The piston is an important part of the Stirling engine. It helps regulate the chamber pressure while simultaneously pulling the flywheel, causing the flywheel to rotate.
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The piston needs to slide up and down quickly inside a tube, which makes fit essential. Since this was my first engine, I decided to purchase a graphite piston inside a glass tube online from Airpot.
I took one of the brass bolts that I was using to attach the block to the plates and filed it down on one side. I drilled through the flat part of the bolt so I could insert a wire hook to attach the piston to the flywheel later on.
I attached one of the nuts 3/16” from the hole I had cut into the bolt, then silver-soldered it on with a blow-torch.
Finally, I drilled out the center of the graphite slightly so the shaft of the bolt could fit through the graphite.
The piston assembly was finished!