Re: ATM Re: Glass Balls

[Anthony Stillman <atmer@flash.net>]

>...a Machine for making spheres...
>http://www.jaderockshop.com/sphere3.gif.
>...Are both cups powered?  And are they counter rotating?


Yes, and yes.  This is the same principle used to generate glass, though
here the substrate is allowed to turn freely between the cups and not held
on a turn table under a spinning cup.

I've made a few small spheres and lens by hand using plumbing fitings as
the grinding cup and Silicon-Carbide then fine diamond for grit.  It was
hard on my carpal tunnel, but I'm happy with my 1/2" crystal quartz sphere
with its birefringent cross and optically active color rings.


Anthony