The casting part is easy - just get the pyrex hot enough to flow. The hard part is annealing the glass. This takes a bit of time to go through the annealing temp range and the thinner the glass, the quicker it goes. If the glass is thick, you may want to consider doing a larger mirror and slumping the glass after having melted it into a larger diameter chunk. I know that places like Newport Glass (in the LA area) and United Lens (on the east coast I think) can do the job for you. Most pottery kilns aren't large enough to really be able to handle the needs of the mirrors that us astro types want to put in them but your local university may have a kiln that is big enough and that's just a matter of asking the right person the right way. Good luck and next time, don't drop the glass - it does cause a lot of heartbreak when it happens.

• Re: glass casting - Rick Crockett o - February 8, 2000 - 01:58 UTC