Belt Abrasives and How They Differ

Belt sanders are an excellent addition to most coldshops. After a wet saw, a belt sander is one of our most recommended pieces of machinery.

They are excellent for working the edges of pieces, fixing surface blemishes on rounded surfaces, and can even be used to grind flat surfaces with a flat platen addition.

Belt sanders are available as both smaller tabletop models and floor-standing upright models. The larger floor-standing models have more power with larger belts for a faster removal rate and longer belt life, but they take up more floor space area and are costly. The smaller tabletop sanders are perfect for small surface areas but can bog down quickly with larger surface areas or bigger work, and the belts are smaller, so their lifespan is reduced.

But which belts should you use on your belt sander?

With so many belt options available, let's go through the choices and give you an idea of the best use cases.

Silicon Carbide Belts

Silicon Carbide belts are the most common belt for a belt sander.

If you've watched any of our Coldworking 101 videos on abrasives, you'll know that silicon carbide is a sharp abrasive that removes material quickly and efficiently. They are inexpensive and work very well on glass surfaces.

The drawback to a silicon carbide abrasive belt is that it wears very quickly. These belts will start removing glass aggressively when they are new and will wear quickly into a less aggressive running state and continue to degrade from there. This can be advantageous when using belts to get a finer and finer surface, as a worn-out 400-grit silicon carbide belt will give a surface more like an 800 or 1200-grit finish on the glass.

Unfortunately, if you're looking to maintain a consistent grinding surface on the glass, the silicon carbide belts will have to be replaced more often, especially in high use studios. They are inexpensive to replace, though, and easy to use.

Electroplated Diamond Belts

If you find that you're wearing Silicon Carbide belts very quickly in your processes, it might be time to look into an electroplated diamond belt. While these belts are considerably more expensive than Silicon Carbide belts, they also have the added advantage of longevity and consistency.

Where Silicon carbide belts wear very quickly, the electroplated diamond belts maintain their aggressive removal on the glass for the life of the belt. Every time you go to that belt, you'll know exactly how it will grind your glass and the surface you'll get from it. The drawback is you'll oftentimes need to move to another style belt to move the surface to a finer finish, and the upfront costs of the belt are much higher.

The electroplated diamond belts have an extremely long life compared to the silicon carbide.

What about Pre-polish Finishing Belts?

Good question! The Silicon Carbide and Electroplated Diamond belts are excellent for shaping and removing material, but what about finishing areas and prepping them for a polish?

Regarding finishing belts, several options that do very similar things to your glass are available. It can be hard to decide which is best for your work.

While we're not going to tell you which belt you should use, we will go over what each belt does to your glass and allow you to choose which is the best choice for your process.

Diamond Resin Smoothing Belts

These belts are made from the same material as our diamond resin flat laps for pre-polishing your glass. In a belt form, they will behave a little differently than they do as a flat lap.

The resin diamond belts will have a longer life than the comparable flat lap version of the material and leave a slightly more aggressive finish on the glass. The removal rate is fast, and the surfaces are clean and easy to polish.

The resin belts will have a rougher final surface on the glass, so it may take longer to polish from these belts, but each step works very quickly and requires little time on the belt.

Cork Belts

Cork belts are an excellent way to clean up glass surfaces after finer grit Silicon Carbide belts like 600-grit

Our Cork belts are pure cork without any embedded abrasive. After fine-grit silicon carbide, a cork belt will give a semi-translucent appearance on the glass with a smooth, even texture that is eye-pleasing and easy to polish from with cerium.

The main drawbacks to cork belts are the longevity of the belt and the price. Cork belts are expensive and have a shorter life span, like Silicon Carbide, so they can be costly if you work with a lot of material.

Trizact Abrasive Belts

One of the best abrasives for finishing work with a belt is 3M's Triazact Abrasive Belts. The abrasive in the belt is aluminum oxide, a rounded abrasive that has a long life and leaves an excellent finish on the glass.

3M's Trizact material is constructed of small pyramids all along the surface of the belt that has fine-grit aluminum oxide embedded into the material. The pyramid structure allows for aggressive work on the surface of your material but with fine grit and less sharp abrasive, so the results are a swift, very clean surface on your glass.

The main drawback to Trizact material is the heat generation created by the pyramidal structure. If you aren't careful, you can create thousands of microfractures in your glass that can cause many headaches to go back and remove. It's important when using Trizact belts to have plenty of water on the surface of the glass and to remove the glass from the belt every so often to reduce the heat buildup on your glass.

There are two types of Trizact material we carry. The 272LA material is a film-backed Trizact in different colors to denote the different grits. These belts will generate heat quickly as they require more pressure to work. The 237AA Trizact material is a cloth-backed belt similar to your standard Silicon carbide belt backing. These require less pressure to work on the glass and will generate less heat while working. They are uniformly grey, so it's important to look at the back of the belt to see which grit you are using.