A separate-edge force coefficients’ calibration method using specific condition for cutters with variable helix and pitch angles combining the runout effect

Abstract

Classical ways of computing cutting force coefficients cannot be used by the cutters with non-uniform helix and pitch angles. So, this paper presents a novel separate-edge-forecast method to compute cutting force coefficients for any kind of flank-end cutter, especially for cutters with non-uniform helix and pitch angles. Using this method, the cutter runout can be combined into the cutting force coefficients without computing the cutter runout parameters. Simultaneously, the method predicts the cutting force coefficients for every cutter edge. Firstly, a series of three-axis machining experiments, which must satisfy the specific condition that only one cutter edge is removing materials at any time, is conducted. Then, the cutting force-curves are divided into N force lobes. Each lobe is assigned to the corresponding cutter edge using an algorithm. Subsequently, the cutter edge and the corresponding cutting force lobe are used to determine the cutting force coefficients. This means N cutter edges have N groups of cutting force coefficients, correspondingly. Finally, in order to verify the validity and correctness of the proposed method, a cutter with non-uniform helix and pitch angle is utilized to predict cutting force coefficients based on which the cutting forces are also computed. The results demonstrate that the cutting forces predicted agree well with the data measured. Simultaneously, it can be observed that the method can predict the coefficients considering the cutter runout effect.