(1) According to the file tooth size, it can be divided into coarse file, medium file, fine file and smooth file. (2) According to the section shape, it can be divided into flat file, square file, round file, triangular file and semicircular file.

3) Plastic files used for dressing, such as assorted files and fine files. Just use a common file after welding. Choose a thick file or a thin file according to the accuracy of your processed products. The hardness of the knife is very high, and there is a golden steel file. When polishing, be careful not to scratch the product, or just scratch the gloss.