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Steam Engines? Answered

I am wanting to make a small solar steam engine and am wondering what pressures they run off of usualy? Can you power a pneumatic drill or grinder with steam and use it as a steam turbine? How do people make small boilers to power the steam engines? I was thinking a peice of copper, iron, or galvanized pipe. I would heat it with a fresnel lens from a rear projection tv. Can the spot from a fresnel lens me further focused with a normal glass magnification glass?


Models as little as 3 or 4 PSI HOWEVER to get that you have to be good and very accurate - More normal is perhaps 10 to 20 PSI

You might be better off with a stirling engine built from a kit of parts

Is "dry" or superheated steam ever used? I was thinking the pressures would be around 200psi or so because copper tubing can take up 500 psi.

Not for small engines, as far as I know. High pressure steam is dangerous stuff.

Would it be possible to convert a pneumatic tool to run on steam, like a drill or grinder? Aren't they turbines? Would you have to do anything?

I tried it with some success. I have a 5' mylar tape covered parabolic dish for cooking on (and experiments) that I bought online. I also have some extra solar water heater panels. So I ran water very slowly through 2 4' x 8' solar panels then to copper tubing that I bent in a coil about 5" in diameter. I used a brass fitting to connect that directly to a pneumatic die grinder with the trigger wired on (I didn't want to build up dangerous amounts of steam pressure). I was able to get the die grinder spinning at a pretty good rpm.

My ultimate plan is to use an air impact driver which has a speed more appropriate to spin a car alternator (around 6 or 7k rpms). They take about 4 cfm at 90 psi. Instead of the coil of copper tubing which really didn't capture all the beam from the dish I'll change to a short piece of steel pipe with copper tuning in and out of it.

I'd like a spring-loaded piston connected to that steam chamber to pull the impact driver trigger when the pressure gets up to some adjustable psi.
I'm thinking of using 1 or more mister nozzles like we use here in Texas to cool us off on the inlet into the steam chamber to control the flow of water in. We have 90 psi water at our house so I'm pretty sure water will still go in if I get the pressure up around 70 or 80 psi.

How long will the impact driver hold up to running steam? Who knows? But they're cheap at Harbor Freight.

I "hoping" I can produce 4 cfm of 80 psi steam and that that would drive a 100 Amp alternator, but we'll see. I'll post a video at some point.

WARNING: Most plastic hoses will easily burst when carrying steam even at low pressures. I learned that the hard way. Very painful. Be CAREFUL with STEAM!

In theory, yes.

In practice, pneumatic air sources usually make an effort to filter _OUT_ moisture, which I think is sufficient evidence that the tools would be significantly unhappy if you did this to them.

Also, you'd have to think about where the tool's exhaust is located and whether the escaping steam would parboil your hands or the piece you were working on.

So in practice, I think the answer is no.

I wasn't thinking of using it as a pneumatic tool and was just thinking of using it as a steam turbine. I think alot of them are cast aluminum so steam might work ok?

I watched a program on tv concerning a man who builds small steam engines. He cautioned everyone that high TEMPERATURE steam can kill you with one breath. A cloud of hot- steam can be many hundreds of degrees hot and it is invisible and odorless. One breath of it into your lungs will burn your lungs. So if you fool with steam be sure you research the subject and build safely. He also mentioned there are several types of boilers. some of them are prone to explode easily, others less likely. Be sure to build the less likely one. He mentioned that the "steam" you see coming out of a tea kettle is NOT REALLY steam... he called it water vapor and it is "ONLY" about 200 degrees hot. Steam can be MUCH hotter.

As far as I am aware, the only steam engines that run off solar power are very large scale, using fields full of mirrors to focus sunlight onto steam boilers.

If you want to use solar on a small scale, go with a sterling engine, as others have said, or something akin to a Wonder Wheel.


this man has done it - Better run a compressor from the steam, the moisture would probably screw up the tools that are intended to run on dry air.<p> High pressure steam is a killer - Your estimate of the pressure copper tube can stand displays a very simple view of a VERY complex and dangerous process. Much depends on the tube, wall thickness, construction methods etc.