Hot Air engine

[boiss]

A few years ago Itried to make a hot air engine, without a great deal of success.
My problem was the friction between the cylinder and piston. I tried various things but they all failed. I believe that the originals used a glass cylinder and a graphite piston. I'll post some pics of mine tomorrow weather permitting.
Mike

[jimmc101]

Fascinating devices, I've just bought one of these http://www.banggood.com/Low-Temperature-...74187.html,.
The power piston is some form of plastic running in a glass cylinder.
It runs surprisingly well apart from a bit of knocking from the big-ends which are 'C' shaped and just clip over the journals.
The engine is shipped without he flywheel / crankshaft fitted, assembly consists of springing the pointed ends between the supports and clipping on the con-rods.

There's a nice explanation of the principle here... http://www.youtube.com/watch?v=Rd7nLOEsqj8.
(Beware 'Sixty Symbols can be addictive!)

Jim

[Alan Douglas]

I made one as a kid, using copper cans from electrolytic capacitors. It took quite a temperature differential to make it run, as you can tell from the blowtorch blackening of the outer can, and a water jacket around the other end. But it did work.
   

[AlanBeckett]

You can even get a Cardboard one - http://www.astromediashop.co.uk/Other_kits.html
About half way down.

Alan