Re: ATM Thin glass blank & some questions

[Richard Schwartz <richas@idt.net>]

If you slump the glass to form the curve, you will have to test it flat
on its back in a flotation cell.   The Ritchey sling will distort a
mirror that is not symmetric.

If you do not slump the glass to form the curve, you will be throwing
away a lot of the precious little thickness you now have.   I would not
be optimistic about success there.

I think your immediate need is to find the right refratories to make a
slumping form and to find a kiln that can do the job.   Most ceramic
kilns are controlled by "kiln sitters".  They are totally incapable of
doing what you need: a programmed cooldown from 575 C down to 375 C over
60 hours.   Double this time if you use an insulating material like
firebrick for your slumping form.

. . . Richard

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Date: Wed, 28 Jul 1999 15:43:55 -0700
From: Robert Der <rder@broadvision.com>
Subject: ATM Thin glass blank & some questions
. . .
And has anyone built their test stand, which uses a sling to
rest the mirror on? Any other recommendations for properly
supporting a thin mirror for testing purposes?

Thanks!
Robert
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