Re: [ATM] Does exposed Pyrex lose polish over time?

[Andy Saulietis <iss@pvtnetworks.net>]

Tom Krajci asks,



>Microcracks in the polished surface?
>
>Does this mean the polish was incomplete?

Paul Jones (the mirror maker) says these microcracks
are sub-sub wavelenght in size & result from the grinding
process. After coating I didn't see any visual evidence
of inclomplete polishing (pits, sleeks, or scratches) in
direct sunlight.

I can't vouch for the accuracy of Paul's theory, but we do
know that 5 min of re-polishing fixed the coating corrosion
proble. Other mirrors I've used that he's made did not have
this problem. They were made from regular sheet Pyrex 2 1/8"
thick.


Andy Saulietis
ISS Enterprises
10 Milky Way
Mayhill NM 88339


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