Why Your Sanding Belts Keep Breaking (& How To Prevent It)

When you sand regularly, few things are as frustrating as a sanding belt that keeps breaking. Not only does this waste time and materials, but it can also pose a safety risk. 

The good news is that well-made sanding belts rarely break. If you encounter this issue once or twice, the issue is probably with the manufacturer. On the other hand, if it happens a lot, you may want to take a closer look at how they’re being used at your shop. 

Fortunately, there are several steps you can take to prevent sanding belts from breaking and ensure that your sanding projects go smoothly. In this article, the team at Red Label Abrasives will explore the common causes of sanding belt breakage and provide practical tips for preventing it. Red Label Abrasives produces industrial-grade sanding belts with a proprietary joint that won’t break throughout the lifespan of the belt. 

Preventing Sanding Belt Breakage is Important

Keeping your sanding belts from breaking is essential for several reasons: 

• When a sanding belt breaks, it can pose a safety hazard to the user, as the sudden release of tension can cause the belt to whip around and potentially cause injury.
• A broken belt can damage the workpiece, leading to wasted materials and increased costs. 
• Constantly replacing broken belts can be time-consuming and costly - reducing productivity and profitability. 

Sanding belt breakage may also indicate an issue with your equipment or technique, which can lead to a lower-quality finished product. Understanding the problem and adopting the appropriate solution can both improve your output and help your business stay profitable. 

Causes of Sanding Belt Breakage & Solutions

There’s no single cause for sanding belts breaking apart. Instead, the problem usually arises from incorrect usage or the condition of the belt. Below is an overview of some common reasons why your belt could break on you during use.

Improper Use and Handling

When sanding belts are not used or handled correctly, they can become twisted, bent, or otherwise damaged, leading to premature wear and tear and eventual breakage. Here are a few ways improper use can cause sanding belts to break apart:

• Incorrect Installation and Alignment: If the sanding belt is not installed and aligned correctly on the sander, it can cause the belt to run off-center or rub against the housing, leading to excessive wear and breakage.
• Inconsistent Pressure and Speed: Applying too much or too little pressure or varying the speed of the sander too frequently can cause the sanding belt to wear unevenly and break.
• Excessive Force or Bending:Applying excessive force to the sander or bending the sanding belt too sharply can cause it to become distorted or damaged, leading to breakage.

Proper use and handling can go a long way in preventing premature sanding belt breakage. Here are some tips for improving belt longevity:

• Make sure you are using the right type of sanding belt for the material you are working on. For example, open-coat aluminum oxide is recommended for wood while closed-coat aluminum oxide is best for metal.
• Read the manufacturer's instructions for your sanding machine and the sanding belt before use. This will help ensure that you are using the belt correctly and at the right speed and pressure.
• Don't apply excessive pressure to the sanding belt. This can cause the belt to wear out more quickly and break prematurely.
• Use a proper sanding technique to avoid putting unnecessary strain on the belt. For example, avoid sanding against the grain or using a back-and-forth motion.
• Clean the sanding belt periodically to remove any buildup of material. This will help prevent the abrasive particles from becoming dull and reduce friction and heat buildup.

Inadequate Tension

When a sanding belt is not properly tensioned, it can slip or shift on the rollers. If this happens, it can also cause excessive heat to build up in the belt, weakening its backing material and shortening its lifespan. In addition, inadequate tension can cause the belt to flex and bend excessively, which can cause fatigue and cracking in the backing material.

In order to avoid these issues, it is crucial to tension sanding belts as instructed by the manufacturer. This will help ensure that the belt is securely held in place and that it operates without breaking prematurely.

Running the Belt in the Wrong Direction

Some sanding belts are designed to operate in a specific direction, which is usually indicated by an arrow on the back of the belt. If the belt is not run in the correct direction, it may experience excessive stress and wear, which can cause it to break or fail. For example:

• When a sanding belt is run in the wrong direction, the abrasive particles on the belt can be forced against the direction of their orientation, causing them to break or become dislodged from the belt. 
• Running a sanding belt in the wrong direction can cause the belt to become misaligned on the machine, leading to excessive wear and tear on the belt itself. 

