PURPOSE: To prevent vibration and resonance, to facilitate high speed feed, and to reduce damage of a cutting edge, by a method wherein the tip positions of cutting edges are aligned in a state to provide a difference in stage in an axial and a radial direction, and an outer peripheral cutting edge angle, a rake angle, and a difference in stage are orderly varied.

CONSTITUTION: A difference 7 in stage in an axial direction between adjoining cutting edges 1, 2, 3, 4, and 5 mounted to a cutter body 6 is set to, for example, approximate 0.5W3mm, the difference 8 in stage in a radial direction is set to approximate 0.2W1mm, and an outer peripheral cutting edge angle 9 is changed to approximate 45W1°. The axial rake angle and the radial rake angle of the cutting edge having a maximum size in a radial direction are set to a low value, and those of the cutting edge having a minimum size in a radial direction are set to a high value. Thus, since the cutting edges are not arranged in the same manner, conditions of the cutting edge during cutting are all differed from each other.