Emery paper

Emery paper is a type of abrasive paper or sandpaper, that can be used to abrade (remove material from) surfaces or mechanically finish a surface. Operations include deburring, polishing, paint removal, corrosion removal, sizing, etc. This is accomplished by moving the abrasive-coated paper, with some pressure, against the object being processed. Abrasion may be performed by hand, electrically powered, or air powered equipment.

Emery is a naturally occurring rock of impure crystalline aluminum oxide or corundum. The emery is milled and sieved into different mesh sizes. Emery of a certain size range is then bonded to a paper backing to produce emery paper. The larger the mesh size, the smaller the abrasive particles. Smaller particles abrade smaller amounts of material and are used to produce a finer finish.

By the successive use of progressively finer mesh emery paper, near-mirror finishes can be obtained. Water or oil is often used as a lubricant and to float the abrasive debris and worn abrasive away from the work, preventing the build-up of debris in the emery paper. The paper will lose effectiveness if too much debris builds up, a condition known as "clogging."

Originally, emery paper was made from milled emery rock, bonded or sized to paper often with an animal glue for water resistance. Today, synthetic adhesives are used in place of natural glues and silicon carbide is often substituted for emery. Silicon carbide being slightly harder, and more durable with less tendency to fracture than corundum. The use of emery papers is rare today generally being replaced with silicon carbide papers.

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