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Bob Ver Hoven,          Brick, NJ            7/18/2005

1/2 Size Miser (Jerry Howell Plans)


After building two PM Research kits, I wanted an engine project that required me to build most, if not all, of the parts from bar stock (i.e. no castings). I came across Jerry Howell at one of the Cabin Fever shows and was hooked on his Miser design at first sight. The Miser is a Low Temperature Stirling Cycle (Hot Air) Engine design. I bought the plans and opted to build the half size version to make it more in palatable for my Sherline equipment. The bore is approximately .3" and the flywheel is about 2.75" in diameter.

I learned a great deal while building this engine: Lapped my first cylinder, Discovered the art of holding very small pieces while machining them, Built my first spoked flywheel from scratch, Learned how not to polish/buff parts, and learned to have the much needed patience to search for the ridiculously small pieces for this engine when I dropped them on the shop floor....

I didn't have any major issues with during the construction. I took my time and pretty much followed Jerry's plans and associated tips. My biggest problem came during assembly/reassembly. Before painting I decided to dry fit everything and test run the engine first. It pretty much ran the first time using a cold pack as the "fuel". I then disassembled the engine and attempted to polish/buff and paint. Apparently I was a bit too aggressive in the buffing process. After reassembly, the engine refused to run. Turned out to be air leaks. A bit of sealant here and there fixed that. I am currently running the engine over a "night light" 4W light bulb to break it in. I hope to fine tune it after a couple weeks or so.

In my opinion, Jerry's plans and customer service were fantastic. Jerry had the patience and took the time to answer my numerous questions on the machining aspects/setup for some of the parts for this engine. A special thanks is also in order for Bob Verhaeghe and Mike Walters who privided me with much needed advice during the construction of this engine.



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