To: atm{at}shore.net
From: ray{at}stabilite.com (Ray Desmarais)
Reply-To: ray{at}stabilite.com (Ray Desmarais)



Hi All,

Just wanted to make a few comments. I have found that the most important
things are. Good support under mirror.
I have had good success with packaging peanuts in a large plastic bag
fashioned into a circle.
It's a little larger than the mirror. The mirror needs to be pushed back
and forth until it settles. Next you need a lightweight tool to grind and
polish. The last thing you need is to flex the mirror while working it. The
less weight the better. I have used furring strips with masonite back. I
put the rough curve in the mold and filled it with expanding foam. Next I
put a masonite front on it and sealed it with clear coat. The grinding
tiles are pitched to the surface. For polishing I poured small pitch blocks
and put them on the surface of the tool.
Testing is a problem; the mirror folds in a conventional stand. I made a
tilting table and I do not go all the way horizontal. Which means that I
usually am testing 10 feet off the ground. I would use a meniscus blank to
get the maximum thickness.

I have successfully made a 36" flat .9" thick, and a 72"
mirror .9 " thick. That's right it's less than an inch thick. I'll try
to answer any questions the list has, Unless I perish in flames. There is a
link with pics of my shop and the scope at

www.oseti.org

Then select

all sky

Enjoy

RAY
Ray Desmarais
479-890-4918
ray{at}stabilite.com

Education is not something that can be completed. It's a way of life.

--- BBBS/NT v4.00 MP