When the surface of the part box is machined with different surface roughness, the surface with small roughness is selected to have a small feed speed, and the surface with large roughness is selected for a larger feed speed, and the variability is good. For parts boxes with complex contours, any plane curve can be approximated by straight lines or arcs. Precision machining has circular interpolation function, which can process parts with complex contours. The use of precision machining of the parts box requires the careful use of the operator.