The popular idea of grinding is its use in shaping more or less roughly the edges of cutting tools and in removing fins and other small projections from forgings and castings as a step toward making them smooth.

Developments in recent years in the production of grinding wheels of many shapes and degrees of hardness and the fitting of these wheels to high-grade machines for controlling their motions, have brought into practical use methods of grinding which produce smooth and true surfaces of a degree of accuracy not attainable by any other known means.

Work is now roughed out on the lathe, planer, milling machine and other machine tools and is finished to any desired degree of accuracy better, cheaper and quicker by grinding machines than by other means. This applies to the ordinary as well as to the finest finishing, and it applies also to metals of all degrees of hardness.