Dennis, here is another interruption. A friend gave me an old oil-less air compressor that runs perfectly. After taking it apart I found that the fiber ring was almost disintegrated and the one piece piston connecting rod had damaged the cylinder. I made a new ring out of brass just to see if it would work. As expected the heat welded the brass to the damaged part of the cylinder. I decided to experiment to see if I could modify it to a movable piston made of UHMW plastic. Have not finished yet. I do not think it will handle the stress of the weight of the new parts. There is a new picture of "firing pins that work" on the yahoo group. I have asked the gentleman to email me any information