Two 'Wobbler's' for presents!

[mklotz]

I've often fantasized about the possibility of building an engine that would run off an inflated party balloon as an attention getter for my middle school lectures as well as a means of showing the kids how the engine "consumes" air as it operates.

My miniature, breath-powered engine will run off a well-inflated balloon for a few seconds but it doesn't have the "impression factor" that I'm looking for.

Has anyone ever built an engine that will run off a party balloon for, say, thirty seconds?

 

[rickharris]

not for long but my father used to demo a Mamod traction engine by putting a baloon over the boiler filler

 

[stevehuckss396]

Very nice job. I also built 2 of these same engines. Mine do not look as good as yours. Beautiful work. I made one full size and another in 1/4 scale.

 

[shred]

I ran across a web site somewhere that said balloons are only at about 0.3 PSI (makes sense, we can hardly blow more than 1-2 psi). So, I'm guessing a very low-friction motor is the key. I wonder if the LTD Sterling-type motors could be adapted easily.