Re: [ATM] Richard's blanks...

["Bob May" <bobmay@nethere.com>]

The little dimples weren't easily visible with the unground blank
on the ones that I've done.  They really showed up when I started
grinding tho!  It may be that Richard is taking more care to
insure that there is no dirt on the mold when he does blanks now.
Remember that those blanks need special handling when applying
the lap and make sure that you have a notice to the effect that
you don't want to stress the glass with applied hot stuff as
there isn't the strength to handle the heat stressing that a
regular blank will take.
When I made the lap, I did it under water so that the whole
mirror would be at teh same basic temp.  If you don't do this,
the probaaili9ty of the mirror blank breaking is almost assured -
I was the first to successfully finish a blank as all of
Richard's attempts failed during the preparation for polishing.
Bob May
bobmay at nethere.com
http: slash /nav.to slash bobmay
http: slash /bobmay dot astronomy.net
Replace the obvious words with the proper character.

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