In an earlier post, I mentioned I needed to make a simple hot air engine, called a Stirling Engine, for a Make Magazine article. I called up the head of the hot air engine forum on Google to see if he had any advice. Since by coincidence he lived fairly close by me, we made arrangement to meet at his house. Lots of engine projects going on there. He's got a mill and lathe so he can do precise machining. One of his current projects is to build a couple of steam engines to power a boat. Cool project.
Well, I spent all weekend on the project and finally got it to work late last night. I have no doubt that I made this a lot harder on myself than I needed to because I once I finished it, it really was pretty simple. Anyway my Stirling engine works and that's the important thing. Full and exhaustive details will be available in the Vol 7 (I think) of Make Magazine.
A couple people commented on a previous post that Stirling engines are sort of a black hole of engineering time and money. Every few years, it gets "rediscovered" and companies try to find a practical use for it. So far, there hasn't been much application, but as energy prices increase the calculus and economics of what makes financial sense and what doesn't seems to change. Maybe there will some use for these in the near future.
Also, here's a link to a review of my fab new book in the New York Post. An excerpt:
"Adventures from the Technology Underground" is an interesting read for everyone. Geeks like me will find it familiar, while non-geeks will get an interesting look into a different sort of world."