In the workflow of non-standard parts processing, the foundation is what the most important, precision mechanical parts processing is also the same, often first production and processing of fine reference, and then continue to use the fine reference positioning production and processing of other surfaces.
For the box parts, generally speaking, is the main hole for the coarse reference for the production of processing plane, and then use the plane for the production of fine reference for the processing of hole system; for shaft parts, generally are the outer circle as a coarse reference for processing the center hole, and then the center hole for the fine reference for the production of processing the outer circle, end face and other surfaces. If there are several fine benchmark, it should be based on the sequence of benchmark conversion and further improve the basic principles of processing accuracy to specific arrangements for the production and processing of the base surface and the main surface.
The specific working principles of non-standard parts processing can be divided into four levels.
The main surface of the part is generally processing accuracy or surface quality requirements are relatively high surface, their production and processing product quality good or bad to a whole part of the product quality has a great impact, its processing procedures are often more, so should first specific arrangements for the production and processing of the main surface, and then the other surface production and processing moderate specific arrangements in the middle of their cross. Usually the assembly base surface, work surface, etc. as the main surface, and the keyway, fastening with the light hole and screw hole as a secondary surface.
