Presently, the precise parts and fittings machining develops very fast, and this makes product requirements in the precise parts and fittings machining become more precise and complex. For the precise parts and fittings machining, precision is very high and shape is more complex. What revolutions have been brought to the precise parts and fittings machining?
　　1. Precise machining greatly improves the material machinability. The machinability of work piece material does not have directly relationship with its toughness, brittleness, hardness, strength and so on any longer. Presently, such many methods as electric spark, electroanalysis, laser and so on have been used for machining and manufacturing cutter, tool, drawing mould and so on. In past, the diamond, hard alloy, hardened steel, quartz, glass, ceramics and so on are very difficult to be machined. Compared with un-hardened steel, it is easier to machine hardened steel with electric spark, wire-electrode cutting.
　　2. Precise machining changes the part typical technological line. For traditional machining, except grinding, other cutting and machining, forming and machining must be arranged before the quenching and thermal treatment, which is a technological standard that must be obeyed. After precise and special-purpose machining technology occur, to prevent deformation caused by quenching and thermal treatment after machining, generally it conducts quenching treatment before machining. For example, for electroanalysis machining, electric spark, wire-electrode cutting and so on, it conducts quenching treatment before machining.
　　3. The precise machining can greatly shorten the new product trial manufacture period. Generally for new product trial manufacture, with the precise and special-purpose machining technology, it can directly machine different special and complex conicoid parts, it does not need to design and manufacture relevant cutter, clamp, measuring tool, mould and secondary tool, it can greatly shorten the new product trial manufacture period and accelerate the machining schedule.