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Pyrex vs borosilicate glass.

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#1 dscarpa



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Posted 29 January 2013 - 10:59 AM

I was just reading the email Rob Teeter sent me reguarding the 11" F/5 Zambuto is making for me. He will be using his last 11" Pyrex blank. I didn't realize this when Rob called me and said Zambuto had a blank he could use for my mirror. The new blanks are made with Schott Supermax borosilicate glass. It would mean waiting 6 months more to get my scope with the new glass but I would gladly do it if it made for a better mirror. David

#2 Jason D

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Posted 29 January 2013 - 11:03 AM

They are the same


Borosilicate is the glass type
Pyrex is a trademark

#3 dscarpa



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Posted 29 January 2013 - 11:12 AM

Thanks for the info! That's a relief. David

#4 Achernar



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Posted 29 January 2013 - 11:48 AM

They are the same kind of glass, which contains boron, hence the term borosilicate. All glass is mostly made of silica or silicon dioxide, it's the presence of other elements in it that determines it's optical and mechanical properties. Supermax will work just as well as Pyrex will for a mirror.


#5 Mr. Marbles

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Posted 29 January 2013 - 01:42 PM

Have no worries, Carl would never let anything leave his shop that did not meet his optical standards. He wouldn't use any material that'd perform less than perfectly.

#6 John Kuhl

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Posted 29 January 2013 - 05:16 PM

Yes they are the same, but what is the thickness of each one? If it was me I would get the thinner one of the two, and is there a price difference? Just a couple of things to consider.

Best, John

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