Schmirgelpapier

Schmirgelpapier is a German term for sandpaper, a material used for abrasion, polishing, or surface preparation. It consists of a bonded abrasive grain set on a flexible backing. The abrasive grains are typically silicon carbide, aluminum oxide, garnet, or emery, while the backing can be paper, cloth, or plastic. The binding matrix determines the paper’s softness and durability; tougher backing allows the paper to withstand higher pressure.

Sandpaper is selected by grit size, measured on the West German or American grit scales. Fine grits (e.g., 240 or 320) produce a smooth finish, whereas coarse grits (such as 60 or 80) remove material quickly and are used for shaping or sanding rough surfaces. The grit number typically increases with decreasing particle size; thus a higher grit indicates a finer finish.

Typical applications include woodworking, metalwork, automotive painting, and surface conditioning in construction. In woodworking, a 120 grit surface may be sanded down to 320 for finishing. In metal surfaces, more abrasive grains like aluminum oxide or silicon carbide are preferred for their hardness.

The production of sandpaper dates back to the 18th century with the invention of the "paper-and-grinder" system, later improved in the 20th century by synthetic binders and more uniform abrasive distribution. Modern advances include resin binders, silicon carbide bonded sandpaper, sandblasted edges for edge protection, and environmentally friendly materials such as biodegradable paper backing.

Schmirgelpapier remains an essential tool in manual and industrial finishing processes, offering a balance between efficiency, precision, and control.