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Just to show what I'm working on -- a couple of small steam engines made from mostly pipe. Not done yet, but this is where they are now. I have started 4 engines actually but these are the most finished so far. I keep getting new ideas of what I could do differently, and then start another one to try it out.

[Image: PipeSteamEngines.jpg]
Nice little engines there vstream.

If that's galvanized pipe, I hope you're aware of the hazards of welding/brazing that stuff.


Ed, It was black steel pipe - actually rusty steel pipe!

I do weld and/or braze galvanized metal after stripping it in dilute muriatic acid. In fact I strip black steel pipe as well. Otherwise it doesn't braze well. And certainly strip rusty stock!

Brass brazing rod contains zinc, btw. About 40% in order to lower melting point in relation to most brass and even copper, which is often brazed. It's important not to overheat while brazing not only for fume control, but for soundness of joint. I braze outdoors, and take precautions. You can braze with pure copper, too.

ps. the bearing boss on the twin was a piece of brass rod that was brazed onto the steel, as an experiment. Temperature control is important when trying that, since the melting points of the braze and part are close.


Interseting design Steve Smiley-signs107
Whats the valve arangment ?

Hi Rob, on the twin it was intended to be bash valve with stainless ball (you can see the chamber in the heads -- screws are temporary --another upper head layer will be added to take the steam inlet and form the stop. The exhaust will be uniflow ports. This was the simplest valve actuating combination possible. I wanted to try very simple pipe based engines to go with my pipe boiler. The square end plate was left that way while building to serve as an index for machining operations -- intent was to cut it back to round and fit side bearers when finished. It could be be retained as a radial mount plate, but probably not.

I decided half way through making the twin that I also wanted to try out piston valve engines, and finding that 3/16" rod was a good sliding fit in 1/4" copper tube, thought I'd try another rapid build variation on the pipe theme. So the single was put together as a quick and dirty test of that. It has an internal cam on the crankshaft, which I thought would be kinda cool with an external valve guide. Also intended as a uniflow exhaust. Shooting for 20% clearance volume to lower pressure requirements, since there's no auxiliary exhaust valve.

I've wanted to see how far I could mimic the look of early motor bicycle engines -- depending on which valve arrangement I liked best, the ultimate aim being casting better shaped crankcases which would look decent . Still these aren't too bad looking as "functional" test pieces -- the single has a sort of steam punk quality I'm kinda warming to. Needs much more to complete, including bearings (though oddly the steel on steel plate now spins easier then the steel in twin's brass bearings). Same for the twin, it's just a work in progress at this point.