MJR TumblersSingle Barrel Rock Tumbler - Rock Polisher Machine, Tumbling Equipment for Stone, Glass, and Metal Collection, Polishing Tool for Adults & Kids, 10 lb

Fantastic machine at a great value and built simply so it's easy to understand. Been running mine everyday for almost two years. I had a breakdown from a bearing seizing up and MJR's customer service was wonderful. They shipped out the replacement parts at a very reasonable cost and had me back up and running in no time. The repair was straight forward and it made me more familiar with my machine. After repairing it, I realized that this is a lifetime product and I couldn't be more satisfied with the quality of the device, or the customer support. It reminded me of the acronym - KISS (Keep It Simple, stupid!). I was hesitant to purchase because I learned my craft from a gentleman using Diamond Pacific, but I couldn't afford that brand's product. I am entirely happy that I found MJR and the results are identical to what I was aiming for out of DP.

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.

I've had my tumbler for years now and I love it, much better than the others I've used. Just a note, it takes less time to polish than the others I've had.

Despite the high cost of the unit it lacks an on/off sweitch and must be unplugged to shut it off (cripes!!!). Additionally it seems to have the same vulnerability of belt breakage, despite the fact that it has bearings (do NOT let this mislead you. NOT particularly a good value for the cost. thus I would not have bought it had I known..

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 a great unit that deserves 5 stars. There were two problems viewed. When the container is on the rollers it does not always turn the container. I had to etch or scratch groves on the container to increase traction with the rollers. It loaded it with 8oz of lead balls and 300gram or 10.58ounces of BP or 1.16lbs total. Adding additional weight was of no help. Temperature potentially played a part as it was cold outside between 19° and 35°.Item 2 - the protective plate on the outside grinds against the wheel and had to be removed. Bolting position is not adjustable and had no clearance. Bending it away or removal were the only options. Since, at the location where to two pieces were grinding, I took a ball peen hammer to create a divot in the metal cover to allow clearance. BOTH minor issues. The unit has run and operated perfectly with the minor adjustments. Would recommend to anyone.

I have a 3 lb rubber barrel tumbler that I absolutely love. Needed a larger tumbler and bought this on. Opening and closing the barrel is more difficult u need a tool to do so. You can’t use a screw driver u need a socket wrench. The thing I dislike the most, is rocks get wedged and stuck at the bottom under the inside channels. I would not recommend this one. Very expensive for what u get.

We have had this tumbler for less than a year and the bottom of the jar blew out. We tried to contact MJR without success. I would not recommend this product. We picked this one because of the rating.. never again.