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6 Reasons Why Your Rock Tumbler Leaks and How to Fix it

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Using a rock tumbler for cleaning up dirty rocks has become a widespread hobby. Most don’t realize how the art of old polishing rocks is. This is nothing new. Countless people are collecting rocks and stones from their local water sources, parks, or from their yards trying to uncover the hidden beauty under all the grit and dirt. It has become the most satisfying transformation to watch. Of course, it’s never fun when your tumbler starts to leak. 

If your rock tumbler is leaking, then there might be some grit or debris clinging to the rim of the lid. It could also be grit on the recessed part of the barrel where the cover sits. The water can escape in tiny spaces produced by these particles. There are many other reasons for your tumbler to be leaking.

There are more reasons why your rock tumbler may be leaking, but the build-up of grit is the more likely one. It is essential to keep the water inside the barrel to clean the rocks properly to produce beautiful results.

Since there are different reasons your barrel or lid could be causing leaks, there are many ways for these issues to be resolved. Here are a few reasons why your rock tumbler may be leaking and how to fix it.

If you are interested in checking out the best rock tumblers you can find them by clicking here (Amazon link).

Why is my Rock Tumbler Leaking?

Why your rock tumbler leaks and how to fix it
Why does your rock tumbler leak and how to fix it?

These machines are used to smooth and polish the rocks you find at local parks, beaches, or in your backyard. They hold popularity in the jewelry industry as well as crafts, and lapidary hobbyists.

Starting with a rough piece of rock or stone, you can turn it into a beautiful, high-quality jewelry stone. Just like any other machine that is shaping and smoothing out material like rocks or minerals, they can leak or become damaged.

There are many reasons why your tumbler is leaking during the spin—the point of tumbling rocks ins to keep everything inside so that you have a successful result. So, water leaking out is not a good thing.

When the barrel is filled with water, rocks, and abrasive grit, it is placed on the motorized machine that spins the barrel to tumble the rocks inside. As they tumble, they grind against one another with the particles of the grit caught between them.

The grit is like sandpaper. It smooths the surface of the rock. With the constant tumbling, scraping against the barrel, and grit, the rocks are rounded, reducing the sharp edges of the stones and smooths them out.

Troubleshooting a Rotary Tumbler

Due to the rocks, sand, and water continually spinning for two weeks or more, this can cause damage to the barrel. The stones tend to bounce off each other into the top of the lead, which could cause the lid to crack or maybe create a hole.

These barrels and lids are durable, but the more the tumbler is used, the weaker it becomes. Yes, these tumblers can last years, but there are a few bumps along the way.

These are a few troubles you may run into when using a rock tumbler and how to fix them. These tumblers are called Rotary Tumblers.

Particles Are Stuck on the Lid or Rim

The most probable reason your tumbler is leaking is that particles like grit or debris can be lodged on the rim of the lid or on the lower part of the barrel where the top sits. Water can escape in the tiniest of spaces created by the particles stuck.

When changing the water or changing the type of sand after a week of continuous spinning, particles can get lodged in the rim, creating little space that water can sneak through.

When you go to change anything in the barrel, before closing it up again, check the rim. Doing this before putting it back on the motor will save you a lot of time in the long run.

How to check for particle build-up before putting the contents back into the barrel, check the rim, and clean the barrel. Methodically rinse and rub the barrel until every piece of grit and rock has been removed. Use a toothbrush and thoroughly cleanse the edges of the barrel lid and where the cover sits.

Make sure everything is removed before putting your rocks and grit back inside; if one speck of gravel or stone is left behind, you will need to repeat these steps.

To prevent this from happening in the future, be sure to spend at least thirty seconds cleaning the edge of the barrel and the side of the lid every time you change your tumbler. This can result in fewer leaks.

Lid Not Properly Seated

Sometimes the problem is as simple as the lid isn’t correctly sitting. When the lid is seated or secured by the retainer ring or the threaded nut, it is either not straight or not firmly against the sealing surface of the barrel. A particle build-up or rough edges could cause this.

Like above, check the rim; make sure that there are no lingering particles on the side. Also, because the rocks and grit are continuously spinning, this can cause rough edges against the lid of the barrel.

Another reason why sharp edges may become trouble is if the barrel is dropped or scraped against a sturdy surface.

Again, these barrels are durable to last years, but they need to be treated with care. This will cause the lid to sit wrong on the barrel, which will make it leak.

