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Do I Have A Dirty Polished Mirror?

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Posted by Scott Pelger on August 4, 2006 19:30:27 UTC

hi all,

i have been working on an 8" mirror off and on for some time. lately i have been wanting to get it done so i have been on again.

two weeks ago i tested it with a laser and the sun and see lots of scattering on the surface. since then i have polished for about an hour, 5 nights a week for two weeks. after week one i tested and saw no appreciable difference. the last week was spent with TOT (till then, 90% polishing was done with MOT). i tested again last night, and again, no appreciable difference. frustrated, i decided to take a look with a 10x lupe and the laser. what i saw suprised me. i can't tell if i see any pits for sure but what i do see is what appears to be striations, like tree rings. now, i only spot checked the surface and they are not in a circular pattern, they could have the "grain" of my last stroke but i can't be certain. i suspect it is my cleaning method becasue the light bands scatter the laser light while the dark do not. i suspect that the dark bands are bands of polished glass while the scattering bands are covered with dirt/CeO? i am cleaning the surface with soapy tap water and drying with a paper towel.

there are about 20 hours of polishing completed becasue of this. aside from a tiny hole/hill in the center it looks great under the focult tester.

is it possible that i have polished out completely but am not cleaning the surface properly? what is the best way to clean before testing?

thanks.

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