Glossary of Sandpaper Terms

A

Abrasive: A substance which is used for sanding, grinding and/or polishing. Includes natural materials such as Emery, Garnet, Flint and Crocus and the manufactured materials Aluminium Oxide, Silicon Carbide and Zirconia.

Aluminium Oxide: An abrasive produced through the fusion of mineral bauxite. It is the most commonly used abrasive grain for sadning and grinding of wood and metal due to its strong properties. It is generally brown or red in color. 

Alumina Zirconia: Commonly refered to as Zirconia. High performance alloyed abrasive formed by zirconia deposited in an alumina matrix. This grain is ideal for grinding and sanding of metal and hardwood. 

Antistatic: Special coated abrasives for woodworking which reduce the buildup of static electricity and permit the sanding dust to be collected more efficiently by the dust control system.

B

Backing: A flexible or semi-rigid material to which abrasive grain is bonded by an adhesive. Commonly used backings for coated abrasives include paper and cloth.

Back-Up Pad: A pad which supports the disc during the grinding operation and is normally the same diameter or slightly smaller than the sanding discs. Usually a rubber or composition type material to which an abrasive disc is attached.

Butt Join (Belt): Two pieces of coated abrasive butted together, with no overlap, to form a joined belt. A very strong, thin, reinforced tape is used on the back of the butt joint to hold the belt together.

C

Coated Abrasive: Product comprised of three basic elements: a flexible or semi-reigid backing to which abrasive grains are bonded by an adhesive.

Conveyer Belt: Usually an endless belt configuration that positions, holds, moves, and finally clears workpieces through the abrasive heads on a sanding machine.

Contour Sanding: The sanding of items that have an irregular shape.

Conveyer Belt: A belt that positions, holds, moves and clears workpieces through the abrasive heads on a sanding machine. Take a look at our Conveyer Belts.

Cutting Rate: The amount of material removed by a coated abrasive from the workpiece, per unit of time.

D

Disc: A round, flat-coated abrasive product with or without a center clamping hole. It is affixed to a rotating, oscillating plate, or back-up pad for portable or stationary grinding.

Drum Sander: A power tool used for sanding wood. An endless loop of sandpaper is moved at high speed by an electric motor.

F

Finish: The quality of the surface finish that is produced through sanding or polishing.

Finish: The appearance of small bubbles in a wood finish that is usually caused by silicon contamination.

G

Graphite: A chemically inert variety of carbon with a metalic luster that is used as a friction-reducing material. Take a look at our Graphite Slip Cloth.

Grit: The designation used to describe abrasive grain size. It reflects the number of the smallest openings per linear inch in the screen through which the grain will pass.

H

Hook & Loop: VELCRO® is the registered trademark of a company that produces Hook & Loop fasteners. The "Loop" is on the backing of the sandpaper, whether that backing is paper, film, cloth or mesh. The "Hook" is on the back-up pad of an orbital or random orbital sander, the faceplate of a disc sander and the face of a sanding block, to name a few examples. ​

M

Micron: A unit of measure used to compare abrasive grain. Take a look at our Abrasive Conversion Chart to compare different grading scales.

O

Open Coat: A coated abrasive product where the abrasive grain covers approximately 50-70% of the coated side surface. Open coat abrasives help to reduce clogging when sanding materials such as softwoods or paint.

P

P Grade: The P Grading Scale refers to the European grading system of F.E.P.A for coated abrasive grain.

Polyester: A synthetic cloth material that is commonly used as a backing for coated abrasive products. It is tear and split resistant.

PSA: Stands for Pressure Sensitive Adhesive. An adhesive that is applied to the backing of caoted abrasives which permits the easy product application and removal to and from back-up pads.