Thumler's Tumbler Rotary Rock Tumbler

Started using this January 2025. I've gone through a couple tumblers. The motor is whisper quiet! The only noise you hear is the media in the barrels. No mechanical issues to report! The motor housing does get a bit hot but not unreasonably, and it has never overheated on me and stopped. Buy this one, save yourself the aggravation!

Pro's: this Amazon seller was 10$ less than others; simple; good hard rubber tumbler containers with flats inside for effective tumbling action - and a simple reliable seal design; Made in USA.Con's: lack of pride in quality control - ink pad print was blurred & incomplete (seriously, wipe the wet ink off and print it again); motor has a low-quality loosely crimped together housing (paint is chipped around crimps); motor fan does not circulate much air and just running constant with little load in the tumbler containers at room temperature (70degF), the motor case gets to 158degF (should have a "Caution HOT Surface" label at that point); motor cord wiring was separated well beyond the strain relief; no rubber feet results in loud vibration and damage to table surface over running time (recommend 4 stick-on rubber cone feet 20mm dia x 22.5mm height, they work very nicely).I recommend a little Tri-Flow teflon lube for the plastic sleeve bearings. Once the bearings are lubed and cone rubber feet installed, the unit is comparatively much quieter.

Love the tubs, but the construction of this machine for $200 is ridiculous. The motor runs hot all the time, I cannot trust this machine to be left unattended for fear of fire hazard. The tubs are really good so they are now inventory for another tumbler from somebody else.

High quality piecenof equipment backed by one of the best names in tumblers.

My wife is a rockhound and science teacher. She has always bought inexpensive rock tumblers from walmart or other junk retail stores. These rock tumblers have always have been for kids who will play their tumblers one or twice and nevermore. They are cheap, loud, and too small.I ordered her Thumler's Tumbler model A-R2 about eight years ago. She uses it often and it still works years later. She is currently running it for her new collections from our trip to Michigan's UP and the Middle East. It is low maintenance. It is quiet. It has a good capacity with its two side-by-side rubber drums.Things to know when buying this:1) You have to oil the rollers with machine oil. You have to oil the motor with electric motor oil. I use 3 in 1 brand oil for both. (As in I have a standard black can for the rollers and 3 in 1 blue can electric motor oil for the two oil ports on the little motor.) You just need a drop of oil under each roller. You just need a drop or two of electric motor oil for each port on the motor. Do not use machine oil in the electric motor.2) You have to really clean the drums after use including when changing the grits. My wife has missed this a couple of times. Leaving grit on the outside surfaces of the rubber drums chew up the drums and the rollers. Leaving grit on the lid or the groove the lid snaps into will cause the drums to leak and chew up the seal for the lid. Clean the drums, inside and out, very thoroughly. If the grit can polish granite , it certainly can devour the rubber of the tumblr. Get all of the "rock grit mud" out of the drums and off all surface after use or when changing grits. When kept clean, however, I have had no problems with leaking or the rubber bearing surfaces or drums eating itself. Do not let kids pour the spent grit mud down your sink drains.3) Unlike the junk tumblers in mall stores or retail chains, this tumbler is quiet. Ours runs dutifully on the floor near the dining room table. When we eat meals or play board games it goes unnoticed. (We keep it there so I remember to oil it and I can keep on eye if my wife let the seals leak.)4) I suggest not getting this for a kid for birthdays or Christmas as a first rock tumbler. Get a junk one first, burn it up, and run it to fail. However, if the hobby sticks then this tumbler is a great one as a "first real rock tumbler." Thumler has several other sizes too. Likewise for a school teacher or part-time hobbyist like my wife, this two-drum A-R2 is a perfect entry-to-middle level tumbler. If she keeps up with it, I might upgrade her to the larger capacity Thumler Tumbler ( A-R6, A-R12, or B model--Check their website for more information).5) If you only have enough rocks to fill one drum. You will need to find something to fill and run the other drum. We usually wait until another rockhounding trip. There is media that be bought to fill the idle drum to ensure the weight balances and keeps the drums from wandering around. Like I said, we merely just go on another trip--We live in New England and there are rocks everywhere. We just find an excuse to fill the other drum.In closing: This is a good reliable rock tumbler that isn't noisy. I'm pleased with its performance. It is good for a kid with a demonstrated interest in hobby. The tumbler is ideals for part-time hobbies or teachers. Remember to oil it properly and keep the wearing surfaces clean and free of grit and this tumbler will last years.

I was a bit taken aback by the light, simple construction. My guess is you could build one for about $15. But the watertight containers were something else again. They are indeed watertight and made of a very tough sturdy rubber that would probably outlast the rest of the machine ten times over. Probably the whole machine is worthwhile to buy just to get the containers.