Out of necessity - The ground glass on my 12x20 broke during shipment.... it was packed plenty good, but it was just one of those things, oh well.
So I checked out the listing for 12x20 ground glass.... huh? Nada!
Alright, I checked out that ebay seller with the high marks....... available but how much? Ouch, it's $1/sq. in for float and $2/sq in for borosilicate..... so $240 or $480 for a 12x20 ground glass?----- HAHAHA! I don't think so.
enter D.I.Y.
First I read this page
http://www.dokasphotos.com/techniques/ground_glass/
Sounds easy enough right? Well it is easy, it just takes time and elbow grease.
I got my supplies here;
http://www.willbell.com/ATMSupplies/ATM_Supplies.htm
Get the white al oxide lapping powder in 3 and 5 micron size (I got 1lb each, way too much material but what the heck)..... I also got the cera-hex-tool for $9.
Then you just sit down in front of work surface and start grinding. - Well I had to build the grinding tool first but that was pretty easy. The hard part is grinding to the very edge, it might work better to grind first then cut to final size, but if you break it wrong you waste a lot of time.
It turned out great...really really nice, and bright, even using soda lime glass. I'm going to grind another as a spare since I had two blanks cut.
I'd like to experiment with borosilicate glass but it's really expensive, so maybe in the future.
Here's a couple photos, I'll post the finished product later.
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