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8 Ways to Extend the Life of Your Vibratory Barrel

Follow these tips to get your money's worth out of a vibratory tumbler barrel.

Loto tumbler and UV10 tumbler barrels
Barrels for a Thumler's Ultra-Vibe 10 Industrial tumbler and a Lot-O-Tumbler. Ultra-Vibe barrels are made of heavy polyethylene. They wear slowly and can last for several years - if you learn how to treat them with respect and avoid some types of use. Lot-O-Tumbler barrels are made from high-density rubber and remind you of an automobile tire. With proper care they will last for many years.

Vibratory Tumbler Barrels Usually Last a Long Time

Most vibratory tumbler barrels will last a long time - usually a few years or longer - if they are used according to instructions and treated with care.

However, the barrels are not indestructible, and you may need to occasionally replace a barrel - especially if if you use the tumbler a lot, if you tumble certain types of material, or you follow practices that result in rapid wear on the barrel.

We want to accomplish three things with this article:


  explain a few things about how tumbler barrels wear


give you eight common-sense tips that can significantly extend the useful life of your vibratory tumbler barrel


warn you about the three easy-to-avoid weaknesses of Lot-O-Tumbler barrels.

Thumler's UV Tumbler Barrels

Wear Occurs During Every Tumbling Step

Barrels of the Thumler's UV tumblers lose a tiny amount of thickness with each batch of rocks. After you run the tumbler with some rocks, dump them straight from the barrel into a small container of water, swish them around and wait a few moments... you will see tiny black particles float to the top of the water. They will be smaller than a grain of fine pepper. These are tiny pieces of the barrel. We see tiny barrel particles in the white mud of our polishing, and in the soap suds of our burnishing step - so some loss of barrel thickness occurs even then.

Worn out UV-10 barrel
Here's how you can tell when your UV-10 barrel is getting close to "end of life". The bottom of the barrel starts getting so thin that you can almost see through it. Replace your barrel at this point to avoid cleaning up a mess!

What A Worn Barrel Looks Like

We have a UV-10 barrel that we used a few times a month for five years without it wearing through. During that time almost every rock that we tumbled spent its medium, fine, polishing, and burnishing steps in that barrel. It is the barrel in the accompanying photo with a translucent ring in the bottom.

We treated that barrel well. Most of the rough rocks that we processed in it were tumbled through the coarse grit step in a rotary tumbler (which removed sharp edges) or were tumbled stones from one of our suppliers that did not meet our standards for customer sales.

If we would have used this barrel for one or two more batches of rock, it would have started to leak rock mud through the bottom of the barrel.

The first sign that your barrel is failing is rock mud on the foam pad beneath the barrel. Watch for it! Better yet, each time you wash your barrel, hold it up to a window or a light and see if it is becoming translucent. That is the sign that you better get a new barrel or you might be cleaning up a big mess.

8 Ways to Extend the Life of Your Thumler's Barrel

You have control over the life of your barrel if you learn and practice these tips

We have been using vibratory tumblers for a long time, and we have learned a lot from customers, tumbler manufacturers, friends, and visitors to our website. Below we summarize everything that we know about extending the life of your vibratory tumbler barrel. We hope that these tips save you some frustration and money.

1)  Avoid Using Coarse Grit in Vibratory

We often hear about people using coarse grit (such as 60/90) in a vibratory tumbler. We disagree with that practice for two reasons. First, coarse grit will aggressively abrade your barrel. Second, coarse grit is usually too large to stick to the rocks during vibratory tumbling. It will sink to the bottom of the barrel, and the circulating rocks will grind it against the bottom of your barrel, wearing it thin prematurely.

angular aventurine
Angular pieces of aventurine about 1" to 2" in size. Tumbling angular rocks like these in a vibratory tumbler can gouge the bowl, causing rapid, premature wear. It is best to tumble rocks like these in a rotary tumbler for a few days before placing them in the vibratory bowl. Click image to enlarge.

