Soichi Ibaraki, Kyoto University

On contour-parallel tool paths that are often used in the machining of dies and molds, there are many regions where the tool is subject to significant variation of cutting forces. Particularly in finishing processes, such a variation of cutting forces often degrades machining accuracy and surface finish. This paper proposes an algorithm to generate contour-parallel tool paths that maintain constant cutting engagement angle throughout any given two-dimensional contour geometry. By maintaining the cutting engagement angle constant, the cutting force can be regulated approximately constant under constant feedrate, which potentially improves the machining accuracy in a significant manner. The validity of the proposed tool path generation schemes is investigated by preliminary machining experiments on hardened steel by using a straight end mill.