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BVC Glass Problems
Forum List | Follow Ups | Post Message | Back to Thread Topics | In Response To Posted by Ron White on April 1, 2003 17:22:06 UTC |
I ground a 16" mirror from BVC glass. I Bought a 16" plano and ground it to F4. this blank is made from 1/4" thick sheets fused together when I cut thru the first layer and into the second it had massive voids-- very ugly --( I don't mean bubbles these areas were like 1 to 2 square inches in area) the zone area between the sheets of fused glass polished different from the rest of the of the mirror surface so figuring was a bear. I got the mirror to an 1/8 wave except for the fused area but the voids made it to ugly to have coated. I did mount and star test the mirror and the views were awesome with the 6" center / fused / ugly / area blocked off. I had a problem with scratches because of chips of glass from the void edges flaking off. I solved this By stopping the grinding at 12micron grit and polishing from there.
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