2)  Avoid Tumbling Angular Rocks in Vibratory

We were tempted to name this tip "How to Kill a Vibratory Barrel".

The greatest wear on an Ultra-Vibe barrel occurs when angular rocks - especially large ones - are tumbled. If a person is tumbling broken agate or jasper or petrified wood or any other material in angular 3- or 4-inch pieces, the sharp edges of those big pieces will severely gouge your barrel! Those large sharp rocks can also rip holes in the foam pad that covers the bottom of the lid.

A few people have asked... "are the vibratory barrels guaranteed?" The answer to that is   "No! They are not guaranteed!"   The length of your barrel's life depends upon how you treat it. If you tumble big angular rocks, we DO guarantee that your barrel life will be very short.

We run all of our angular rocks for a couple days to a week (depending upon their size and hardness) in coarse grit in a rotary tumbler before placing those rocks in a vibratory tumbler. We do this because we prefer rounded tumbled stones. We also do it to reduce the wear on our vibratory barrels.

3)  Small Rocks and Rounded Rocks Cause Little Wear

A person tumbling small rocks or stream-rounded rocks in a UV tumbler might be able to use the same barrel for many years without wearing a hole in it. This is because small rocks don't exert much pressure on the walls of the barrel, and rounded rocks don't gouge material from the barrel walls as they are tumbling.

Most wear occurs on the vibratory barrel's bottom, where the rocks drag through excess grit. That's why you don't want sharp pieces of coarse grit down there abrading the bottom of the barrel.

UV-10 barrel to operating level
A UV-10 tumbler barrel filled to operating level with rough rocks and cylindrical ceramic media of various sizes. In Thumler's UV tumblers, if the barrel is only 1/2 to 3/4 full, the stones can be violently shaken by the tumbler. This can cause bruising of the stones, and the stones can hammer in the barrel, causing small particles of the barrel to be spalled off. Excessive noise is also produced.

By filling the barrel to nearly the top of the center pillar, the stones are less violently shaken, and the abundant media of various sizes fills the spaces between the rocks. The media cushions the stones during the tumbling. Click image to enlarge.

4)  Handle Dry Barrels with Dry Hands

Accidents account for a lot of the replacement Ultra-Vibe barrels that we sell. If you drop an Ultra-Vibe barrel that is loaded with rocks, there is a really good chance that it will break or crack. That's a really expensive mistake.

So, before handling a barrel, dry your hands and handle dry barrels. Don't take a chance that the barrel will slip out of your hands.

5)  Don't Tumble a Barrel Less than 3/4 Full

If you fill an Ultra-Vibe barrel only 1/2 full, here's what will happen. Your rocks will not tumble gently and smoothly - they will be given a very vigorous shaking. That vigorous shaking will make the rocks - especially large ones - hammer your valuable barrel. Every hammer blow can cause damage to your barrel. Some will spall off tiny black particles of barrel. Your $100 barrel is getting thinner. And, the noise will be louder than normal operation.

We run our Ultra-Vibe barrels quite full. Will fill them ALMOST up to the top of the pedestal in the center of the barrel. That produces a nice, smooth, quiet circulation of rocks in the barrel... and our money stays in our wallet.

Thumler's UV-18 tumbler
Shown above is a Thumler's Ultra-Vibe 18 vibratory tumbler. One important place to keep clean on all UV tumblers is the foam pad beneath the barrel. Pieces of rock, media, or other hard particles on the pad can wear a hole through the bottom of a barrel. Wipe the pad before each use and look for particles that might be embedded within the pad. Also, avoid placing the barrel on the floor or on a workbench where it can pick up particles that will transfer to the pad.

6)  Keep Your Base Pad Clean!

Here is another easily preventable situation that can result in a barrel wearing through much more quickly than expected. That is when small pieces of rock or ceramic media become embedded in the foam pad beneath the barrel.

