Abstract: In this cutting tool with a replaceable cutting head, a cutting head including a cutting edge is detachably attached to a tip end portion of a shaft-like tool main body rotated around an axis in a tool rotation direction. The tool main body and the cutting head are attached to each other when an abutment surface of the tool main body on a tip surface of the tool main body abuts and adheres to an abutment surface of the cutting head on a posterior end surface of the cutting head. A recessed portion and a projecting portion able to be inserted into this recessed portion are respectively formed on the posterior end surface of the cutting head and the tip surface of the tool main body. The recessed portion and the projecting portion are formed to increase in width in a circumferential direction toward an outer peripheral side.

Abstract: In an indexable rotary cutting tool of the present invention, a cutting edge portion of an insert includes a peripheral cutting edge, a bottom cutting edge, a cutting edge of a corner R, and a chamfered surface, a radial rake angle (?) of the cutting edge of the corner R has a negative value in an entire edge length region of the cutting edge of the corner R, and the radial rake angle (?) becomes a minimum value at an intermediate portion located between a pair of boundary points (P, Q) in the cutting edge of the corner R.

Abstract: In an indexable rotary cutting tool of the present invention, a cutting edge portion of an insert includes a peripheral cutting edge, a bottom cutting edge, a cutting edge of a corner R, and a chamfered surface, a radial rake angle (?) of the cutting edge of the corner R has a negative value in an entire edge length region of the cutting edge of the corner R, and the radial rake angle (?) becomes a minimum value at an intermediate portion located between a pair of boundary points (P, Q) in the cutting edge of the corner R.

Abstract: An indexable rotary cutting tool and insert is capable of performing a high-accuracy cutting process with high efficiency. A twist angle of an outer peripheral cutting edge of the tool has a positive value, an axial rake angle of the cutting edge of a corner R of the tool at a boundary point between the cutting edge of the corner R and the outer peripheral cutting edge has a positive value, the axial rake angle of the cutting edge of the corner R at a reference point has a negative value, and the radial rake angle at least between the boundary point and the reference point in an entire edge length region of the cutting edge of the corner R has a negative value. The radial rake angle at the reference point is smaller than the radial rake angle at the boundary point.

Abstract: An indexable rotary cutting tool comprising, a twist angle of the outer peripheral cutting edge having a positive value, an axial rake angle of the cutting edge of the corner R at a boundary point between the cutting edge of the corner R and the outer peripheral cutting edge has a positive value, the axial rake angle of the cutting edge of the corner R at the reference point has a negative value, at least the radial rake angle in a region between the boundary point and the reference point in an entire edge length region of the cutting edge of the corner R has a negative value, and the radial rake angle of the cutting edge of the corner R at the reference point is smaller than the radial rake angle of the cutting edge of the corner at the boundary point.

Abstract: A negative cutting insert having a cutting edge comprising four long-side cutting edge portions for rough cutting and four short-side cutting edge portions for finish cutting, which are connected alternately, thereby being able to conduct rough cutting when attached to a rough-cutting tool body, and finish cutting when attached to a finish-cutting tool body. When such cutting inserts are used for rough or finish cutting and then reattached to a finish-cutting tool body or a rough-cutting tool body, finish or rough cutting can be conducted, thereby using all cutting edges thoroughly.

Abstract: A negative cutting insert having a cutting edge comprising four long-side cutting edge portions for rough cutting and four short-side cutting edge portions for finish cutting, which are connected alternately, thereby being able to conduct rough cutting when attached to a rough-cutting tool body, and finish cutting when attached to a finish-cutting tool body. When such cutting inserts are used for rough or finish cutting and then reattached to a finish-cutting tool body or a rough-cutting tool body, finish or rough cutting can be conducted, thereby using all cutting edges thoroughly.