OK, so now you have enough rocks to last you for a while, at least two - three days worth.
How are we doing on that equipment? Not enough yet probably eh! I would imagine that the tumbler was the first piece you went after. You can tumble to your hearts desire at least until you get a saw or a grinder saw combination. Rock tumbling is a process
The most common type of a rock tumbler used is a rotary drum tumbler. Don’t get me wrong, there are a lot of vibratory tumblers also used. Rough grinds in a vibratory tumbler are tricky. The rough edges on the rocks can chew up your barrel. That is the reason most folks use the rotaries for the rough grinds and the vibes for the smoothing and the polish step. If you want to use the vibe, knowing the draw back, it is faster.

You want all your rocks of the same approximate hardness in the load. Fill your barrel 2/3 to 3/4 full of rocks. Depending on the hardness or the rocks, most tumbling can be accomplished by just using two different grit sizes then on to two polish stages. Different rocks especially harder ones may need 4 different grit runs. The harder they are, it may take longer to get all the scratches and pits out.
I am accustomed to using 4 tablespoons of grit in my small tumblers per load. The first run is 60/90 silicon carbide grit. The second run is 120/220 silicon carbide grit. If after the first run (1-10 days) and the rough edges have all disappeared as well as most of the scratches, you can move on to the 2nd run. If not give them another 2-3 days of tumbling. Make sure the rocks and tumbler are cleaned thoroughly between each run. If you leave any contaminants in the tumbler or on the rocks between different grit sizes, your next step will be wasted time because you will be going to a finer grain of silicon carbide. I always run my rocks for a couple hours in just water and Ivory soap flakes between changing grit sizes. Dish soap or laundry detergent should not be used. They create way too many suds. Ivory soap and water tends to clean everything up very nicely. Discard all broken or pitted rocks from each batch. That is if the edges are not rounded. If the roundness all appears to be the same, you can leave them in. I hope I am not confusing you with all these instructions, but you do want some nice shiny, smooth and highly polished rocks, right. Good! That’s what I want for you also!
Don’t throw the broken or pitted rocks away. Keep them for the next batch. If you leave them in, they will only diminish the quality of the other stones being tumbled.
Expect the process from beginning rough to polished results, to take at least a month.
Plastic pellets can be used during the 2nd run and during the polish stage to cushion the rocks from each other and to carry the slurry from rock to rock. They do not need to be used in the first stage. In the first stage, we want them to bang together and help remove the sharp edges. DO NOT use the same pellets during the polishing stages. They are contaminated! Use new pellets. Do not use the contaminated polish pellets in the grit runs. Throw them away also after being used.
Don’t be afraid to open the container at any time to check the progress. By doing so you can check to see that the slurry is forming properly, or that batch is not too dry, and opening the container will also relieve gas that the rocks are producing. Too much gas trapped inside the container will result in less tumbling action. You can expect to lose about 15% of each stone size during the two course tumbling processes.
For tumbling softer stones, they should be checked more often, and using a tablespoon less of grit per batch.
Do not get in a hurry to change steps. Leaving contamination between steps and changing to the next grit size too quick, are the two top reasons for a bad polish result.
DO NOT overload your tumbler barrel. If your tumbler is rated as a three pound tumbler, it will handle three pounds of rocks almost indefinitely. Overloading is the prime reason for motor burn out.
If when done with the entire process or during any of the steps, you notice some rock sizes are disappearing excessively or are not polishing, you are more than likely mixing much softer rocks in with harder rocks. It is important to tumble all rocks of the same hardness together. If you do find this happening, and the rocks are just the run of the mill rocks, don’t worry about it. But if they are expensive rocks, you may want to correct it on the spot.
Use a prepolish after the grit steps. A good pre polish is 800 grit Aluminum Oxide. Rapid Polish is a good medium to use as a final polish, or there are more expensive polishes to use, Linde A for one. Again, clean everything between batches. You Want No Contamination carried from step to step.
It would be advantageous to you to have one tumbler barrel for grinding, and one for polish. Do not mix them up. I use a permanent marker and mark mine with a G for grit, and a P for polish. Keep them clean and dry when not in use. Wash the dust off and out of them before using. Storing them so they become damp will cause mildew to form. Mildew & Polish is not compatible! K
Sometimes you will find a “trouble rock” in the batch when done. That’s one in which where the pits are just too deep to be removed. If it is a run of the mill rock, no problem. If you definitely want to keep it for a special reason, you can run it over the grinder and grind the pits out and put it in the next batch. There are some that you can grind away the pits and some where nothing helps them.
Once a great shine is put on a rock, the shine will virtually last forever, even with handling. It can still be scratched but you won’t be attempting that with a nice looking specimen on purpose.
I kind of like that old saying, “if at first you don’t succeed, try again”! That is a good way to go about this hobby! You will get it! I am confident you will!



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