DETERMINATION OF THE RADIAL WIDTH OF CUT AND CUTTING MODES IN MILLING

This paper describes a method to calculate the variation in the radial width of cut which occurs when the centre of a milling cutter follows the toolpath segments generated by a postprocessor. This variation is approximated by a stepped curve, thus enabling the toolpath segment t o be divided into subsections, the radial width remaining constant ove r each subsection. The method also enables the cutting modes to be det ermined. The variation in the width of cut is obtained by performing a 2-D Boolean union between the area swept by the cutter when traversin g the current segment and the area already machined. As an example, th e actual widths of cut are calculated for the toolpaths for machining a pocket. The example clearly demonstrates that the actual widths of c ut vary over a wide range and are very different from the value used t o calculate the toolpaths. In fact, for the example considered, slotti ng occurs over 40% of the distance travelled, and only 10% of the actu al widths of cut are approximately equal to the original value used fo r toolpath generation.