In hardware and metalworking, bar- or rod-shaped tool of hardened steel with many small cutting edges raised on its surfaces. Files are used for smoothing or forming objects, especially of metal. A file's cutting or abrading action results from rubbing it, usually by hand, against the workpiece. The single-cut file has rows of parallel teeth cut diagonally across the working surfaces. The double-cut file has rows of teeth crossing each other. Rasp teeth are disconnected and round on top; rasp files are usually very coarse and are used primarily on wood and soft materials.
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