MM01 - The OPITEC engine

The engine was built from a kit sold by Opitec. I made several modifications:
The displacer cylinder was originally designed to be made of a stainless steel tube with a brazed-on copper cap; I used a segment cut off from an N₂O whipping cream cartridge instead and a test tube as displacer piston. For lower friction and a tighter seal, I replaced the original displacer piston rod by a shaft liberated from an electric motor running in sintered bronze bushings cemented into the heatsink with two-component adhesive. Opitec included this same type of friction bearing into their later version of the kit. Aiming to minimize frictional resistance, I supported the crankshaft with two ball bearings from an old hard dive instead of brass bushings. All these changes were fundamental for making the engine finally run -- it now runs so well that I have to think about balancing the flywheels...
Further information on the new kit can be found on R. Fackiner's homepage: http://ast-ra.de/opi/Motorenbau_/Der_OPITEC/der_opitec.html