From: "David M. Bourgeois" 
To: atm{at}shore.net
Reply-To: "David M. Bourgeois" 


One of these years I plan on grinding an 18", and I thought I would
try flexing, so I have a couple of questions.

If you follow this procedure and grind the back out to a sphere with #80,
what would be the best way of supporting the mirror once you return to
attack the front?

How carefully would the bevel have to be applied (by hand in my case)?

On Fri, Jan 17, 2003 at 08:32:23PM -0700, Bill Kelley wrote:
>
> Peter,
> My 2 cents. The back does not need to be fine ground. Hog out the front, hog
> out the back to the same curvature, dewedge, clean up, fine grind the front
> (checking for wedge on the coarser grits), polish and figure a sphere. A #80
> grit surface on the back will not give you trouble working to 1/1000th
> wedge. An irregular bevel on the front might throw you off if you are
> reading wedge from the back with the mirror face down.
> Bill Kelley
>
--
David Bourgeois  -->dbourgeo{at}thezone.net http://home.thezone.net/~dbourgeo/
#  "Research is what I am doing when I don't know what I am doing."
#  - Wernher von Braun

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