Introduction

[wsippola]

Hi, been lurking here for a while getting info for a boiler I will be building. If the photo has attached properly, you will see a straw burning American Able with the youngster beside the drive wheel being my Grandfather. The photo was taken in 1917 in SW Saskatchewan. I've been building a 1:14 scale version for the last year or so. Wheels and engine are mostly done. Planning a copper boiler of 2" L type tubing for the barrel. I have 660 bronze for bushings and was planning on using bronze tig rods (I believe silcon bronze, but not sure) for stays. All silver soldered of course. Making a few 00-90 hex bolts tonight out of 3/32 bronze rod.

Something that you might find of interest is a "boiler" I made for destructive testing. Just scrap 2" tubing (thinner stuff for vents) with some flanged 1/16 copper ends, a single 3/8 tube through the center and a single bush in the "barrel." Pumped it up with a grease gun and oil to 500 Lbs. No leaks, no rupture, but of course it bulged in all the areas you would expect. I thought it was a nice confidence booster. Did it close to ayear ago, but if you want a picture, I believe I have one.

Well it sure is nice to have access to such a lot of experience in the live steam hobby. I have had little to do with live steam other than building a couple of small stationary engines of no particular merit, along with a couple of sterling engines. Been doing metal working as a hobby now for over 20 yrs, but the little Abell is my first foray into real live steam. I certainly would appreciate any comment on choice of materials for the boiler stays etc and look forward to joining in here. Thanks,

Wayne


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[sncf141r]

Hi Wayne;

You know, steam tractors/rollers/traction engines (take your pick) are interesting. A club member here has a "Minnie" which I think is 1:16, and another is building a 1/4" case 65hp, almost completed. (might be 1/3?? I should know...)

Copper boilers are neat, and, as you know, are quite strong. Do you have boiler codes for planning your boiler? There are the Australian ones, and Kozo does a good job in one of his books.

Welcome to the list; JohnS.

Hi, been lurking here for a while getting info for a boiler I will be building. If the photo has attached properly, you will see a straw burning American Able with the youngster beside the drive wheel being my Grandfather. The photo was taken in 1917 in SW Saskatchewan. I've been building a 1:14 scale version for the last year or so. Wheels and engine are mostly done. Planning a copper boiler of 2" L type tubing for the barrel. I have 660 bronze for bushings and was planning on using bronze tig rods (I believe silcon bronze, but not sure) for stays. All silver soldered of course. Making a few 00-90 hex bolts tonight out of 3/32 bronze rod.

Something that you might find of interest is a "boiler" I made for destructive testing. Just scrap 2" tubing (thinner stuff for vents) with some flanged 1/16 copper ends, a single 3/8 tube through the center and a single bush in the "barrel." Pumped it up with a grease gun and oil to 500 Lbs. No leaks, no rupture, but of course it bulged in all the areas you would expect. I thought it was a nice confidence booster. Did it close to ayear ago, but if you want a picture, I believe I have one.

Well it sure is nice to have access to such a lot of experience in the live steam hobby. I have had little to do with live steam other than building a couple of small stationary engines of no particular merit, along with a couple of sterling engines. Been doing metal working as a hobby now for over 20 yrs, but the little Abell is my first foray into real live steam. I certainly would appreciate any comment on choice of materials for the boiler stays etc and look forward to joining in here. Thanks,

Wayne


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[alanstepney]

Copper boilers are easy to make, and, provided they are made correctly, very reliable.
I have one that I built over 40 years ago, and although I am now replacing it, it still passes the annual test, so they also last well.

The stays are best made from copper, although monel metal used to be advised.

I wont comment on using TIG rods as I dont know the chemical constituents.

[wsippola]

John,

I have found the formulas for thicknesses and stay spacings for model boiler design on the web (might have been this sight). I was thinking about building it very similar to the original straw burner which has a funky air chamber above the fire, just below the level of the tubes to help burn the straw gasses. Certainly won't make it work better in model size not to mention it would make it a fair bit more complicated to build. I think I might just stick to a plain boiler design.

Alan,

Well I'm not stuck on any particular design for the boiler yet. I figured the bronze stays would be stronger than straight copper. Is the appropriate thickness of copper electrical wire suitable for stays? Seems too soft. The web sight on the tig rod package just lists the rod as copper / tin alloy. It does have a phone number for technical information, which I will try. The plan is to use all brass / bronze / copper / stainless for the engine, as I want it to last. I'll post a photo of what I have built so far one of these days, but it's out in the shop which is across several snow banks and it's quite cold our right now!

Wayne

[Bill Shields]

I have a semi-finished copper boiler, TIG assembled as much as can be welded, by a guy that really knows how.

It's a very valid way of doing things, provided you have the correct copper to start with and filler rod.

If you TIG the stays, they will have to be pure copper.

[Jan]

I have a semi-finished copper boiler, TIG assembled as much as can be welded, by a guy that really knows how.

It's a very valid way of doing things, provided you have the correct copper to start with and filler rod.

If you TIG the stays, they will have to be pure copper.

Have helped freinds to TIG welded theirs Copper boilers, I cut square strips from same sheet that the Boiler are made from,
and use them as filler rods. Jan.

[Harold_V]

I would think solid copper wire could be used for filler. Because of its intended purpose, it is made from electrolytic pure copper.

Is there a reason it doesn't work that is known by any of the readers?

Harold

[Kimball McGinley]

The wire is probably dead soft for flexibility. Rivets would be better, I think, as they have probably been cold-worked to some degree of hardness. If the rivets are silver-soldered with 45% solder, they will end up annealed anyway, ending up the same as the wire.

[Harold_V]

I agree on the flexibility of wire--cold working might be desirable. That issue aside, seems to me it should work adequately.

Harold

[Bill Shields]

The folks that do this for a living say that oxygen free copper should be used for filler, and that copper sheet, containing any arsenic should be avoided at all costs.

Arsenic is commonly used in the copper smelting process...but doesn't have to be.

Either of these situations would / might preclude using the base material for filler.

[wsippola]

Good discussion on using the electrical wire for TIG filler. I'm not however tig'ing the boiler, it will be silver soldered. Getting practice with that while building up my components like the engine parts. My original intention was to use bronze rod for stays, and the easiest place to get the bronze rod is tig filler rod. That being said, copper wire is also easy to get - I just hadn't thought of it as the best stay material. I used copper wire for the rivets on the grouter bars on my wheels. Dead soft, but I expect any copper used for the stays will end up that way after silver soldering.

Unfortunately the grouter bars I made are not particularly to my liking. They should have a more pronounced taper to them. I actually tried to set up a wheel on a dividing head and trim the grouter bars in place. It worked to a fashion, but was very slow and a royal PITA. I suspect I will eventually go back and replace the 104 bars with better detailed ones. Maybe I'll just live with them.