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Probably meehanite cast iron rather than steel. Yep - looks like a long-radius grinder for CX surfaces. Did you put a spherometer on it yet?

If you don't have a spherometer, an old trick Joe Appels showed me was to clean off your grinder, then spray WD-40 on it and get the sun's image in focus and measure the distance to focus. Not as accurate as a well-made and calibrated spherometer but better than trying to stack up valve shims under a straightedge.

Mike

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I will clean it up and check its focal length..I had that idea earlier myself. I have everything to make a spherometer..just haven't gotten round to it..but I will.

Second...I finished my first tubes table..it is a cast iron 8.5" table and I put one of my students 8" mirrors on it and tried out the polisher...OH it's so sweet....Much easier then the Porter polisher.....

I'll post images tomorrow.

Thanks.

Rob

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www.goldmtobservingcenter.com
A great place for amateur astronomers, and ATM's to come and enjoy their hobby.

http://tech.groups.yahoo.com/group/HomemadeRefractorTelescopes/ My homemade refractor group.

www.vimeo.com/6014031

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