STUDY ON ACCURACY IN END-MILL OPERATIONS .2. MACHINING ACCURACY IN SIDE CUTTING TESTS

This paper deals with an experimental analysis of machining accuracy in end-mill operations. The accuracy expected by the theory, which is defined by both the static stiffness of an end mill and the instantaneous cutting force, is verified by a series of side cutting tests. The results obtained are as follows. (1) The static stiffness of an end mill analyzed by a transfer matrix method, the instantaneous cutting force estimated in a simple cutting model, and the accuracy determined by these parameters are fairly in accordance with the experimental results. (2) The accuracy decreases with increasing feed, width of cut and helix angle, while depth of cut hardly influences it in usual operations. (3) Using a helical end mill, up milling produces a workpiece cross section with a convex shape and down milling produces one with a trapezoidal shape.