MJR Tumblers Commercial Duty 20lb Rock Tumbler. Capable of Running 18 Different Barrel Sizes & Combinations. Unmatched Quality, Durability & Versatility. MJR is a USA Disabled & Veteran Owned Company.

i bought this tumbler due to its high capacity and the excellent price. its a sturdy machine and at 25lb capacity the opening is big enough for larger items. as of yet no signs of issues. great value

This tumbler is better than most for durability and versatility. Make sure to purchase Lithium Grease you will need it to operate. The price is expensive but it’s a well built tumbler base. And it’s versatile in that this one tumbler can fit a variety of barrel sizes. I purchased the 10lb barrel and have been running 2 3lb barrels.To run smaller barrels I did have to make a modification to the nylon bumper, by adding a longer bolt with a nylon washer to extend the bumper out farther. The MJR barrels have a wide ridge that sits in the rollers. Smaller barrels don’t have such a wide ridge which means they could slip off the rubber roller track. Simple fix to make this adaptable to more barrel combinations.Primary issue noted is belt breakage. The manufacturer sells replacements for $8-15 (depending on tumbler base size) for only one belt. These are just simple O Rings. The size for the 10 lb. tumbler is 4 1/4” x 3/16 “. I found Nitrile O-Rings for $12. Don’t get durometer harder than 70 or they’re too brittle and snap.

This thing is too easy to use, works well, I usually find the rocks and my husband does the polishing, it works out for us😊

I downloaded a tumbling log online and everything is running smoothly.

Tumbling rocks. We are working on the first batch and it is in the 4th stage and we have been happy with all the results so far. We did have to look on line to figure out how to fill the drum so more info on the process would be nice. It is a good quality. We would buy this product again.

Works great

Just in setting the machine up was complicated as you can see from the photos the motor mounts that are used to adjust the belt tension are located directly underneath the rollers so that you can not access them with a normal screwdriver. The problem is the same on the underside where the motor itself is in the way of putting a normal socket or wrench on them. The result is that after less then 24 hours of running the belt has already posed off one freezing the motor up while not popping the circuit. When I checked the machine after 24 hours to degassing the drums I discovered that drums not moving and motor hot enough to burn you if touched. This thing could have burned my entire shop down!!! As you can see from the photo whatever happened to the machine while it was running took the rubber coating on the main drive shaft and shifter it all the way to the left so that it now rubs against the bearing. This machine for its price is a complete piece of garbage, a buyer would be well advised to stay as far away from this item as possible unless you want a premade machine ready for you to modify into a fully functional tumbler. The tumbler barrel are made out of PVC and would be easy to duplicate for the price of them as well. For the price of this unit the quality should be 1000% better. Because it comes packaged in two boxes returning this piece of garbage back is going to new a massive PITA that would not be necessary if the company focused a little more on design and quality control.

This is one of the best purchases I have made ever!