Re: Polishing preparation was: ATM pitch lap question

[Alvaro Cortizo <alvaro@netpandora.com>]

Hello Ken,

Monday, February 25, 2002, 9:04:44 PM, you wrote:

KH> I do not understand what you are doing...

Because  i suck explaining things on English... is not your fault, its
mine :(

KH> You say that you are pressing the mirror with the convex glass tool
KH> which is glued to a dental stone?

KH> I have never heard that described before.

Yes Ken, i will try to explain it:
On bottom: Pith Lap (convex)
On  Top  of  that  the mirror (concave), with , off course the "mirror
side" on the pitch lap
On  Top  off  all the above: the Glass tool (convex - used to grind the mirror)
with the convex side over the center of the flat "back" of the mirror,
so, im pressing (or flexing) more in the center of the mirror, than in
the  outside,  is  pretty  the  same  thing as if i press with only my
finger  on  the  center of the mirror (but i dont broke my finger that
way) :)

Anyway, using that method (hot pressing only on center of the mirror),
and  after  that  pressing  the  mirror  "flat"  i made a good contact
surface all over the mirror now, so the pith lap is "fixed"...
The  problem  was : i was using too much weight to hot press.. i didnt
know that i must not use a super-weight over the mirror :)

KH> You should have...

KH> A glass mirror (concave)
KH> A tool of some sort that the mirror was made with (convex)
KH> Another tool for polishing, made from the mirror's curve.
KH> This tool for polishing will be CONVEX and will be your pitch lap...
KH> Hope we are together so far.

[EDITED - REMOVED FROM HERE]
[.....]

KH> Sorry that this turned out to be such a long description but judging
KH> from the description of what you are doing, I think you and others
KH> might well be advised of the steps involved .

And thank you for that long description!!
You clarify some dark points to me, and i bet to some other ppl too :)

-- 
Best regards,
        Alvaro
Rosario, SF, Argentina