Cutting marble and granite

[msantos]

Are there special bits to cut marble and granite. Marble and granite will be used for headstones.

Thanks

[shoeshine]

Marble = no problem, standard carbide v-bits work (though I am partial to the centurion vbits for stone, IMH a better geometry)

Granite = good luck... you would need diamond bits at a minimum and I doubt the bot would be up to the stresses involved. the guys I know who manufacture granite countertops have very specialized CNC equipment in the multi hundred thousand dollar range.

marble and granite are two very different beasties.

ask your supplier for a Mohs scale # for your stone (this is a relative measure of hardness) anything under 4 or so is do-able. marble, slate, soapstone, etc... (granite is around an 8)

Chris

[jerry_stanek]

I thought that they make a mask and sand blast granite.

[dhunt]

Useful and informative links:

http://en.wikipedia.org/wiki/Mohs_scale_of_mineral_hardness

http://www.amfed.org/t_mohs.htm

[cowboy1296]

I like your comments about marble. My shopbot is a prs standard. So I am assuming still no problems. I have cut corian which turned out to be a snap and liked the end result.

[Brady Watson]

Cutting stone on a Bot can get downright nasty. If you don't have adequate dust collection, you might as well oil your machine and roll it around on the beach. If you plan on cutting anything else, like wood, plastic etc, then forget it. It is not worth the mess & highly potential damage to the machine's bearings, rails and drive system - Let alone your poor spindle/router bearings.

Granite is worse than plunging your bit into concrete. Picture that if you will :eek:

-B

[dave_k]

...Granite is worse than plunging your bit into concrete. Picture that if you will :eek:
-B
...wow, talk about putting things in perspective. Note to self: do NOT attempt to cut granite on my bot!