[ATM] a dozen tiny clamshells

[Glenn Becker <burningc@sdf.lonestar.org>]

Hello ATMers,

I've been working away at my childhood 6", which is going to go into a 
telescope for a college friend and his sons. Tonight I was getting towards 
the end of a round with 25 micron when I noticed (guess I should have 
noticed before ...) that a few arcs of my bevel had gotten worryingly 
slim. So I pulled out a grinding stone and had at it ...

... only to notice, after rinsing and drying the blank, that there were a 
number of new big sparkles all around the very outside edge of the 
ground surface. When I took a closer, magnified look, I found that I had 
nicked about a dozen tiny clamshells into the very edge.

So I'm guessing trying to bevel at that stage was not a very smart thing 
to have done. Well. @_@

Now that the damage is done I am wondering what, if anything, to do about 
it. I'd like to avoid going backwards in grits, back to rough grinding or 
something like that, for flaws as small as these. I recall from the Sam 
Brown book that he says a badly turned down edge can be "masked" out of a 
mirror. Would a similar approach be called for here? None of the 
clamshells is more than a couple of mm big. Will they affect the 
performance of the finished mirror?

Thanks in advance,

Glenn Becker

+-----------------------------------------------------+
Glenn Becker - burningc@sdf.lonestar.org
SDF Public Access UNIX System - http://sdf.lonestar.org
+-----------------------------------------------------+
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