To prevent sanding belts from breaking, it is important to always follow the manufacturer's instructions for proper use and direction of the belt. Note: The sanding belts manufactured and sold by Red Label Abrasives are all bidirectional, so this issue won't affect the performance of the product.

Using the Wrong Grit

When the abrasive grit on the belt is not the right size or shape to effectively remove the material being sanded, it can lead to excessive friction and heat buildup. Over time, it can cause the belt to wear out more quickly and ultimately break.

For example, using a grit that is too fine for the material being sanded may cause the belt to heat up, clog with material, and eventually break. Conversely, using a grit that is too coarse may cause the belt to cut too deeply and create excessive heat and friction, leading to belt failure.

Choosing the right abrasive grit for a sanding project depends on several factors, including the type of material being sanded, the desired finish, and the level of material removal required. Here are some general guidelines to help you choose the right abrasive grit:

• Coarse Grits (36-80):Use coarse grits for heavy material removal, such as smoothing rough wood or removing old paint or rust.
• Medium Grits (100-150):Medium grits are used for intermediate material removal and surface preparation, such as sanding between coats of paint or primer.
• Fine Grits (180-240):Use fine grits for light material removal, such as sanding between coats of varnish or lacquer.
• Very Fine Grits (320-600):Use very fine grits for final finishing and achieving a smooth, polished surface.
• Ultra-Fine Grits (800-1200): Use extra fine grits for achieving an ultra-smooth, polished surface, such as on automotive surfaces or fine woodworking projects.

Keep in mind that the grits ranges mentioned above are general guidelines and may vary depending on the specific material and project. 

Using the Wrong Backing 

There are several types of backing materials used in sanding belts, including cloth, paper, and film. Each type has different characteristics that make it suitable for certain applications. For example, cloth-backed sanding belts are generally more durable and tear-resistant than paper belts, making them a better choice for heavy-duty sanding tasks.

If the wrong backing material is used for a particular application, the belt may not be able to withstand the stresses and forces generated during use. For example, if a paper sanding belt is used for a heavy-duty sanding task, the backing material may not be able to provide the necessary support and stability, causing the belt to tear or fail. When choosing belts, always keep the correct backing in mind.

Low-Quality or Worn-Out Sanding Belts

A low-quality belt may be made from inferior materials or poorly constructed, resulting in a higher failure rate. Worn-out belts, on the other hand, may become frayed or damaged over time, weakening their backing material and making them more likely to break.

In both cases, using low-quality or worn-out sanding belts can result in increased friction and heat buildup, causing the belt to wear out more quickly and break. It can also impact sanding performance, as the abrasive particles on the belt may become dull or worn and be less effective at removing material.

To avoid these problems, be sure to use high-quality sanding belts designed to withstand the demands of the sanding job at hand. It is also important to replace worn-out belts regularly and to monitor the condition of the belts during use to ensure that they are still in good working condition. 

Proper Storage is Also Important

Improper storage can cause your belts to degrade and break down prematurely. Here are some tips for correct storage:

• Keep Sanding Belts in Their Original Packaging:The original packaging can help to protect the belts from dust and debris until you’re ready to use them.
• Store Belts Vertically:Hanging the belts vertically can help prevent them from becoming deformed or damaged over time.
• Don't Expose Belts to Moisture or Humidity: Moisture can cause sanding belts to warp or become damaged over time. Store them in a dry area with good ventilation.
• Keep Belts Away From Heat Sources:Heat can cause the adhesive on the belts to break down or become less effective. Store them away from heat sources like radiators or hot pipes.

Get Quality Sanding Belts From a Quality Manufacturer

Sanding belts are an essential tool for any woodworking, metalworking, or finishing project. However, they can be prone to premature breakage, which can lead to wasted time, money, and materials. By understanding the common causes of sanding belt breakage and taking steps to prevent it, you can help ensure that your sanding belts last longer, work more efficiently, and produce better results. 

At Red Label Abrasives, we manufacture sanding belts for a wide variety of applications, from metalworking and woodworking to knife making and automotive. If you need to replace worn-out belts or get advice on how to get the most out of your abrasives, we’re here to help. For more information or to place an order, please call 844-824-1956 or fill out our contact form today.