stone coasters

[demented]

Here is a pic of a set of stone coasters that I have just finished cutting. Let me know what you think.

[davidmillerlowe]

Very Cool! What sort of bit did you use?

[demented]

I actually had to use alluminum bits 1/8 for the star 1/4 for the cut out running very slow. I used an old 20 deg. bit for doing the B.

[Greolt]

I have seen where people have carved stone before but not taken much notice.

What sort of stone can you carve with ordinary carbide bits?

Do you throw the bits away after use?

Do you run water as a coolant?

When you say "very slow" do you mean rpm or ipm?

Sorry for all the questions and thanks for posting.

Greg

[demented]

I'm not sure what type of stone it is, looks like granite but not for sure. I managed to use the bits more than once. Just cant use them on anything else. When I say slow I mean ipm I used 10ipm with a plunge of 10ipm and a cut depth of .0312 per pass took 30 mins. each just to cut them out.

[Rcnewcomb]

>What sort of stone can you carve with ordinary carbide bits?
Marble, limestone, sandstone, soapstone. Basically any "soft stone", i.e. 3 or less on the hardness scale. When I tried cutting granite with solid carbide the bit glows a bright red/white before it disintegrates.

>Do you throw the bits away after use?
Usually when a bit is too dull for wood I put it in the bit box for stone work. Coated bits work very well. Watch your cut quality and replace as needed.

> Do you run water as a coolant?
Only if you want a cement-like slurry all over your shop. I usually keep a shop vac nozzle near the cutter.

>When you say "very slow" do you mean rpm or ipm?
13,000 RPM @ 60 ipm. Keep your pass depth at about 50% of the bit diameter.

[Greolt]

Thanks for the info gentlemen.

Greg