Post by 4cornersrocks on Sept 7, 2009 13:02:34 GMT -5
Disclaimer! For informative purposes only! Stone dust is bad! Electricity is dangerous! 
I just thought this was interesting and could help out some of us interested in cutting soft stones on a budget. This works great for turquoise, jet, lapis, marble, serpentine, etc...
I have seen some cutting setups used by the local Native American jewelers in my area. These lap units are very cheap and do a great job with soft stones such as turquoise.
Here is how you do it...
Get an old belt driven shop grinder (with the motor on a very long belt, far away so you dont get any water even near it, use a gfci too!!!) on 1 side use a 220 carbide wheel and on the other side a homemade plywood wheel with leather on the flat surface. The 220 wheel is used with a sponge held to the wheel with just enough water to keep the stone cool and damp. An even safer way is to regularly dip the stone in a jar of water. You don't want it wet, this is just a shop grinder. Use a gfci! To cut the flat back of the stone, use the flat side of your 220 wheel. After it is flat on the back dop that side and shape the dome side on the 220 wheel's normal grinding surface, once again either by using the sponge or by constantly dipping the stone into a cup of lukewarm water.
After the stone is shaped you can sand with 600. You dip the stone in water to keep it cool and so no dust is formed. Some people use their knee and some cloth sandpaper to sand.
Another way is to get some rubber or sponge and tack it and your sandpaper on a paint stirrer, you then rub the stone back and forth like on a flat lap.
Sometimes the 600 stage is skipped depending on the stone!
The last stage is dry polishing on a leather wheel, smooth side out. Back to the grinder! Use some kind of metal polish from the hardware store or zam if you can get it. Keep the stone cool by keeping your pressure down most of the time, using the slow part of the wheel and by being patient. Don't let the stone get hot or it might discolor or crack.
All materials except an old arbor style grinder can be found at a hardware store. I bought my old style grinder for 30 bucks at the flea market with a nice american made motor and new wooden base.
I hope this is helpful and makes sense! I have seen beautiful stones cut this way and you can cut a lot of stones at once.
I just thought this was interesting and could help out some of us interested in cutting soft stones on a budget. This works great for turquoise, jet, lapis, marble, serpentine, etc...
I have seen some cutting setups used by the local Native American jewelers in my area. These lap units are very cheap and do a great job with soft stones such as turquoise.
Here is how you do it...
Get an old belt driven shop grinder (with the motor on a very long belt, far away so you dont get any water even near it, use a gfci too!!!) on 1 side use a 220 carbide wheel and on the other side a homemade plywood wheel with leather on the flat surface. The 220 wheel is used with a sponge held to the wheel with just enough water to keep the stone cool and damp. An even safer way is to regularly dip the stone in a jar of water. You don't want it wet, this is just a shop grinder. Use a gfci! To cut the flat back of the stone, use the flat side of your 220 wheel. After it is flat on the back dop that side and shape the dome side on the 220 wheel's normal grinding surface, once again either by using the sponge or by constantly dipping the stone into a cup of lukewarm water.
After the stone is shaped you can sand with 600. You dip the stone in water to keep it cool and so no dust is formed. Some people use their knee and some cloth sandpaper to sand.
Another way is to get some rubber or sponge and tack it and your sandpaper on a paint stirrer, you then rub the stone back and forth like on a flat lap.
Sometimes the 600 stage is skipped depending on the stone!
The last stage is dry polishing on a leather wheel, smooth side out. Back to the grinder! Use some kind of metal polish from the hardware store or zam if you can get it. Keep the stone cool by keeping your pressure down most of the time, using the slow part of the wheel and by being patient. Don't let the stone get hot or it might discolor or crack.
All materials except an old arbor style grinder can be found at a hardware store. I bought my old style grinder for 30 bucks at the flea market with a nice american made motor and new wooden base.
I hope this is helpful and makes sense! I have seen beautiful stones cut this way and you can cut a lot of stones at once.
