Instructions for Using Rock Tumblers
- 1). Unscrew the cover and fill a tumbler barrel no more than three-quarters full of rocks to be polished. Weigh the rocks to make sure you do not exceed the weight limits of the tumbler system.
- 2). Add grit and fresh water. The first tumbling phase uses the coarsest grit available. A good rule of thumb is to add 3 teaspoons of 60/90 coarse silicone carbide grit to 1 1/2 pounds of rocks; 4 teaspoons to 4 pounds of rocks; 10 teaspoons to 6 pounds of rocks and 20 teaspoons to 12 pounds of rocks. Grits are available at science stores or hobby shops.
- 3). Clean off the rubber seal with a rag. Any grit left on a seal before the cover is screwed back on will cause the water to leak out. Screw the cover on and place the barrel onto the tumbling wheels of the machine.
- 4). Plug the tumbler in, and if it has a switch, turn it on. It will begin to tumble, and should be left to tumble for the next seven days, 24 hours per day.
- 5). Remove the barrel from the tumbling wheels. Open the cover and pour the contents into a colander which has been placed into a bucket. Allow the rocks to drain completely. Rinse them using a fresh, warm water source.
- 6). Place the rocks back into the tumbler and add grit. This tumbling phase uses a 120/220 fine grit. Add the correct amount of grit per package and weight instructions. Wipe the seal off and screw the cover back on. Allow the barrel to tumble for an additional seven days straight.
- 7). Repeat these steps using progressively finer grit. Most grits are tumbled with rocks for seven days, 24 hours each day. However, different grits by different manufacturers may have alternate directions. Eventually, as each grinding phase is completed, a polishing phase begins. Plastic pellets can be inserted to shield and cushion the rocks during the polishing phase.
- 8). Add a mild soap solution to the rocks during the burnishing phase. Allow them to tumble for one or two days. Rinse. The rocks will be shiny and polished.
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