Re: ATM 21" f/6 - Status report and a question

["Stathis Kafalis" <s.kafalis@planet-interkom.de>]

You must be a very strong man, to push and pull a 21" lap. Something between
14 and 17 inch and working tool on top would be much healthier for your back
and arms. Be sure to put the mirror on a flat surface with

Years ago I made a 17,5" with a 10" tool working tool on top with
excentrical strokes with 1-3" overlapping in order to catch the edge as
well. Center end edge polished out at the same time and it became spherical
like hell automaticaly. However it took quite a long time, since 10" was
quite small a tool compared to the mirror size and I worked with a slow
polishing powder.

Texereau's lap method should work, but it looks quite complicated. I think
the are easier ways.

----- Original Message -----
From: "Ken Bertapelle" <kenb@cqg.com>
To: <atm@shore.net>
Sent: Thursday, October 26, 2000 12:40 AM
Subject: ATM 21" f/6 - Status report and a question


>
> All,
>
> For those interested, below is a recap of what has happened on my mirror
> project.  Here is a question for the more experienced members out
> there:
>
> Question:
> =========
> I'm planning on using gugloz #64 pitch on a full size pitch lap, MOT to do
> the polishing.  I think I'll use the method described by Texereau to make
> the lap - pouring the pitch into molds and cutting tile squares.  What
size
> pitch square do you all think is good for a 21" polishing lap?  The book
> shows 3/4" squares, but will larger ones work?
>