Evaluation Indicators of the Runout Effects on Milling Forces and Regenerative Stability

Abstract Runout is an unavoidable phenomenon accompanying milling processes, which may significantly affect the cutting forces and the regenerative stability. Since the influences of runout are closely related to cutting conditions such as tool structure, feed per tooth, depth of cut, etc., it is improper to evaluate the influences merely by the runout parameters themselves. In this paper, the runout values and the process parameters are jointly analyzed to study their effects on cutting forces and regenerative stability of milling processes with variable pitch and variable helix tools. Afterwards, two simple indicators, i.e., the process indicator and the signal indicator are presented to estimate the runout effects under various cutting conditions. Numerical simulations and cutting experiments verify that the proposed indicators are feasible, though not perfect, ways to evaluate the runout effects.