The cylinder heated by a candle is a pipe stuffed with aluminum foil which was hammered flat to get the best seal possible. The CDs prominently featured on the final product act as the fly-wheel. To ensure that there is enough mass [Jam] ganged three of them together. There is also a counter-weight affixed just off-center to help keep the wheel turning. The gears shown above were actually used more like mounting plates to build a cam. Looking at the body and frame of the device makes us wonder how in the heck this thing actually came together?