Using Local Coordinate Systems for Dimensional Analysis in the Machining

The article considers the implementation of the attached coordinate systems for machining at CNC machines. The main objective of this study is to suggest the improvements of processing accuracy. The problem arises when the machinable surface does not belong to a technological base. We offer the method based on preliminary measurement of workpiece dimensions. Further, the coordinate value enters into a CNC unit. The NC program uses the local coordinate systems, which are linked with measured dimensions of selected surfaces. In this case, the machining accuracy does not depend on errors connected with previous processing stages. Local coordinate systems can be effectively used for machining “rotary body”-type components at turning CNC machines or for machining conditions of box-like parts at milling CNC machines. We also offer the special device for adjustment “0” point outside a machine tool. As a result, the proposed method allows for a dimension chain shortening and accuracy improving.