Greetings, the project was shelved for the summer so I could finish a Vertical Axis Wind Turbine I was working on. Thanks for keeping me focused, my one real concern is trying to run the compressor as a Sterling is the oil needed for the piston rings. There have been times when hot air engines that have exploded using oil in the crank case. I plan on adding a snifter valve to the crank case that feeds the back pressure back to the top side of the piston that will be very similar to a project posted on Youtube. I also will add a pressure release valve and hopefully with the combination of the two I will be able to avoid any dangerous situations. I am trying to keep machining to a minimum and the parts are off the shelve and available at Lowe’s. Thanks for the post and best regards.