1, divided into: general locksmith file for general filing; Wood file, used for filing soft materials such as wood and leather; Plastic file (assorted file) is used to file small and thin metal parts, and a set of files with various cross-sectional shapes; Knitting file of woodworking saw; Special files, such as flat and arched special-shaped files (special files), are straight and curved.
2. Files are divided into flat files (flat files), square files, semi-circular files, round files, triangular files, diamond files and knife files according to the section shape. Flat file is used for filing plane, cylindrical surface and convex arc surface; Square file is used to file square holes, long square holes and narrow planes; Triangular files are used to file internal corners, triangular holes and planes; Semi-circular file is used to file concave curved surfaces and planes; Circular file is used to file round holes, concave cambered surfaces with smaller radius and elliptical surfaces.
3. According to file types, files are divided into single files and double files. The cutter teeth of single file are inclined at a certain angle with the axis, which is suitable for processing soft non-ferrous metals; The main file and the auxiliary file of the double-edged file are alternately arranged, and are used for processing steel and nonferrous metals. It can divide a wide file into many small pieces to make the file lighter.
4. Files are divided into I ~ V numbers according to the number of main file stripes per 10 mm length, where I is coarse file, II is medium file, III is fine file, and IV and V are smooth files, which are used for rough machining and finishing respectively. The diamond file has no file, but a layer of diamond powder is electroplated on the surface of the file to file hard metal.