Re: [ATM] polish time for 13 inch

[hermit <hermit@outofoptions.org>]

Mel Bartels wrote:
>
>
>
> o.s. laps are easy to stumble onto.  I did so many years ago when pitch
> gradually sunk and worked its way over the edge of a 100% sized polishing
> tool.  I saw that I had a most exquisite edge and parabolic correction in
> the outer zones.  
I saw lap chipping myself.  It may have been more than a little over 
hang.    I just don't remember, but that probably influenced my thinking 
early on.  You remember that time before you learned the pitch lap was 
really your friend and not your enemy?   Also, you polish out quicker 
than most.  Us folks that are slower tend to keep the lap a tad smaller 
so that we can leave it covered and pressing between sessions.   Plus, 
there was a tale of woe a while back from some one that didn't take down 
that ridge left after a pressing and really turned his edge quite 
severely.   Funny how I remember the things that reinforced my methods 
huh? ;)


That said, the last mirrors I did broke some of my rules.  I over 
softened the pitch considerably.  I used it with much more weight than 
normal.  My machine struggled to make it through my 12 inch mirror, but 
a 6 inch mirror let me really load it up.  BABY BUTT SMOOTH.  By far my 
best surfaces.  There was probably no way that the lap wasn't over 
sized  by the end because of the weight and softness of the pitch.

Ken Lowther
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