The present disclosure can realize further prevention of a mounting mistake caused when a cutting insert is mounted on an insert seat is implemented by voluntarily improving a structure around the insert seat in particular. An insert mounting part has a shape including a bottom surface, a constraint surface that comes into contact with at least a part of a constraint target surface formed as a surface of a peripheral side surface of the cutting insert inclining with respect to an upper surface or a lower surface, an evacuation part that allows evacuation from the constraint surface hedging a cutting edge of the cutting insert, a first protrusion area that extends hiding a part of the upper surface or the lower surface of the cutting insert, a relief part that is formed at a part that a corner part of the cutting insert approaches so as to hedge the corner part, and a second protrusion area that extends from an upper side of the relief part so as to cover the part of the upper surface or the lower surface of the cutting insert mounted on the insert mounting part.

A rotary cutting tool having a disk-shaped cutting body with a plurality of identical insert receiving pockets, and an equal number of indexable cutting inserts removably retained therein, having opposing upper and lower surfaces and opposing first and second insert end surfaces. First and second cutting edges are formed at the intersection of the upper surface and the first and second insert end surfaces, respectively. Circumferentially adjacent cutting inserts have a different one of their first and second insert end surfaces in contact with an insert receiving pocket back wall. First and second planes are equidistantly offset from opposite sides of the cutting body, the first plane only intersecting the first cutting edge of every circumferentially alternate cutting insert and none of the second cutting edges, and the second plane only intersecting the second cutting edge of every circumferentially alternate cutting insert and none of the first cutting edges.

A milling insert includes a first axial face, a second axial face, a first radial face, a second radial face parallel with the first radial face, a cutting face, and a generally V-shaped seating face formed with a first seating surface and a second seating surface. The first axial face defines a secondary clearance surface that is at least partially axially recessed from the first axial face and oblique to the first radial face. The first seating surface and the second seating surface are formed at an angle substantially equal to a radial rake angle when the cutting insert is mounted in the insert seat of the milling cutter. As a result, the seating face produces at least one seating surface that is substantially perpendicular to the tangential cutting force, F.sub.T, thereby reducing movement of the insert when tangentially mounted in the insert seat of the milling cutter.

A double-sided tangential cutting insert comprising a pair of cutting rake faces, a pair of major side surfaces and a pair of opposing minor side faces each having a twisted convex shape. Each of the cutting rake faces is defined between a pair of main cutting edges, a pair of full nose cutting edges, and a pair of opposing convex minor cutting edges. Each of the minor side faces is defined between one of the convex minor cutting edges at one of the rake faces and one of the convex minor cutting edges at the other one of the rake faces wherein, at each minor side face, a ridge line interconnects an apex of the convex minor edge at the one of the rake faces and an apex of the convex minor cutting edge at the other one of the rake faces. Other variants and embodiments are broadly contemplated herein.