From: atm{at}misterg.fsnet.co.uk (Andy Gray)
To: "Atm" 
Reply-To: atm{at}misterg.fsnet.co.uk (Andy Gray)


Warning - this is a comment from a rank amateur!

I have felt tempted to post this comment before to those whose polishing
has "stalled", but haven't really got the depth of experience to
validate it - anyone who disagrees with this is probably in the right:

Make sure your rouge mixture isn't too thin - Other considerations apply
when trying to get the best surface after the pits have gone, but for the
moment, you are concerned with stock removal. I believe I genuinely
stagnated when polishing my only (first???) mirror after mixing a fresh
bottle of CeO2 - I was seeing the same surface every time. Thickened the
rouge up a bit (thin yogurt - ish) and there was a visible and sustained
improvement after every wet.

YMMV.

Andy

Andy Gray, Dyserth, N. Wales



On Sun, 20 Apr 2003 22:40:09 -0400,  "CSC"  wrote:

>
>Maybe I missed a previous post, but how long have you been polishing? I'd
>say a 12 " can use plenty of pressure and can be a workout.  10 hrs isn't
>too much for a good polish.
>
>Rough up the lap with a wire brush or make a new one.  Use net to raise the
>action on the lap.
>
>If you feel the scratches need to go, go back to 12 micron.  5 doesn't seem
>to remove much glass at all, and I've always had to go to 12 micron.  Saves
>time.
>
>Colin
>
>-----Original Message-----
>From: owner-atm{at}shore.net [mailto:owner-atm{at}shore.net]On Behalf Of Scott
>Berfield
>Sent: Thursday, April 17, 2003 12:23 PM
>To: atm{at}shore.net
>Subject: ATM Polishing
>
>
>
>I am getting a little frustrated and need some advice. I Seem to be
>making VERY slow if any progress on getting the 12" to fully polish out.
>I think I need to go back to fine grinding to reduce some of the
>remaining pits (which seem suspiciously deep) and to get rid of a couple
>of small scratches I managed to pick up despite my best efforts. I am
>considering going to 5 micron and maybe even trying for 3 before
>proceeding back to polishing.
>
>I also am considering going to pads to polish with to make up some of
>the time lost. I have never used pads and wanted to get some advice on a
>source and on the proper use.
>
>As I understand it the pads are applied to the surface of the tool and
>charged with polishing slurry then polishing proceeds the same way as if
>you were using a pitch lap - correct? Does one need to use a different
>stroke pattern or are there other concerns to be aware of?
>
>Thanks for all the help on this - who knew a piece of glass could be so
>humbling?
>
>------------------------------------------------------
>Make no little plans; they have no magic to stir men's blood.
>- Daniel Burnham
>
>
>
>
>

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