Re: ATM Grinding area cleanliness

["Bob May" <bobmay@nethere.com>]

Cleanliness is a very interesting subject when talking about glassworking.
Twyman has a bit of info on the subject in his book that can be of interest
to many.  Basicly, he considered that grit sitting on a table to be innocent
unless somebody picks it up and deposits it on a glass surface.  Thus you
don't put your hands or other things on the table and carry them over the
surface you are grinding as this will allow the grit to be carried up and
over onto the surface.
He also noted that fine scratches tended to go up when the floors were well
swept as the fine grits on the floor would be tossed into the air and, by
Murphy's Law, the grit would land on the surface of the glass.  Same thing
with heating vent systems blowing air all over the place.
I consider that the rough grinding (down to 320 grit) is coarse grinding and
just keep working along with the old grit without any problems.  When the
320 grit is done, I then clean up and go onto the fine grits.  Instruction
is given as to the process of not passing things over the glass at this
point as this could carry grit up and over the mirror and thus allow the
grit to fall on the surface of the mirror and make a problem.
Anything more that you do than this I more consider just being supersafe.
I'm not going to be taking a shower and fresh clothes every 2 hours when
going down through the grits tho.
Bob May
http://nav.to/bobmay
bobmay@nethere.com
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