robbiejohn
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|  | how to cut obsidian?
« Thread Started on Jul 20, 2011, 2:16am » | |
Hi friends, I went to town today and found about 1.5 pounds of obsidian at Vinnie's Thrift Shop (75 cents). It's in three pieces, roughly 3" x 5" each, up to 1" thick. Some edges are thin and extremely sharp.
I've never tried to polish this glass as I haven't had any rough material. Now with this, and maybe getting more, it may be time to try.
It would have to be made into much smaller pieces, and I'm stumped as to how to cut it. Would my trusty little 7" tile cutter likely work. Using a saw seems counter-intuitive. I would expect the material to shatter. Can anyone set me straight on how to get it into smaller bits? Also, would it work to make up a load by adding pieces of ordinary glass?
Thanks for your help. Cheers! Robbiejohn.
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ColtChainmailJewelryDesigns
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| | Re: how to cut obsidian?
« Reply #1 on Jul 20, 2011, 3:18am » | |
Cutting it with a saw is a GOOD thing!!!! It's not likly to shatter unless it gets snagged or something. But I really should zip it before I say something that i dont even know about the truth, lol!
You can smash it with a hammer, but with so little amount you have, not a good idea. Smashing Obsidian make lots of tiny shards. But that isn't the way I do it anymore. And I find you can get lot less tiny shards (if any) if you hold the rock, and tap it on a sledg hammer on the ground! Seems like it brakes off larger bits. =)
~Colt
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johnjsgems
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| | Re: how to cut obsidian?
« Reply #2 on Jul 20, 2011, 8:05am » | |
They make expensive 7" glass cutting blades to fit tile saws but for what you want to do your tile blade should work OK. Breaking with hammer would not be my first choice.
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Steve
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| | Re: how to cut obsidian?
« Reply #3 on Jul 20, 2011, 11:05am » | |
Whatever you do - wear eye protection.
You're better off tumbling obsidian with obsidian (of the same type). Using glass as a filler may work, but there are too many variables to know. Not all obsidian and not all glass are created the same.
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jspencer
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| | Re: how to cut obsidian?
« Reply #4 on Jul 20, 2011, 11:33pm » | |
As suggested in another post I tried a small diamond blade on my Dremel a few nights ago and found that it cuts it like butter and no chipping on edges. You get less waste than your tile saw would create. I know I`ll use mine for it again when needed. The blades are pretty inexpensive too for the Dremel.
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susand24224
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| | Re: how to cut obsidian?
« Reply #5 on Jul 21, 2011, 12:36am » | |
Overall I agree with Steve--many variables between glass and obsidian. That being said, I just tumbled some glass and obsidian and the variables worked out in my favor--both tumbled and polished nicely. I remember reading that glass can be as low as Mohs 5 in hardness and obsidian is 6-6.5 so it seems that if anything goes wrong it will be with the glass. This is just a *slightly* educated guess, though
Susan
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tkrueger3
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| | Re: how to cut obsidian?
« Reply #6 on Jul 21, 2011, 10:19pm » | |
In fact, a lot of folks cut up obsidian to "dress" the saw blade. It's a very versatile substance, for sure. And it can be made into gorgeous jewelry, too!
Tom
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