Sell With Us
Workshop Classes
  • 5% Off Marketplace Wide!

Sand Smarter Not Harder

Sand Smarter Not Harder

Sand smarter, not harder. Our goal is simple, to offer the best quality abrasive discs for almost any surface. Only the best brands at the best prices.

Different Types of Abrasive Discs

When considering what is the best sanding disc to use for a specific job there is an overwhelming range of different discs, grains and grits available on the market. It is difficult to know what to choose for your job. This post will address the most suitable disc to use depending on your requirements. Not only does the density of sandpaper grit make a difference in the success of your sanding project, but the type of abrasive material does, too. The following is a brief description of the more common types of abrasive grains used in sandpaper products.

There are many types, but the five main types of sandpaper grits are: aluminium oxide, silicon carbide, ceramic net and garnet.


Aluminium Oxide: is a popular abrasive, known for its hardness and strength and low cost when compared to other abrasive types. Aluminium Oxide lasts longer than the other kinds of grits since it contains a self-renewing property; because it's the most delicate, it crumbles easily, forming new soft edges. It has low heat retention and low specific heat making it useful in a wide array of grinding and sanding applications. Aluminum oxide occurs naturally in the form of the mineral corundum, but the mineral is not used as a commercial abrasive except as a component of emery. When combined with emery and/or crocus, it produces an abrasive suitable for finishing applications.

Silicon Carbide: (SiC) is a widely used abrasive due to its durability and low cost. Ideal for sanding harder materials such as metals and plastic. It is a synthetic abrasive first developed in the late 1800s. SiC is harder than aluminum oxide, but more friable than fused aluminum oxide grains. Since silicon and carbon are both soluble in steel, silicon carbide is not a effective in grinding steel or ferrous alloys—especially with coarser grit sizes in heavy metal removal applications. Silicon carbide is typically used in applications involving nonferrous metals such as brass, aluminum, and titanium, and for abrading non-metals such as stone, glass, wood, and leather.

Ceramic: abrasive grain is the top of the range in terms of both effective cutting ability and how long the discs will last. In general ceramic is the most expensive and roughest grit. It is extremely tough, sharp, and long-wearing and does not dull quickly because of its extreme density, making it best for aggressive material removal with both wood and all types of metal including Stainless Steel. This makes ceramic discs the best choice for removing stock, and sanding all surfaces in wood or metal. For this reason, ceramic abrasive discs are generally more popular in the more coarse grits. Ceramic abrasives are durable, and lasting longer than both aluminium oxide and zirconia. View Ceramic Discs

Net: The net fabric structure permits the maximum absorption of sanded particles thus providing dust-free sanding and cleaner surfaces. This means a healthier work environment, where less time and effort is needed for cleaning up whilst the worker is protected from the dangerous sanding dust. View Net Discs

Garnet: paper is an example of a glass paper and is created by crushing the minerals to different powder, or "grit," consistencies and adhering the resulting grit to some kind of backing paper or cloth. Old-school woodworkers claim that the naturally occurring mineral produces a “softer” scratch pattern. Their claims may have a few grains of truth.

Different Sanding Grit Sizes:

Sandpaper is measured by its grit size, or number of sharp particles per square inch of sandpaper – the lower the grit number, the courser or harsher the grit. A 24 grit sanding product will be very aggressive in the removal of stock leaving harsh scratches on the surface, as opposed to a 600 grit sandpaper which is designed to remove less material in a way that leaves a smoother finish. You need to choose the grit size of sandpaper depending on the particular job you are trying to accomplish. The higher the number, the smaller the grains and the finer the sandpaper grit. Conversely, lower numbers indicate larger grains and overall coarser sandpaper. Many jobs require you to “go through the grits.” This means you start the project using lower numbered grit and use finer pieces of sandpaper as you progress. Each time you advance to a higher grit sandpaper, you remove the scratches from the previous layer.


Abrasive discs also differ in terms of mounting and special features. For example, hook and loop mounting attaches the abrasive using a hook and loop fabric whereas bore or center mounting use a central hole through which the disc attaches to the integral mandrel, arbor, spindle, or shaft.


Materials - Everyone Loves Good Backup:

The backing material that the abrasive is adhered to is almost as important as the grit. Abrasive discs are constructed using one (or more) types of backing. Backings are the flexible material to which abrasive grain is adhered to make coated abrasives and similar products. Typical backing materials include cloth, fiber, film, foam, sponge, and metal. Cloth discs consist of a woven fabric such as cotton and are used in aggressive applications such as abrasive planing. Fiber discs are denser than cloth and contain vulcanized or chemically treated cotton or cellulose fibers; however, fiber discs may curl under humid conditions. Film discs use abrasive grains on plastic film, while foam and sponge discs use abrasive grains bonded onto a foam layer, sponge, felt, or other soft, resilient materials. Similarly, metal discs use abrasive grains bonded onto a metal backing such as aluminum or brass. Other types of disc backing include paper, screen, non-woven, or aggregate materials.

Paper: Due to the fine surface of paper, a consistent finish is produced. Paper weights include A, B, C, D, E and F weights with A being the lightest and most flexible and F being the heaviest and least flexible. A, B, C and D weight papers are used for hand sanding and light mechanical operations in the form of sheets, PSA (pressure sensitive adhesive) and hook and loop discs and sheet rolls. E and F weight papers are primarily used for more aggressive mechanical operations in the form of belts and discs.

Cloth: Cloth backings used for coated abrasives are identified by weight. Cloth backings are filled or “finished” with a variety of materials (glues or resins) to create various backing characteristics, most notably flexibility. Several cloth types are used: cotton, polyester, polyester/nylon and polyester/cotton blends, and rayon. There are three basic weights of cloth: J-weight or “jeans” is the lightest and most flexible. X-weight or “drills” is a heavier cloth that ranges in flexibility, strength and durability and is used on the broadest range of applications. Y-weight is a heavyweight drills cloth used on heavy-duty, high stock removal operations.

Fiber: Vulcanized fiber (cotton fibers which are chemically treated and then pressed under temperature and pressure to form a very durable backing) is used exclusively as the backing for resin fiber discs.

Film: Polyester film backing comes in 3 mil. and 5 mil. thicknesses, which have high strength and surface smoothness. They are used primarily in disc and roll applications requiring consistent surface finish, including powertrain applications.

Foam: Primarily used as backing for sponges, finer grit finishing discs, and buffing and polishing pads for cleaning and moist finishing applications.

Mesh: Mesh matrix backing comprised of thousands of tiny holes allowing for maximum dust extraction.

Why Buy Auto Repairs Direct Sanding Discs?

When quality of finish is of primary importance. We offer a solution for many surfaces and job types to help you get the result you need. Everything from heavy-to-medium stock removal, to fine finishing, to light blending and polishing, sanding discs are available in many shapes, grains, specialty coatings and backing configurations to meet many application needs.