To prevent the lid from sitting wrong on the barrel, check the rim. Make sure there are no particle build-ups or rough edges. Do this before putting the contents back into the barrel. Then return the rocks and grit into the barrel and securely tighten the lid. Make sure it sits evenly and tightly.

Rough Edges or Cracks on the Lid

Depending on what your barrel lid is made of, it can become banged up with lots of use. If your lid is made of plastic or fiberboard, they are easy to damage when dropped or scraped. Tumblers need to be cared for, but things happen, of course.

The rubber retainer rings seem to be the most durable to keep the lid tight, and it prevents them from becoming damaged. The rubber becomes like a bummer for the lid against the barrel and the rocks against the rim of the barrel. It keeps everything together and working cohesively.

You can fix rough edges by lightly sanding them down. You don’t want to sand too much; you don’t want to round the sides of the lid. Give it a very gentle wipe on the upper and lower edges of the rim.

You can find these rough edges by taking a cloth over your finger and feeling around the rim; if the fabric snags on the material, then you may have to sand that down.

Wash the lid and barrel before continuing the spin. If the barrel is still leaking, try sanding it down more, or if the lid is damaged or poorly cracked, you may have to purchase a new lid. These are durable barrels, but over time they do become weaker.

The Lid is Not Secured Tightly

Some of the tumbler lids are secured by a rubber retainer ring or a wing nut. When these are not tight enough, they will leak.

The rubber is like an elastic seal, like a rubber band. It keeps the barrel and lid stay together, tightly as it spins. But just like rubber bands, they can snap and become overstretched.  This will cause leaks, and more damage to the barrel if ignored.

Some of the tumbler lids are secured by a rubber retainer ring or a wing nut. When these are not tight enough, they will leak. The rubber is like an elastic seal, like a rubber band. It keeps the barrel and lid stay together, tightly as it spins.

But just like rubber bands, they can snap and become overstretched.  This will cause leaks, and more damage to the barrel if ignored.

Worn Out Lid

This primarily happens when barrels have a plastic lid. A barrel can roll for over two weeks, with multiple changes of water and grit week by week.

Depending on the size of the barrel, there are more than a few ounces of rocks inside it. This will cause a lot of wear and tear on the lid itself. It is natural for the lid and rubber retainer ring to become worn out.

While the tumbler spins, the grit and rough scraping against the lid can cause damage after too many uses. This is natural. The rocks and grit are supposed to bump and scrape against the lid, but after time passes, the lid can become damaged.

The scrapping of the rocks continuously will cause the center of the top to become thinner and thinner. If not checked thoroughly, this can cause a while, which will result in a mess while it spins.

When this happens, the only thing that can be done is to purchase a new lid. Of course, that is more money out of your pocket, but the original lid should last you a long time. Again, these lids, barrels, and rubber rings are made to be durable.

The Barrel is Damaged

This is also a common problem in barrels that are several years old or barrels that are stored in a hot or cold location.

Try to keep your barrels stored when they aren’t being used in a neutral temperate location. The temperature of where the barrel is stored can age it faster than the continuous rolling rocks.

Also, don’t store the barrel in direct sun; this will cause damage to the barrel. The barrel will become warped and deformed.

A rubber-lined barrel will develop cracks and deform in shape, which will make it hard for it to spin and will most likely leak more.

Detecting cracks, all your need to do is trace your finger around the sealing surface of the barrel, or you can use a cloth.

You might feel the damage with your finger, or the fabric will snag against the rough edges. The damage also may be viable if you flex the rim of the barrel slightly. This can only be solved with a new barrel.

It is rare for a barrel to form a hole at the bottom due to the constant rolling and to scape off the lid. When a lid becomes deformed, or a hole is created in the center, there is nothing more than you can do, you would have to purchase a new one.

TIP: You may have ever wondered if you can reuse your tumbling grit. Well, in some cases this is possible but it has its pitfalls. Read more about reuse in this article:


Can Rock Tumbler Grit Be Reused?


Types of Rotary Tumblers

There are many types of tumblers out there. The tumbler you want to buy depends on your experiences, and if this is going to be a reoccurring hobby. Also, there are tumblers for what budget, ranging from a few dollars to thousands of dollars.

Toy Rock Tumblers

From the smallest and the least expensive, toy tumblers are great for people who are just starting or don’t want to spend a lot of money on a new hobby; they don’t know if they are going to like it.

