Re: ATM pitch lap woes--help appreciated

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

If you're worried about the rapid heating from water, just let the glass sit
in there while heating and cooling and don't put too much heat into the
water.  That should be a lot less stressful on a mirror than it hitting
really hot pitch on the surface and helping to cool it down a good 100F or
more so that it doesn't flow much.
I've been working on some of Richard Schwartz's mirrors and have done that
technique as his designs are probably quite fragile with uneven temp
changes.  Leastways, he's having troubles with some of his pieces shattering
by the time that they come out of the oven.
Bob May
http://nav.to/bobmay
bobmay@nethere.com
NEW! http://bobmay.astronomy.net