Thread: Any amateur mirror makers still alive in Oz/Nz?
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  #64  
Old 02-02-2012, 01:13 PM
clive milne
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clive milne is offline 		 
Join Date: May 2011
Location: Freo WA
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A rough sagitta calculation indicates that the central thickness of a 25" f4.2 made from 19mm float will be around 10mm, and a bit over 12mm for the 22's...

Courageous!
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