Yesterday, I noticed a guy lapping a granite with a cast iron webbed surface plate. Obviously I thought that was interesting so I stopped to chat.
He had these levels (I think this is the brand), he laid out a x across the plate and a series of orthogonal lines. He took readings every 4 inches with two electronic levels. I'm not sure if that was a sanity check or what.
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Then some software on his laptop created a profile of the surface plate. From there he used his lap and diamond dust to work the imperfections out.I wanted to nail down a few more things but work got in the way. Imagine that, work getting in the way at work ;)
Anyway, that was interesting. Btw, he was a former AMF 82-70 pin setter mechanic. Small world.
Wes