Re: [ATM] Glass Types

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

The type of glass isn't important at all.  The important thing is the finish
that glass can obtain with proper polishing.
I will note that lead glass is a bit more brittle than ordinary soda lime
plate glass so the grinding will go a bit faster but the glass will also be
more jubject to severe cracking from rough handling.
Also, due to the higher coefficient of expansion, the finished mirror will
also go further out of shape under changing temp conditions thus making a
scope that will be a little more difficult to cool down.
Bob May
bobmay@nethere.com
http://nav.to/bobmay
http://bobmay.astronomy.net

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