I have enjoyed making Hot Air (Stirling) engines out of Tin cans here is my latest it is made from plans at http://www.boydhouse.com/darryl/stirling/index.html , a simpler one can be made form plans at http://www.bekkoame.ne.jp/~khirata/english/mk_can.htm If you know of any other good plans please let me know.
I made my piston from" J B Weld " which is available from Halfords.
I also used a VCR video head as a Bearing for the Crank/Flywheel.
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