For my school science fair, I decided that I wanted to make something that would also help me improve my machining skills. I made a Low Temperature Differential Stirling Engine as designed by James R. Senft in his book “An Introduction to Low Temperature Differential Stirling Engines.” This engine is a closed cycle engine (meaning no air goes in or out) that runs off minor changes in heat, such as the heat of a cup of coffee or a bucket of ice.
Here is a photo of the raw materials I started with:
I then machined all of the parts (with the exception of the piston and cylinder, and the screws). I used the drill press, the lathe, a sabre saw, table saw, two homemade Hot Wire Nichrome Foam Cutters, a laser cutter, files, a grinder, scissors, bolt cutters, and a soldering iron in this project.
Here is a video of the finished engine running on top of a cup of hot water:
I will put up more detailed photos and explanations of the build process in future posts.
