I now have part of Chris’s improvements to my Lehman Seismometer implemented.
I have the ball bearing installed on the pipe union, and carbide bit on the boom.
I extended the boom to 36 inches and got the5lb weight to 27 inches out.
I did not put the coil on the boom...I left the magnet on the boom and coil on the base plate.
I removed the oil dampener and added a new 1/8 copper plate, thicker than what I had , hopefully the magnets are adjusted correctly for the dampener.
The Lehman now has a period of 21sec what a difference the ball bearings make!!!!
I am going to build a second Lehman and I will put the coil on the boom on that one.

Thanks Chris and everyone that has helped

Bryan S Goss
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