They are made with plastic bodies and barrels and sell between $40 and $80 online or in a local toy or crafts store; you can also find them on Amazon (Amazon link).

Because of how inexpensive they are, they can only tumble a few ounces of tiny rocks. With the plastic body, this could cause the tumbler to be noisy.

Be sure to store it in a neutral temperature location, or the plastic will warp and deform. This causes the toy rock tumbler not to last long at all. This is not for someone who wants to take this up as an active hobby. It will not last long.

If you just started with tumbling and you are looking for a cheap rock tumbler, I personally recommend buying this rock tumbler by National Geographic (Amazon link). An alternative choice could be this rock tumbler for kids (Amazon link), which is also suitable for children.

Hobbyist Rock Tumblers

Ranging between $70 and $300 depends on the size, these tumblers are created with a metal structure and a superior motor. These tumblers are designed to operate for years.

They are quiet when they tumble the rocks because of the metal barrel lined with rubber, which is a lot better than the toy tumbler. They can spin between 2 to 10 pounds of stones, which is far more than the toy tumbler.

These tumblers are for hobbyists, and it’s in the name! This is a durable, long-lasting tumbler to be used at its highest potential. They are designed to produce enormous amounts of polished stones.

In the 1950s, there were only two brands made: Thumbler’s Tumbler and Lortone. They are still the biggest manufactures today with very little change in the design. Most of their tumblers can be repaired and refurbished with readily available parts.

If you want to buy an advanced rock tumbler, I personally recommend buying one of these two rock tumblers with the best value for the money. The first of them is manufactured by Tumble-Bee and you can buy it here (Amazon link). The second one is manufactured by Lortone and is available to buy here (Amazon link).

Commercial Rock Tumblers

Commercial tumblers are the largest. These are used for commercial use. Most companies that produce polished stones for rock stops, or mineral shops, are more likely to these types of tumblers in their production warehouse than someone’s home.  

They can tumble a few dozen to a few thousand pounds of rocks at once. The cost of these large tumblers is widely expensive, reaching around thousands of dollars.

The commercial tumblers are meant for the mass production of these stones. You will not find anyone’s home or backyard.

Vibratory Rock Tumblers

Vibratory rock tumblers are a little different; since this type of tumbler shakes the contents in the barrel rather than rolls the materials, these are less likely to leak.

They are just as durable as the rotary tumblers and get the job done with less of a hassle, but they aren’t as popular as the rotary tumblers.

It also depends on the shape of the rock you want; round or angular. When the rotary spins the stones, they bump and scabble against the lid and the grit, shaping them into a round, polished stone.

Vibratory tumblers, the shape tends to stay the same because the rocks aren’t being formed by the barrel. They are being smoothed out by the grit and the other stones in the container.

Since vibratory rock tumblers are not so popular, the number of options offered is smaller. If you are interested in this type of rock tumbler, I recommend looking at this type, which has all the required features. You can buy it here (Amazon link).

TIP: Sometimes before you start grinding your stones in a rock tumbler, you need to cut them to a suitable size. But how to do it? I have prepared a complete manual for you, read it here:


Step-by-Step: How to Cut Rocks with Hammer and Chisel


Final Thoughts

Most of these tumblers can last a long time with barely any damage. The leading cause of leaks is with the lid not secured to the barrel, or there are particles stuck on the rim of the lid.

When a barrel or a cover is damaged, your rocks are less likely to come out smooth and polished. This all can be fixed with minimal money spent. It is essential to treat these tumblers with care.

The use of a vibratory tumbler is less likely to leak due to its shaking instead then rolling. When the rotary tumbler is shaping the rocks, it is using the barrel and grit to make them round.

The vibratory tumbler forms the rocks by rubbing them against each other and the grit as well. Both machines have the same result of producing smooth, beautiful stones.

With the popularity of skyrocketing, many are using tumblers to create jewelry and home decorations. Many are using it to produce more money in their pockets.

You can create things your friends and family will be asking where you purchased it. Creating unique pieces can be a conversation starter and provide pride in what you’ve created. They are all not inexpensive, primarily if you use smooth rocks as a source of income.

TIP: Rockhounding is an amazing hobby. But be sure you stay safe during your rockhounding trip. Also, don’t forget to follow the basic rules for undisturbed and pleasant time spent in nature. Read more in the article below:


PRO Tips for Beginner & Experienced Rockhounds + Safety Tips