Patent ID: 8801345

Claim:
A cutting method for cutting a work comprising steps of: providing a cutting tool having a cutting edge axis located in a plane perpendicular to a rotational axis of the work such that the cutting tool is oriented toward the rotational axis such that the cutting edge axis intersects the rotational axis of the work; providing an angle changing unit for changing an angle of the cutting edge axis of the cutting tool relative to the work in the plane perpendicular to the rotational axis; detecting an angular position about the rotational axis of the work at which the work has largest dynamic rigidity, the angular position about the rotational axis of the work being detected as an angle between the angular position and an axis perpendicular to the rotational axis and in the plane perpendicular to the rotational axis of the work; adjusting the angle changing unit so that the cutting edge axis of the cutting tool intersects the rotational axis of the work in the plane perpendicular to the rotational axis and is oriented at an angle, set as a set cutting angle, with said axis that is perpendicular to the rotational axis, which set cutting angle is equal to said angle between the angular position and said axis perpendicular to the rotational axis at which the work has the largest dynamic rigidity around the rotational axis of the work; and performing a desired cutting operation in which the cutting tool cuts the work that is rotating around the rotational axis while maintaining the set cutting angle.