When a loaded tumbler barrel is shaken on top of a sharp piece of rock in the pad, that can quickly wear a thin spot in the barrel, which can eventually develop into a hole or a crack.

It is very important to keep the pad clean and free of debris.

7)  Clean the Bottom of Your Barrel

Do not place your barrel on a dirty floor or on a dirty workbench, where small pieces of rock or debris will adhere to the bottom of the barrel. When you pick up the barrel and place it on the tumbler, those pieces of rock or dirt will transfer to the foam pad under the barrel. Soon they will be poking through the bottom of your barrel.

Best practice is to keep the workplace clean and wipe any debris from a dirty pad or dirty barrel before placing the barrel on the tumbler.

8)  Tumble Rocks in a UV Industrial Model - Not a Standard Model

Thumler's Tumblers makes four vibratory tumblers for rock tumbling use. They are the UV-10 Mini Bowl,   UV-10,   UV-18,   and UV-45. These four machines have working capacities of 4, 10, 18 and 45 pounds, respectively. The UV stands for "Ultra-Vibe".

The UV-10, UV-18, and UV-45 are available in an "industrial" model and a "standard" model. The "industrial" model is made for tumbling rocks. It has a heavy polyethylene barrel, heavy-duty springs, and a powerful motor. It is specially built for rock tumbling. The barrel that comes with the industrial model has a blue stripe around it.

The "standard" model is intended for light-duty cleaning and polishing of brass ammunition casings. It should not be used as a rock tumbler. Why? The barrel is very thin and the motor is light duty. The barrel that comes with the standard model has a yellow stripe around it.

Make sure you purchase the "industrial" model if you plan to tumble rocks because the standard barrels will have a very short life if used for rock tumbling. We only sell the industrial models on this website.

Learn how to tell the difference between the "industrial" and "standard" models.

Lot-O-Tumbler Barrels

Single Lot-O Tumbler
Photo of the Lot-O-Tumbler single vibratory tumbler with a hard rubber barrel.

debris in the well
Looking into a Lot-O-Tumbler barrel. In the bottom you can see a few pellets and other debris stuck in the well. There is no need to pry this material out of the well. That is one of the most common causes of barrel damage. Just rinse the barrel thoroughly and it will not cause a problem.

Lot-O-Tumbler Barrels

The Lot-O-Tumbler Single and the Lot-O-Tumbler Twin both use the same four-pound capacity barrels. They are made from thick rubber - much like the rubber that is used to make tires.

We have a Lot-O-Tumbler that has been used frequently since 2010, and the barrel shows no signs of wear. These barrels are extremely durable, and we have never heard of one wearing thin.

We sell very few replacement barrels for the Lot-O-Tumbler. If Lot-O-Tumbler barrels have any unusual vulnerability, it is the small cylindrical well in the bottom of the barrel. Small pieces of rock and ceramic media tend to get stuck in that well, and some people feel an urgent need to grab a big screwdriver and pry that stuff out.

Please resist that urge!

Prying in that well can cause the barrel to leak where the cylindrical well meets the curvature of the barrel.

If you allow a few pellets or tiny tumbled stones to remain in the well, they will not hurt a thing. Just rinse the barrel thoroughly and get on with your tumbling. It's not going to cause a problem.

The second vulnerability that Lot-O-Tumbler barrels face is the same as any other rubber product. If they are stored in cold or hot areas, or exposed to prolonged direct sunlight, they may become damaged. Temperature extremes and sunlight will cause the rubber to harden and crack.

The third vulnerability of Lot-o-Tumbler barrels is in exposing them to grease, oil, or other solvents that might attack the rubber. All three of these vulnerabilities are easy to avoid.

I believe that my Lot-O-Tumbler barrels will be enjoyed by someone long after my funeral. :-)

Happy Tumbling! Authors

Hobart King Hobart M. King has decades of rock tumbling experience and writes most of the articles on He has a PhD in geology and is a GIA graduate gemologist. He also writes the articles about rocks, minerals and gems on