[ATM] Mirror Scratches- and no tile tool available

[Adam Krause <krausea34@yahoo.com>]

Hello everyone,

I'm new to this list and have made a telescope before,
but this is my first time doing the mirror.  I
received a mirror from my friend that was already
ground, but still needed to be figured.  After years
of sitting in a box it has some scratches.  Being
untrained in grinding mirrors, I didn't really notice
them at first, but they show up under the Foucault
tester- especially when the knife edge blocks the
light on the mirror- it seems to leave only the
scratches to look at.  This web address shows three
pictures of the mirror with different brightnesses:

http://bellsouthpwp2.net/a/d/adamlisakrause/Mirror%20Scratch%20Pictures%2007-11-07/Mirror%20Scratches.htm

At any rate, the mirror came without a grinding or
polishing tool.  I have made the polishing lap and
have changed the figure some, but I don't know if
these scratches will come out with rouge.  Would they?
 I would rather avoid making a new tile tool to use on
a mostly completed mirror.  This brings me to some
questions...

Can I go back to some grinding grit and use it with
the polishing lap, or will the grit get into the pitch
and contaminate the lap?

If I do have to make a tile tool, would I have to go
back to a very course grit to grind the tiles down to
full contact with the tool, or could I get away with a
finer grit with not fully contacted tiles?  In the
case I had to grind the tiles down, what grit would I
have to go back to, and approximately how long would
it take to get full contact?

Thanks for your help.

-Adam Krause


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