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book drawing of grit grain sizes

Started by piekielrl, 02/03/2008 10:19PM
Posted 02/03/2008 10:19PM Opening Post
Hello, I have just about every telescope making book from Willmann Bell. Somewhere in one of those books was a drawing of the various grit sizes and the corresponding chunks of glass they remove - the coarse grits looked like boulders and the finest ones looked like sand. It might have been on a left page in the upper part of of the text. There might have been a caption something like "The guy went crazy trying to polish out a defect for 100 hours when he should have done it by fine-grinding..."
I can't find this drawing! Does this ring a bell with anyone? Do you know which book/page it might be on? Thanks! Bob Piekiel
Posted 02/04/2008 04:57AM #1
Bob,
I think you may be referring to a drawing by Russell Porter in ATM vol. 1(pg 352 of my copy). It has a diagram of the time to polish pits of different grain sizes, and in one conrner is a tombstone with the inscription "Here lies a T.N. who died of old age while trying to polish out No. 60 pits with rouge".
Gary Fick