Re: [ATM] mirror grinding

["David Harbour" <scarab2@cox.net>]

Peter,

I've seen this. I believe it was in one of those two volumes Wilman Bell
published, the new ones, covering "recent" (last 30 years) of amateur
telescope making innovations. I believe I would rather not use Terra Cotta
tiles for the cutting face; rather, harder tiles, such as the Winburn Hex,
or the other new, square, porcelain  tiles. Winburn folded, went out of
business. Besides, it's easier to make stacks of tiles than sideways
sandwiches of them, I would think. How many layers would a guy need, anyway?
I can't imagine more than about four or five layers of .2" hexes (or
squares). I'm sure it worked for him; but was it necessary, I wonder? I
wonder how much tile he had leftover? I'll bet, quite a bit, after grinding.
But remember, Terra Cotta is a lot softer than porcelain.

Ritchey ground elegant channels into his all glass tools. The ultimate
tools. Glass, with channels ground in. Ritchey was a perfectionist, as well
as a genius (with a flawed personality, like yours truly). Thanks for
reminding me of this-

Davey

dave


----- Original Message ----- 
From: "Peter John Smith" <pjifl@bigpond.com>
To: "The Amateur Telescope Makers List" <atm@atmlist.net>
Sent: Tuesday, June 28, 2005 8:29 AM
Subject: Re: [ATM] mirror grinding


> Another way to make tiles last a long long time is to stack and glue them
on
> edge so they are effectively very very deep.
>
> This is an idea I originally saw in the McIntosh edited book which owed
much to
> the Maksutov Papers way back.  Dont remember the originator of the idea.
>
> Peter Smith
>
>
> _______________________________________________
> ATM mailing list http://www.atmlist.net/
>


_______________________________________________
ATM mailing list http://www.atmlist.net/