3.6LB Professional Rock Tumbler Kit with 10 Belts, 3 Speed Settings & Digital 9-Day Timer, Rough Gemstones, 4 Polishing Grits, STEM Science Kit for Adults Kids

The media could not be loaded. Seems excellent so far, and I'm ordering another one as well. I have more expensive tumblers but I couldn't pass this one up for the price - if it was garbage then I could modify or repair it, or just return it. Except that so far it's actually decent quality! The drum is fantastically large with its diameter, better than other 3lb drums I've used. It's a belt-driven unit, meaning that the drum rotation is driven by a flywheel connected by a belt to the motor. It comes with multiple spare belts, but those could be easily 3D printed in TPU or just use large rubber O-rings. Being belt-driven, the speed could be fine-tuned by replacing the flywheel with a different diameter wheel. But I don't think this will even need it. One of the biggest problems with inexpensive tumblers is that they don't tend to have a slow rotation, just fast and faster (e.g., 80RPM and higher, too fast for good tumbling). I measured the speed on this unit (full drum) using a tachometer and it is in the perfect range:Speed 1: 25 RPMSpeed 2: 37 RPMSpeed 3: 56 RPMIf I don't update this review, then it means that it's a definitive 5 star rock tumbler. I'll report back if there are any issues encountered.

Not really a good choice. I had a cheaper one from another.. popular... site that has an orange logo and got hit by bad tariffs recently.. that lasted longer. However, the motor on that one went out so I went looking for a new one. It's really just temporary to hold me until I get my vibratory tumbler in.The problem with this is that the "belts" for the motor are basically plastic. I've only tumbled ONE type of rock so far, and it was Chalcopyrite which is less than 1 day per stage, and it quit on the next set of rocks. It would actually *start* turning, and get maybe one rotation, and quit. I turned the speed up thinking maybe it just needed the momentum to keep turning, but it didn't work. So I thought *MAYBE* I had put too many in there, so I took half out (even though that other cheaper one held *MORE* than what I was putting into this one). It still didn't work.Well, it came with about 10 "belts" (again, they're not belts, because they're basically plastic) so I tried replacing that. It worked. SO FAR, it's still going, but it does seem to be an uneven speed. The current rocks are agate, which is about 5 days per stage. That means I may need to replace the belt again before the first stage is even done! Instead, I'm going to measure the belt in a moment, and look up Alliance Sterling rubber bands on Amazon in the same size. (That brand has a very high rubber content, and very low clay content, so they last longer than cheap rubber bands.) Then I'm going to try using the rubber bands in place of these so-called "belts" and see if that works better.But I really don't want to buy *ANOTHER* rotary rock tumbler while waiting on the vibratory tumbler (which the manufacturer said will take about three months before they have more). So I'll just figure out a way to make this piece of crap work until then.

Just received today and I am already tumbling a batch now!! Works great, runs quietly and seems to be made of good construction!!

Edit… seems I submitted my review too soon. The drum being gummy has become an issue so that this is now unusable. Didn’t make it through polishing even the first set of rocks. Looking at it closer, the drum has developed wear spots and won’t stay on the rollers anymore. So kinda junk at this point.On the 3rd cycle for the included rocks. So far so good. The drum has walked off the rollers once. The machine did turn itself off when that happened. I’m also starting to question how long the drum will last. Every time I pick it up it leaves some soft rubber that is hard to remove on my hands. The first belt is leaving tons of material behind as well, but the kit does include lots of those. Other than those two concerns it is working great so far.

Great Value! For the small money they are asking, this is a great little tumbler. It has been running for a week with an overloaded barrel (well over 3.5 lbs including stone, grit, media, and water) and is still going fine. The barrel is huge, but thin walled so is a but noisy, which is no issue for me. I plan to order another one

So far so good. I was leary of the belts after reading reviews but had a backup plan. The tumbler has been running 8 days straight on the same belt now. The belts it came with were green so they possibly changed the material? The speeds are not super variable. The barrel is more flimsy than the others I own but truly this is great product for the cost!

I ordered 8 of these and wound up returning all but one. the one I kept was only because I didn't have the box to return it. It started out good but after a few weeks they die. The spindle on the lower motor burn out and will no longer spin, or will snap drive belts one after the next from the heat generated.

Fantastic tumbler for rounding gemstones!