Re: ATM Grind a convex hemisphere?

["Bob May" <bobmay@nethere.com>]

Swap the glass and tool to make a convex surface.  If you want to
pregenerate the curve, the cup type wheel is what is used, sitting i at an
angle so that the proper curvature is obtained.  Note that in either convex
or concave pregeneration, the corner of the cutter is all that is really
used to generate the curve.
The professional optician is equally capable of grinding and polishing both
convex and concave surfaces without problems.
Bob May
http://nav.to/bobmay
bobmay@nethere.com
NEW! http://bobmay.astronomy.net