Mat, part of me wants to do the whole "Dobson" experience, and actually use screened beach sand for rough-grinding... No shirt, grind it on a picnic bench with hair in a pony-tail, figure it with only a light-bulb..."eat well, sleep well, work like hell"... and being only 53 and in great shape, I'm sure I could do it... OTOH, having made a few mirrors (and NOT made of the same stuff as Dobson, lol), I'm all in favor of using any and all labor-saving "devices" available... ;-) John Dobson is one-of-a-kind. We won't know his ilk again for several generations. I've never had the bad experience of reaching the figuring stage only to find out that the blank has astigmatism from internal stress due to lack of proper annealing. And I don't want to EVER experience it. But I couldn't pass up an 8-1/2" piece of glass for less than thirty bucks! ATM's could benefit from an intervention. It's a sickness. ;-) On Wed, Feb 15, 2012 at 3:54 PM, Hutchings, Mat (H USA) < mat.hutchings@siemens.com> wrote:
I never have. I have wanted to, but never got around to it.
Mat