Another Simple Hot Air Engine

[Sanjay F]

Coming along nicely ...... it looks like a piece of modern art which should be in the window of an expensive London gallery! 

[PaulR]

Hopefully it won't end up as just an ornament!

[PaulR]

Made the little block to go at the top of the displacer rod, there will be two flat rods either side going up to the crank pin with the piston rod sitting between.

Made a piston from some reclaimed cast iron but somehow managed to take too much off - it would probably be fine for a compressor powered engine but not good enough for a hot air jobbie. Also as it would be difficult to get the small cross hole properly centred afterwards, I made another one from some aluminium rectangular bar which I drilled first for the wrist pin then turn down very carefully. The fit is rather good.

Next I made the aluminium piston rod from some recycled garden furniture (I could probably make a thousand of those from the masses of square tube I salvaged). Drilled the holes at the right distance then filed it to shape using filing buttons for the larger end.

[PaulR]

Made some more bits, just a pair of simple link rods and a flywheel needed and that'll be the engine itself finished. Other than that I need to make some legs with a way to hold the 'heat shield' and probably another burner as the others I have are too weedy.

I'm still thinking there are too many places for a bad seal to stop this from working at all. But if that does happen, I can bypass those issues fairly easily by soldering a tube between the (un)plugged hole and the back of the power cylinder but it'll mean the bits can't then be disassembled.

[PaulR]

That's most of the bits done, just need to connect them together with some proper fasteners and make a crank pin etc.