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Sonified ELF signals from California, Hawaii and Virgin Island locations with 16x frequency shift

Much of my ELF measurement was done at my home using a 150' pine tree as antenna. During the recording, there was a power failure at 30s...

Monday, July 14, 2008

Proposed new site for Open Stirling Engine project

I have created a google site for the project. It seems to have the features I need. It is at http://sites.google.com/site/openstirlingengine/Home check it out and give me feedback. Thanks.

Tom

4 cylinder Alpha Stirling engine almost complete


After working all weekend to build another half of the engine. It is almost complete. Unfortunately the first 2 cylinders have lost pressure, so I will have to track that down before I begin pressure testing. The 2 new ones seem to hold air well Got to go to my real job now.

Friday, July 4, 2008

Alpha Stirling engine protoype half done


I got 2 cylinders with push rods and cam assembled in a case. I changed the cam to a smaller one, cut from 1- 3/4" dia rod, so it is as smooth as glass. Pistons can now spin the shaft, now I need to add a flywheel to see if I can get it running. I have to be careful because it is still using polyethylene bags, so I have to limit the temperature.

Here is a picture of the partially completed prototype, but with the old cam.

Since I am using low pressure air as the working gas, the stresses on the push rods is not too bad. But I will need to add the cam follower guides so prevent the rods from bending when the press down on a inclined section of the cam with higher pressures.

I found a 7" flywheel pulley on my old vacuum pump. It had a 5/8" hole for the shaft, but I had a 1/2" bearing that had a 5/8" OD to adapt it. There is still not enough inertia to make on rev, so rather then getting a bigger flywheel, I've decided to complete the other 2 cylinders to balance the forces. Since they were always in the plan, might as well build them and test the entire unit. I will complicate matters having to apply heat and cold to 2 sets of cylinders. The other option would be to buy a larger flywheel from Grainger for $50. I guess I want to see it running before pouring more money into the project. I'll post a new picture soon of the assembled 2 cylinder version.