Sanding is an operation that is part of the vast set of surface finishing mechanical processes and is useful for finishing materials. More precisely, grinding is a first processing step that allows you to rough and remove sharp edges, burrs or residues from casting, molding or welding from the metal article. It is carried out through abrasive belts and flap wheels through the use of semi-automatic or hand-operated machines. The processing initially involves the use of coarse-grained abrasives to then use increasingly finer ones, until reaching the desired level of surface roughness. The grinding phase is one of the most important surface processes as regards the processing of stainless steel, iron, brass, copper and aluminum. In this phase, the operator must use maximum precision in order to obtain a uniform work surface, ready to be used for subsequent processing. After a detail has been sanded, it can be subjected to subsequent satin or polishing operations in order to further enhance the qualities of the metal. In any case, prior to any other surface processing or painting operation, grinding represents an indispensable and necessary operation.