Rotary tumblers (Lortone) polish rocks through a series of four steps which are outlined below:
Coarse grind 60/90 grit 1Tb/pound
Medium grind 150/220 grit 1Tb/pound
Fine grind 500 grit 1Tb/pound
Polish Titanium Oxide 1/2Tb/pound
Barrels should start out about 3/4 full and not be allowed to drop below 2/3 full. If too much rock grinds away and the barrel becomes less than 2/3 full just add some polished rocks or use plastic pellets to refill. If you do use plastic pellets, keep a separate bag of pellets for each grit so that you do not carry some embedded grit forward and contaminate the next step. To figure the amount of grit, just weigh the barrel empty then fill to 3/4 full with rocks and weigh again. Add enough water to make a slurry (like gravy) with the grit if possible. Too much water just allows the grit to ride on the bottom of the barrel. Each step should run about a week. Step one does all of the shaping so if you are not happy with the roundness after one week, repeat step one with fresh grit. It is common practice to follow the polish step with a one day tumble in water containing a powdered soap like Dreft.
The most common problem is to not get everything properly washed off between steps! Just 1 or 2 grains of grit carried forward can do a lot of damage when they are tumbling around for a week!
Enjoy your tumbler! Be sure to let us know if you're having problems. We'll be happy to try and help you figure out what the problem is. If you're having great success, we love to hear about that too! Bring in some stones for show and tell!
© 2015 Veberod Gem Gallery Minnetonka, MN 952-595-8338 . firstname.lastname@example.org