GENERAL ROTARY TUMBLER INSTRUCTIONS
The tumbler will be running 24 hours a day for several weeks at a time, and needs to be in a convenient and safe location that will not interfere with family activities. It generates a slight humming sound. The motor becomes hot to the touch. This is normal.
1. Make it accessible. You will need to open it from time to time.
2. Place it near a power outlet. It must be located in an open area that is away from any flammable materials. DO NOT USE THE TUMBLERS OUTDOORS.
3. Do not put the tumbler on a table or other smooth surfaces. The vibration of the unit may cause the tumbler to crawl. A safe location is a concrete floor, such as in the garage or basement.
4. Do not put it in a confined space as it needs air movement for cooling the motor.
5. Do not let it freeze.
6. It is possible for the barrel to break open and spill. Make sure the location is safe for that possibility.
Check the tumbler on a regular basis to make sure the unit is running properly, is not over heating, and that the barrel is not has leaking.
Proper amount of material is needed to load the tumbler. Use a variety of sizes of the stones. Your barrel will need to be loaded about ¾ full of rock. A larger size rock may be tumbled but you must have all sizes of rock in the tumbler. About 1/3 of the load needs to be small size (1/4 to 1/2 inch in diameter). In small tumblers, a 1 inch stone is considered a large stone. The final output of the tumbler will be 25 to 35 percent less in volume than what it started with.
If you do not have small size stone a filler material can be substituted. This filler material can be broken TEMPERED GLASS. This glass can be found in the side and rear windows of a car. NOT THE WINDSHIELD. This glass can also be found at a auto glass replacement shop.
The amount of silicon carbide abrasive needed will depend on the size of tumbler you are working with. Weigh the stones (and glass if used) that will fill the barrel to about ¾ full. Then figure the amount of abrasive that is needed.
Rotary Barrel Tumblers use about 1½ to 2 ounces abrasive to 1 pound of material. OR about 1 to 1½ tablespoons of grit per pound.
Economical ungraded grits may be used. They usually are 60-90 coarse, 120-220 medium, and 400-f fine abrasives.
The tumbler grinding steps sometimes produces a “GAS” which at the right conditions will pop the lid off. To eliminate the gas you can add a “Tums” or a teaspoon of baking soda with the grit. (Do not add to the polish)
There are many types of polish that can be used. Generally talk with the rock dealers that sell tumbling supplies and tumble for their recommendations on what polish is the best for the materials being tumbled.
LETS GO TUMBLING
Step 1. To load a tumbler barrel, add the correct graded rough rock to about ¾ full, add the grit, and add water so it covers the rock by about ½ inch and seal the barrel.
Step 2. Place the barrel on the rollers and turn on the tumbler. Make sure that the barrel is turning and running quietly – with no squeaks or groans. Check the tumbler periodically to assure that it is operating and not leaking.
Step 3. The tumbler needs to run for 7 to 10 days (in some cases more time is needed for hard rock), 24 hours a day. The load may be checked to see how much rounding is taking place. This depends on the material being tumbled. Soft materials need less run time than does hard materials like agate, jaspers, and petrified wood. If the barrel is opened the seals of the barrel need to be cleaned before reassembly.
Step 4. Pour off the water and grit (slurry) into a disposable container (milk carton). A plastic colander or plastic window screen can be used to retain the stones. Wash and rinse the stones and barrel in a bucket of water. Do not pour the slurry or wash water in your home plumbing system as it will plug traps.
- When changing grits and polish, rinse well.
Dispose of the slurry it can not be reused.
Step 5. Place the stones back in the barrel with water to ½ inch above the rock and add some “IVORY” BAR SOAP. A chunk of soap maybe ½ X ½ inch in a small tumbler (1 to 3 pound) up to ¼ bar of soap in a 12 pound tumbler. The amount is not critical. Place the barrel back on the tumbler for 4 to 6 hours. Then drain and rinse off the stones again. This process will clean both rocks and the barrel, removing leftover grit, now you can go on to the next step.
Step 6. Place the stones back in the barrel with water to ½ inch above the rock and add the second grit. (120 – 220 grit). Seal the barrel and make sure the tumbler is operating correctly. This second grit will also run for 7 to 10 days (or more).
Repeat Steps 4 and 5.
Step 7. Place the stones back in the barrel with water to ½ inch above the rock and add the third grit. (400-fine grit). Seal the barrel and make sure the tumbler is operating correctly. This third grit will run for 7 to 10 days (or more), just like the previous two grits.
Repeat Steps 4 and 5. RUN THE WASH FOR 12 HOURS THIS WILL REMOVE THE LEFTOVER GRIT BEFORE THE POLISH STEP. Be sure to thoroughly rinse. It is critical to have no grit remaining in the barrel or on the stones.
Step 8. Place the stones back in the barrel with water to ½ inch above the rock and add the polish. The amount of polish powder is the same as grit. Seal the barrel and make sure the tumbler is operating correctly. The polish will run for 7 days. A thickening agent may be added to the water if soft stones are being polished. This thickening agent is sugar or corn syrup. The amount added will be twice as much sugar as polish.
Repeat Steps 4 and 5
At this time your stones should be polished.
Sometimes a Burnishing Run will improve the polish. This is a extra step with the use of powdered soap such as “IVORY” or “WHITE KING” in the same amount as the polish step 8. but run it for 4 days. Then wash and rinse them. DO NOT USE LIQUID DETERGENTS OR DISHWSHER POWDERS THAT HAVE BLEACH IN THEM.
GENERAL VIBRATORY TUMBLER INSTRUCTIONS
In a vibratory tumbler material loss is much less than a rotary tumbler. About 10 to 15 percent loss and the stones will be angular but polished. For the most part the procedures are the same as a rotary tumbler except for time, water, and the amount of grit used will be slightly less. About 1 ounce of grit per pound of material or 1 tablespoon per pound. The amount of water is much less. Use only enough water to achieve a good tumbling action. Too much water and the tumbling action will stop and the grit will settle out. Daily checks on the tumbler is a must since the slurry will thicken faster, more water is needed to be added. Run time is also much less. This depends on the hardness of the material being tumbled. Generally 2 to 3 days per grit will produce polished stones. On the daily check of the tumbler for the amount of water it gives you time to pull out 2 or 3 stones and wash them to check on how much material has been removed and if they are smooth enough to continue on in the next grit. Longer run times than 3 days will start to give a more rounded surface on the stones. The wash cycles in Steps 4 and 5 above are very important. The amount of water needed for a wash is the amount that produces bubbles with the soap.
In both methods of tumbling keeping a good record of what is done will help with correcting any problem that arise. Many variations of the general instructions are done. Discussions with other rock hounds or lapidary shops are helpful to correct problems in the art of tumbling stones. More advanced methods are available on the internet or book stores.
J.J. & L. ROCKS & MINERALS
P.O. Box 68
Hickman, NE 68372