Chip thickness analysis based on tooth trajectory for different end milling processes

Instantaneous chip thickness during three typical end milling processes is analyzed in this paper. The tooth trajectory of a milling cutter is a combination of two motions, one is the rotation of the cutter spindle and the other is the feed motion of the cutter relative to work-piece. For simplification traditional chip thickness models always simplify the tooth trajectory as a circle to get approximate results. In this paper, modeling of true tooth trajectory in linear, arc and profile end milling processes is studied. And mathematical expresses for entry and exit angles of tooth, feed per tooth along cutter contact path are derived for undeformed chip thickness modeling. The instantaneous chip thickness of each process based on circular tooth trajectory model is analyzed as well for comparison. Cutting forces under different chip thickness models are also predicted to study the effect of tooth trajectory on milling process simulation.