Air power for stationary engines.

[Reabo]

Hi, I am totally new to steam models so have probably a really basic question. I want to build a grasshopper beam engine, what I want to know is can this be powered by compressed air or do I need a boiler? If I need a boiler will Tubal Cain's Polly or Elizabeth boiler be enough or will I need something bigger? I want to build the engine first, get it running then build the boiler. I have the skills to do the machining, building etc but not the knowledge for model steam engines/boilers.

 

[kf2qd]

They will run on compressed air. Most are actually designed to run on compressed air.

 

[pat_pending]

Hi, Reabo, I have built a couple of Elmer's wobblers (a #25 and an H-Twin were my first ever engines! when I was starting out) I ran them on air and it worked great. In the end I was lucky enough to get my hands on an airbrush compressor which was absolutely ideal for the task as it was near silent and had plenty of puff to run the models (I think the compressor innards come from a refrigerator so are all inside an oil bath for sound proofing). I highly recommend.

-Patrick

 

[pat_pending]

Hi, Reabo, I have built a couple of Elmer's wobblers (a #25 and an H-Twin were my first ever engines! when I was starting out) I ran them on air and it worked great. In the end I was lucky enough to get my hands on an airbrush compressor which was absolutely ideal for the task as it was near silent and had plenty of puff to run the models (I think the compressor innards come from a refrigerator so are all inside an oil bath for sound proofing). I highly recommend.

-Patrick

Actually, depending on the scale you might need a compressor can pump a bit more volume. The Grasshopper seems a lot bigger than the small Elmers wobblers

 

[Jasonb]

It would need to be quite a small grasshopper to run off a Polly boiler, although the pressure does not need to be high if not running under load you will need a fair volume of steam for a reasonably sized engine. This is my grasshopper running on air, its a doubled up version of Anthony Mounts design

 

[Reabo]

Thanks for the replies guys. I have a compressor in the workshop which goes thru a regulator so have plenty of air supply at low pressure. May do a bit more research on boilers before the build, but got to build the engine yet. I was looking through the plans on this site and found some CAD drawings for Gerry's beam engine which looks good, might be tempted.
Jasonb that looks lovely, an aspiration and an inspiration.

 

[kwoodhands]

I have built Elmers Grasshopper beam engine. I run this engine and all my engines on air. I have run two wobblers on steam, usually I run these on air.
I have run 6 engines at the same time on air with a manifold.
Tried more than six but my compressor is a 30 gallon tank and could not keep up with more than 6 at a time.
mike

 

[davidyat]

Reabo, all my "steam" engines have the male air compressor fitting installed that matches the female air fitting from my compressor. I just put an on/off fitting in-between and away I go.
Grasshopper

 

[metalmangler]

I've successfully run a Reeves 'Lady Stephanie' (no load) on the boiler from Tubal Cain's 'Hercules' steam-crane, so you don't need that big a boiler as long as you don't want it to do any real work.

 

[Reabo]

Thanks for that. It won't be doing any work just running for my pleasure.
And that is a nice looking engine. There seems to be s many beam engine to make I may have to give up building motorcycles. Lol.