Re: Another ATM scope sees the light of day....err night :-)

[spooner@page.az.net (Michael Spooner)]

Malcolm Macdonald wrote:
> 
> >My 10" f5.8 had it's official first light tonight.   My only regret is the
> large number
> >of scratches in the glass.  In the second-to-last figuring session I
> >contaminated my full sized lap while I was trying to scuff it up with a
> >wire brush. I think it picked up some rust.  (Another lesson learned.)
> >-Buck
> >
> This happened to me too, recently. A whole lot of scratches appeared and the
> only thing I could think of to blame was a wire brush that I had just used
> to scuffed the lap. It was an unused brush that I had bought special for the
> job, to avoid contamination. I hadn't finished polishing so went back to a
> fine grind, and have now almost finished figuring with no further scratches.
>  Buck, your post has confirmed my suspicion that wire brushes (even new
> ones) shed, something.
>  The question is now, how to treat the brush to remove rust or any other
> contaminant. Soak it in oil? Perhaps some of the chemists on the list could
> suggest a treatment that would sterilise the brush without creating a new
> problem.  Do they make stainless steel brushes???
>   Although scratches are not the end of the world, I think most of us know
> how disheartening it is when they appear at the end of the process, (and it
> always seems to happen then) after all that painstaking work.
>   Malcolm.
> ===================================================
> Malcolm Macdonald.
> Rotorua / New Zealand.
> 
> The trouble with experience is, you always get it after you need it.

WHen you're close to being polished out, scratch the lap with a razor
blade. Just 2 or 3 fine scratches across the facets and a set 90 degrees
to the first. mike