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Re: Everybody Should Have This Problem (24" Blank Too Thick)

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Posted by Phil Owen/">Phil Owen on March 30, 1999 00:46:09 UTC

Thanks for the tips. I have to learn how to do the "polarizer test" to determine if there is strain in the glass after i cut it. that is of course i figure a way to cut it.

I have aquired the following blanks:

A 36" x 1.5" thick fused silica blank with an 8.5" perforation. it has a curve that i havent checked yet.

A 27" x .75" thick fused silica blank with an unknown radius of curvature.

A 20" x 1" thick flat that is already coated.

And of course the 24" mentioned above.

I also have some 10" pieces of BK7 lying around somewhere...


: A 1 in 6 blank is the old standard for thickness to dia. You can cut it in half if you want to and not worry about stress. The problem is finding a machine to do it. You may make a cutter yourself but the cutting will of course take a bit of time. Good luck. If the 24" is the smallest, what is the bigger ones and are all of them pyrex or is there some optical glass in the bunch?

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