|
Post by greig on Nov 29, 2016 14:32:04 GMT -5
Safety is so important. Some of the rocks and minerals have stuff in them that are horrible to breath or eat. Also, flying objects can be nasty. Every time I have been lazy, taken a shortcut or tried to play with tools, without the proper gear, could have potentially been a disaster. One time that I was really lucky was chiseling a huge quartz/garnet/calcite rock. I badly wanted the thing to split, so I could carry it. I forgot my safety glasses in my truck and was too lazy to go back for them. While wailing away at the thing with a 5 lb sledge, a piece went over my shoulder and sounded like a bee going by. I put on sunglasses and the next swing of the hammer sent a chip right into the glass. The luck of a fool. ;-)
|
|
richardh
spending too much on rocks
Member since June 2016
Posts: 391
|
Post by richardh on Nov 29, 2016 16:31:04 GMT -5
How do you do it safely? I bought an angle grinder from Harbor Freight for about $20 and a 4" diamond cup wheel. My first problem was that the thing spins so darn fast and I was really afraid of getting hit by any part of the wheel. I think the grinder I got runs at 11,000 rpm. Based on a photo that jamesp posted here I made a little guard out of sheet metal and a plastic bucket lid so only a small portion of the wheel was exposed. It worked fairly well until the wheel started getting uneven wear. Once it got a little off balance the whole rig started vibrating more and more violently. Eventually my guard shook to pieces and the grinder went completely out of control flapping around on the ground. The only way I could shut it off was to yank the plug. It scared the heck out of me. Unless I can find a safer way to deal with the grinder I'm using other methods for making tumbler feed. I have done it a couple of different ways, and free-handing (holding the grinder in one hand and the stone in the other) works OK, but it is REALLY fatiguing, and I would stop short of calling it safe. This weekend, I did some rough grinding with it and think I found a pretty decent sweet-spot. I took the grinder and "mounted" it in the jaws of my workmate at about a 30-degree angle. Then I finagled a rubbermaid bowl under it and filled it with water, just to where it was touching the blade. I wasn't using a cup wheel, I was using a 4" segmented, scintered diamond blade. That isn't NEARLY as aggressive as a cup wheel, so MUCH less fear about chewing off the ends of your fingers. That actually is about the easiest way I have found to do it. I think moving away from the cup wheel will make it a better experience for you. Thanks very much for the info. Do you have a variable speed grinder?
|
|
huskeric
spending too much on rocks
Member since May 2016
Posts: 353
|
Post by huskeric on Nov 29, 2016 18:08:26 GMT -5
I have done it a couple of different ways, and free-handing (holding the grinder in one hand and the stone in the other) works OK, but it is REALLY fatiguing, and I would stop short of calling it safe. This weekend, I did some rough grinding with it and think I found a pretty decent sweet-spot. I took the grinder and "mounted" it in the jaws of my workmate at about a 30-degree angle. Then I finagled a rubbermaid bowl under it and filled it with water, just to where it was touching the blade. I wasn't using a cup wheel, I was using a 4" segmented, scintered diamond blade. That isn't NEARLY as aggressive as a cup wheel, so MUCH less fear about chewing off the ends of your fingers. That actually is about the easiest way I have found to do it. I think moving away from the cup wheel will make it a better experience for you. Thanks very much for the info. Do you have a variable speed grinder? I don't. It runs at 11K RPM, so it's about the furthest thing from gentle you could ask for. It's a Porter-Cable PC60TAG.
|
|