Focus on the part being made one at a time, work out the plan of attack, do your best and then move on to the next. If you go wrong work out a recovery strategy or start again.

There is an example here



The plans have the base tapped 4mm for studs for the stand offs. I'm using BA throughout and ended up drilling 4BA clearance with the intent of using bolts, I then found the bolt heads would get in the way of the cylinder. I had a number of recovery strategies, including start again. The drawings require some of the other holes to be counter bored so I counter bored these holes and then turned the heads down on some 4BA cheese head screws. I think its now neater than the original not having stud ends peeping out of the holes.

So having a pile of half completed parts is just fooling yourself you aren't a production line and its unlikely that your workshop is equipped to have a number of things on the go at the same time. Of course 'bling' is done at the end, repeated assembly dis-assembly while fitting parts will just mess them up so they have to be blinged again.

Doing it this way means you progressively get to the end. I think this model has different 45 parts I think I've done about 12 so just over a quarter of the way through.

Pete

[doubletop]

Armed with a copy of the relevant bits Johns "Making a flywheel" post I headed to the workshop. It was all pretty painless really and I was pleased with how it went. However, I had formed the shape of the disk too deep and the 8 mm drill wandered off on the outer ring on one side of the spokes. I pressed on to the end by way of making it a test piece/prototype to prove it was what I wanted






A new blank was hacked off tonight ready to do another one tomorrow.......

Pete

[Bogstandard]

Don't worry Pete, excellent first try.

What you have to realise, I have been making them for a long time, and know a lot of the pitfalls, but even so, I still make mistakes, and have to 'modify' on the run to get them looking OK. It is knowing how to rescue when they do go wrong that is the secret.


John

[doubletop]

Thanks John; it went pretty well really and your instructions helped immensely. It was also helped with me using the same DRO and making a version of the same flywheel as in your example, albeit with a smaller outer diameter. So it really was a case of do what it says on the box.

I did notice one small anomaly with your instructions that comes about with making a smaller diameter using the large 8mm radius fillet. When setting the X offset for the spokes on the outer diameter the offset moves tangentially to the PCD. As I only wanted a thin outer ring I had to compensate by reducing the Y slightly. I didn't do the maths and just reduced Y 'a bit'. You can see that in an extreme case of a large radius fillets, thick spokes and a thin outer wall moving Y to the PCD - fillet radii and X to 1/2 spoke width - fillet radii you could end up drilling outside the outer diameter. (hope you follow that?)

Thanks again

Pete

[DaveH]

Pete,

I think thats a pretty good flywheel 

It could be rescued - on the fly so to speak        (on the fly)

But there again I'm a lazy o' sod 

DaveH

[doubletop]

Dave

I thought of trying to rescue it but opted for completing it as it was to see if there were any other pitfalls. The fact is John instructions are so easy to follow that doing another one, and getting it right, is good training for all the others I may need to make in the future.

Pete

[Imagineering]

. . . is good training for all the others I may need to make in the future.

Pete

Does that mean we will see more than one new Engine at the next Meet

Murray.

[madjackghengis]

Hi Pete, I guess I missed this build till now, but I'll chime in with my two no make that about half a cent worth, we keep printing funny money and it's hard to get two cents together these days here:  I suspect you ran into a piece of aluminum bronze in that flange, from the damage done to the slitting saw, keep the pieces and cherish them, it is good material to make strong things from, even if it's hard as a witch's heart, and it keeps its shine a long time too.  I suspect I should have bought a more expensive DRO, because I keep reading about arc functions and rectangle functions, and mine has none of that, just bolt circles(PCD) and straight line bolt hole functions.  That arc function, if I read it right, lets you mill an arc in a piece of stock that a cylinder will drop in I am guessing? The rectangle function lets you set up corners and stay within the lines, or am I reading too much into it, as I do rectangles by choosing a corner, milling to the next, changing directions and milling to the next, and so on down through a piece of stock or plate?  All in all, you've got a very nice build going forward and I think it will really shine with the bronze and aluminum setting each other off.  I look forward to seeing it with all the rods, beam and connections in place and ready to put steam to her.  Great job so far.    Cheers, Jack

[DaveH]

Good one Pete

DaveH

[doubletop]

Murray

Yes there will be more than one engine at the next club meeting, yours and mine. Regardless of their state of completion. We should also take along the warts to demonstrate its not all plain sailing. My wonky flywheel and your toothless gears come to mind...........

Jack

I did a bit of research on DRO's before I purchased, there are expensive like Newall and Easson and the cheaper Chinese versions such as Sinpo and Sino (there are plenty of others) In the end I went for Sino on the simple differentiation that if they are OK for the Bogmeister they will be fine for me. Later investigation showed that the manual content for Sino and Sinpo is virtually the same indicating to me the controller electronics is the same. It then comes down to the scales which the seem to be differentiated by the number of seals they have. As they are offered on the basis of "the price is the same how long do you want them?" they are much of a muchness. OK its impossible to do the true technical spec assessment MTBF, EMC, IPxx etc etc it becomes a case of you pays your money and take the chance or buy Newall or Easson.

On the functions; as well as the PCD function it has

Smooth “R”  - which allows concave or convex curves to be milled in either the XY, XZ or YZ axis. The YZ mode is what I used to make the 'saddle" it was a bit tedious as it required 250 steps as it incrementally to mill the shape along the X axis

Internal rectangle  - This progressive give the coordinates to mill a pocket in a workpiece as it works you from the center of the shape outwards. External rectangles are just a standard milling function. I used this for the valve chest and base plate

Mid-split - Use edge finder to find the one end of the workpiece, zero the axis, use edge find to find the opposite edge. do mid split and you have the coord for the center on that axis. No need to compensate for edge finder dia. I used this to center the mill on job in the round table, when finding say the x axis I move the Y backwards and forwards slowly to ensure I find the peak of the circular job. Although doing this may not be unnecessary as the perpendicular of the center of any tangent passes through the center of the circle. The experts can put me right on the accuracy of doing it this way compared to an expensive centre finder.

Divide holes on an oblique line - like PCD but a line of holes at an angle, I've only used this to set my 4"  machine vice at the correct angle by setting it to do two holes at an angle at 4" centres and using the DTI in the chuck to ensure the vice is set correctly. It may be the way of setting up to do the relief in the beam later.

There are a few other things in the box but these are the most useful.

Hope that helps

Pete

[doubletop]

Dave

Apologies I missed acknowledging you; Thanks for the support

Jack

If that's aluminum bronze its certainly nice stuff it even comes out of the mechanical hacksaw with a shine.



Today was another go at the flywheel. This time I started with a flat blank so the drill wouldn't go walkabout.

Drilling completed



Final cut done



Actually this is my third attempt the blank I did last night was a scrapper before it got to the mill it was undersized for the outer ring. All three efforts below. You'll see this time I reduced the spoke thickness after the milling. I'm very happy with the result.



It just needs blending, the bush making, fitting to the outer ring and the whole thing skimmed up.

Pete

[saw]

Very nice build, good work