Hi Petertha and thanks for your words, I read like 10 times the Tribmle method, very difficult for me to understand all the numbers and calculations,(I´m a doctdor!) so, I had the opportunity to visit my friend Roy Sholl (S/S Machine & Engineering LLC) workshop, he is an expert, and he made the calculations for me, we machined a few in his place, and he calculated the gap pin diameter for me, I did the tempering operation in the lathe with the OA for testing, some days later I got the little furnace, and took them to 1200 F for 20 minutes, then to 900 F for 10 more minutes before cool down, I had an extra .010 in. in diameter, so, after tempering and putting them in the Roy´s device, took them to the grinder until they where just on the money, put them in the cylinder without the piston and put a strong light to see if there where any gaps, did not find any so, good to go (sorry for my english) ant the gap kept in .002-.003 in. after the "touch up" with the emery paper. and to Naiveambition, Lee Hogdson once told me that in fact the centrifugal force was the reason to abandon this engine, because the pilots when steering to the other side, had a great difficult to evade the enemy planes. Lee and Roy have been of tremendous help for me, I did the Ageless 9 cylinder radial before this one, after beeing in my first time at a NAMES show in Toledo, and step by in Lee´s booth, and after i showed him some pics of a Stirling engine (my firs Stirling) that I made, he told me "She (my wife was sith me) thinks you can´t do this, but I know you can, I will help you, just e-mail me when you need it", I am sure he regret sayin that, I wrote many many mails, and he was always very kind and tolerant, I decided to take some pictures and tape some video, here is the link in case you want to see it ,
Thanks to all again