Re: ATM 13" SCT update

[Buck Childers <buckchil@sound.net>]

<snip>
> The corrector plate was cut from a piece 1/2" thick white crytal glass.
> First the glass was checked with cross polarizers for strain.
> It just had a little shadow on one side so I cut around that side.
> The 13.75" dia. glass plate was biscuit cut with a homemade trepanning
> cutter on my mill-drill at about 30 rpm. This took about 40 min.

Hi Bob,
Can you tell me (us) more about your trepanning cutter.  

I'm wanting to cut some 1/2" glass into 6" and 7" disk.  I've started to
make a biscuit cutter with a plywood disk by attaching a mild steel band
to the paremeter.  I haven't tried it yet.  My drill press is sturdy but I
don't think it'll go below about 240rpm without a new set of pulleys.  How
slow do I need to get?  I planned on using a slurry of 120 carbo as the
cutting agent.

Thanks,
-Buck