Re: ATM Starting out & Plaster Tools

[Bruce Swayze <swayze@europa.com>]

At 01:11 PM 9/13/97 EST5EDT, you wrote:
>I've received my 6 inch kit from Newport Glass, and
>I'm getting ready to start grinding.  I'd like to try and
>make two mirrors from the kit, one from the pryex
>blank and one from the plate glass tool.  I know I'll
>need to buy more abrasives.  Does anybody have
>a source for dental plaster or other good tool
>material in the Toronto area?  
>
>I also seem to recall reading about using a pipe
>section to start hogging out the curve initially.
>Does anybody have any experience with this, or
>should I stay away from it since this will be my first
>mirror?
>-- 
>Tom Hayko

Tom,

I would avoid the idea.  Not because it's your first mirror, but because
you are doing a 6-inch.  Small mirrors like this don't need such an
aggressive technique since you aren't removing much glass to reach your
desired depth of curve, and you'll be there fairly quickly.  You will also
save yourself the time and hassle of making a full size tool out of tiles
or whatever after hogging out the curve with the pipe section method.  Not
to mention the work grinding to make such a tool reach good contact and a
spherical curve that matches your mirror.  All in all, it's just not worth
it.  

Keep it in mind, however, when you're ready to attack that 16-inch or
20-inch.  Just my opinion, and I hope it's helpful.  

Clear skies,


"*-.,_,.-*"`"*-.,_,.-*"`"*-.,_,.-*"`"*-.,_,.-*"`"*-.,_,.-*"`"*-.,_,.-*"`"*-
Bruce Swayze
swayze@europa.com
http://www.europa.com/~swayze    Swayze Optical Home Page 
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