What is Sand Paper Made Of?

by Pamela Keene

Overview

Sandpaper is an essential tool that is used in many applications, from your home workshop to the production floor of a manufacturing plant. Sandpaper is made by gluing an abrasive onto a backing material. It originated in China during the 13th century and was made by hand using crushed seeds, shells, sand and parchment. Today, sandpaper is mass produced in a factory and doesn't contain sand at all.
Backing

Heavy paper is used for the backing material of sandpaper sheets and disks. Cloth is used in sanding belts and Mylar or vulcanized fiber is used in sandpaper that needs to have a stiff backing.

Adhesives

Most commercial grade sandpapers use hide glue to hold the abrasive onto the backing. Industrial grade sandpaper and sandpaper used for wet sanding use resin as the adhesive.
Abrasive

Some of the most common abrasives used to make sandpaper are aluminum oxide, garnet, silicon carbide and ceramic. Each abrasive has different properties and can be used to achieve a variety of sanding results.
Aluminum Oxide

Aluminum oxide is one of the most commonly used abrasives. It is self sharpening because, as it is used, it fractures and creates new sharp edges. It can be used to sand any surface.
Garnet

Garnet is a good, economical choice for woodworking. It dulls as it is used instead of fracturing, so it creates a very smooth finish.
Silicon Carbide

Silicon carbide is a hard abrasive that is self sharpening when it is used on a hard surface, such as metal or fiberglass. It can be used for wet or dry sanding.
Ceramic

Ceramic is one of the hardest abrasives used for sandpaper. It is most often used for shaping and sanding off large amounts of wood quickly.