Tap to Read ➤

Types of Sandpaper

Renuka Savant Aug 31, 2020
Your walls need repainting? Furniture lacking luster? Need to scrape the rust off that old car? All you want now is the right kind of sandpaper that gets the job done. Here's the dope on all sorts of sandpapers out there.
Sandpapers are things that we sometimes tend to take for granted. Some of us have also committed the folly of making use of any variety available at home, because all sandpapers are ultimately sandpapers, aren't they? Yes, they are, but each one has its own purpose.
So, when you use the wrong type, either you won't be able to do any sanding, or worse, leave scratches on the surface. Some dilemma, this. And when you get down to the task, you'll have grit size, material, backing adhesive, abrasion... so many things that must be considered while choosing the right kind of sandpaper that fits your needs.
Confused? Fret not, as we bring you a comprehensive guide on different types of sandpapers available in the market and their uses.

Characteristics and Types of Sandpaper

Surface Material

This refers to the material that forms the surface. There are four commonly found materials
  • Aluminum Oxide is a very popular type that can be used on metals as well as wood. It is also available in all kinds of grits.
  • Garnet usually suits wood. It is the traditional sandpaper as the surface comprises actual sand particles. The level of coarseness is lower than aluminum oxide, making it less durable.

  • Silicon Carbide, like aluminum oxide, is available in all types of grits and is extremely coarse. You will find it handy while wet sanding any surface. It is used to cut metal, plastic, fiberglass and remove paint. However, it tends to wear out faster.wood. They form a part of sander belts most of the time.
  • Ceramic is the hardest of all the sandpapers available in the market, and the most expensive one as well. It is used in shaving and leveling

Grit

The grit of a sandpaper is the abrasion that you see on the surface. This is the most crucial feature of a sandpaper. They have values that correspond to the level of coarseness; higher the number, smoother the surface, and vice versa. Following are the types of sandpaper available, along with their respective uses.

Sandpaper Varieties

Macro Grits

Grit Grade-Very coarse
Grit Size (µm)-30-36
Compatible With-Metal and Wood
Used For-Removing rust, Shaping wood


  • Grit Grade-Coarse
  • Grit Size (µm)-40-50
  • Compatible With-Metal and Wood
  • Used For-Removing paint, On hardwood floors, Removing scratches
  • Grit Grade-Medium
  • Grit Size (µm)-60-80
  • Compatible With-Wood and Plaster
  • Used For-Preliminary smoothing of walls, Wood sanding, Removing marks
  • Grit Grade-Fine
  • Grit Size (µm)-100-120
  • Compatible With-Metal and Wood
  • Used For-Final use before the finishing
  • Grit Grade-Very Fine
  • Grit Size (µm)-150-220
  • Compatible With-Metal and Wood
  • Used For-Final sanding

Micro Grits

  • Grit Grade-Extra Fine
  • Grit Size (µm)-220-240
  • Compatible With-Wood and Plaster
  • Used For-Sanding between coats, Giving a silky touch
  • Grit Grade-Super Fine
  • Grit Size (µm)-400-600
  • Compatible With-Wood, Plaster, Glass
  • Used For-Sanding of finishes, Wet sanding, Giving sheen
  • Grit Grade-Ultra Fine
  • Grit Size (µm)-800-1000
  • Compatible With-Glass
  • Used For-Polishing

Backing material

Though sandpapers are often 'papers', sometimes different materials like cotton, polyester or rayon may be used in backing. Vulcanized rubber or fiber can be used to make the base as well. In case of very fine grits, mylar is the appropriate material. Why is this important? The backing material indicates the flexibility, thus determining its usage.

Adhesive Used

The glue mainly used to manufacture sandpapers is called 'hide glue'. However, it is not waterproof, if you need to use one for wet sanding; pick one that has a resin bond and waterproof backing material.

Shapes

Sandpapers are available in different shapes to suit your requirements, sheets being the most common. Other shapes include rolls and disks, and cloth backed belts are used to fit in belt sanders. Sandpaper sponges allow sanding in hard-to-reach spots.
Sanding can be made easy just by choosing the right kind of product. And just in case you run out of regular sandpaper, you even have the option of a liquid sandpaper. Hopefully, you are now armed to make the right choice. Before you get down to business, don't forget to put a dust mask on!