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

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The practice of using a rock tumbler to clean and polish dirty rocks has evolved into a popular pastime enjoyed by people from all walks of life. Many don’t realize that this art of polishing stones is a time-honored tradition with roots stretching far back into history.

The allure of uncovering the hidden beauty beneath layers of grit and dirt has driven countless individuals to collect rocks and stones from local water sources, parks, and even their own backyards. Witnessing the transformative process of a rough, unassuming rock emerging as a gleaming, polished gem has become a deeply satisfying experience for hobbyists.

However, the excitement can quickly fade when faced with the frustration of a leaking tumbler, which can damper the enjoyment of this fascinating pursuit.

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 leak, but the build-up of grit is the more likely. Keeping the water inside the barrel is essential to clean the rocks properly and 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 leak and how to fix it.

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

If you want to check out the best rock tumblers, you can find them here (Amazon link).

Why is my Rock Tumbler Leaking?

These versatile machines have gained widespread popularity among jewelry makers, crafting enthusiasts, and lapidary hobbyists for their ability to smooth and polish rocks from local parks, beaches, or even one’s backyard.

Starting with a rough, unassuming piece of rock or stone, a tumbler can transform it into a stunning, high-quality gem suitable for jewelry crafting. However, tumblers can sometimes fall victim to leaks or damage like any other machine designed to shape and smooth materials like rocks or minerals.

There are various reasons why your tumbler might be leaking during the spinning process—an issue that can hinder the success of your rock tumbling endeavors, as the goal is to keep everything contained within the barrel. Water leaking out is definitely not a desirable outcome.

When the barrel is loaded with water, rocks, and abrasive grit, it is securely placed on the motorized machine, which then spins the barrel to tumble the rocks inside. As the stones tumble, they grind against one another, with grit particles caught between them.

The grit acts like sandpaper, smoothing the surface of each rock. Through the constant tumbling action, combined with the scraping against the barrel and the presence of grit, the rocks gradually become rounded, with their sharp edges diminished and their surfaces polished to a smooth finish.

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 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 leaks 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 change anything in the barrel, check the rim before closing it up again. Doing this before putting it back on the motor will save you much time in the long run.

How do you 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.

Ensure everything is removed before putting your rocks and grit back inside; if one speck of gravel or stone is left behind, you must 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.

TIP: Loading your rock tumbler with rocks and grit can be challenging. Find out the complete guide in the article below:
Rock Tumbler Loading: How Much Grit & Rocks Do You Put In?

The lid is 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; ensure no lingering particles are on the side. Also, because the rocks and grit are continuously spinning, this can cause rough edges against the barrel lid.

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 and last for years, but they must be treated carefully. This will cause the lid to sit wrong on the barrel, making it leak.

Check the rim to prevent the lid from sitting wrong on the barrel. 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 easily damaged 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 in keeping the lid tight, preventing them from becoming damaged. The rubber becomes like a bummer for the lid against the barrel and the rocks against the barrel’s rim. 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, 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

A rubber retainer ring or a wing nut secures some tumbler lids. 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 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.

A rubber retainer ring or a wing nut secures some tumbler lids. 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 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 the lid can become damaged after time passes.

The rocks’ continuous scraping causes the top’s center to become thinner and thinner. If not checked thoroughly, this can take a while, resulting 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 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 several years old barrels or barrels stored in a hot or cold location.

Keep your barrels stored when they aren’t used in a neutral temperate location. The temperature at which the barrel is stored can age it faster than 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 shape, making it hard for it to spin and most likely leak more.

To detect cracks, all you 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 may also be viable if you flex the barrel’s rim 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 escape off the lid. When a lid becomes deformed, or a hole is created in the center, there is nothing more you can do; you would have to purchase a new one.

TIP: You may have wondered if you can reuse your tumbling grit. 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 will be a recurring 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 will 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. The plastic body 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 tumbling and are looking for a cheap rock tumbler, I recommend buying this rock tumbler for kids (Amazon link), which is also suitable for children.

Hobbyist Rock Tumblers

Ranging between $70 and $300 depending 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 the metal barrel lined with rubber is much 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 for use at its highest potential. They are designed to produce enormous amounts of polished stones.

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

If you want to buy an advanced rock tumbler, I recommend buying one of these two with the best value for the money. Tumble-Bee manufactures the first; you can buy it here (Amazon link). Lortone manufactures the second one, which is available 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 likelier to have these types of tumblers in their production warehouse than in someone’s home.  

They can simultaneously tumble a few dozen to a few thousand pounds of rocks. These large tumblers are widely expensive, reaching around thousands of dollars.

Commercial tumblers are meant to mass-produce these stones. You will not find anyone’s home or backyard.

TIP: If you are interested in knowing more about rotary rock tumblers, check out the complete guide in the article below:
Rotary Rock Tumblers: How They Work & Which One Is Best?

Vibratory Rock Tumblers

Vibratory rock tumblers are slightly 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 do the job with less 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.

The shape of vibratory tumblers tends to stay the same because the rocks aren’t formed by the barrel. The grit and the other stones in the container are smoothing them out.

Since vibratory rock tumblers are not so popular, fewer options are offered. 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: If you are interested in knowing more about vibratory rock tumblers, check out the complete guide in the article below:
Vibratory Rock Tumblers: How They Work & Which One Is Best?

Final Thoughts

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

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.

Using a vibratory tumbler is less likely to leak due to its shaking instead of rolling. When the rotary tumbler shapes the rocks, it uses the barrel and grit to round them.

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

With the popularity skyrocketing, many use 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 ask where you purchased. Creating unique pieces can be a conversation starter and provide pride in your creations. They are not inexpensive, primarily if you use smooth rocks as a source of income.

TIP: Even if you are a beginner or a professional, you are always curious about which rocks can tumble together. Check them out in the article below:
What‌ ‌Rocks‌ ‌Can‌ ‌Be‌ ‌Tumbled‌ ‌Together:‌ ‌Complete‌ ‌List‌ ‌With‌ ‌Tips‌