A cutting insert according to one aspect has a flat plate shape including a first main surface having a polygonal shape, a second main surface located opposite to the first main surface, and an outer peripheral surface located between the first main surface and the second main surface. The cutting insert includes a cutting portion located in regions including at least a corner portion of the first main surface, and a main body portion located in a region other than the corner portion. A thickness of the main body portion is larger than a thickness of the cutting portions, and the main body portion includes a recessed portion or a protruding portion located in the outer peripheral surface thereof.

A cutting insert according to one aspect has a flat plate shape including a first main surface having a polygonal shape, a second main surface located opposite to the first main surface, and an outer peripheral surface located between the first main surface and the second main surface. The cutting insert includes a cutting portion located in regions including at least a corner portion of the first main surface, and a main body portion located in a region other than the corner portion. A thickness of the main body portion is larger than a thickness of the cutting portions, and the main body portion includes a recessed portion or a protruding portion located in the outer peripheral surface thereof.

A cutting insert may include a base and a cutting part. The cutting part may include an upper surface, a first cutting edge and a second cutting edge. The first cutting edge may be located on a first ridgeline. The second cutting edge may be located on a second ridgeline. The upper surface may include a first inclined surface, protrusions and a first upheaved part. The first inclined surface may be located along the first ridgeline. The protrusions may be located side by side in a direction along the first ridgeline on the first inclined surface. The first upheaved part may be located at a side further away from the first ridgeline than the pair of protrusions. The second cutting edge may be inclined downward. An upper end of the first upheaved part may be located above the second cutting edge.

An indexable parting blade has opposite blade first and second sides, a blade peripheral edge, a central index axis, and at least first, second and third insert pockets located along the blade peripheral edge. The parting blade also has first, second and third coolant channels, each forming a coolant path from a corresponding inlet to a corresponding one of the insert pockets. Each coolant channel includes a rake outlet opening out to a rake side of its corresponding insert pocket and a relief outlet opening out to a relief side of that same insert pocket. The inlet corresponding to a given coolant channel is located further from that coolant channel's insert pocket than at least one of (a) the inlet corresponding to a different coolant channel, and (b) the central index axis.

An indexable parting blade has opposite blade first and second sides, a blade peripheral edge, a central index axis, and at least first, second and third insert pockets located along the blade peripheral edge. The parting blade also has first, second and third coolant channels, each forming a coolant path from a corresponding inlet to a corresponding one of the insert pockets. Each coolant channel includes a rake outlet opening out to a rake side of its corresponding insert pocket and a relief outlet opening out to a relief side of that same insert pocket. The inlet corresponding to a given coolant channel is located further from that coolant channel's insert pocket than at least one of (a) the inlet corresponding to a different coolant channel, and (b) the central index axis.

A shank for a tool bit employing an offset arrangement is provided, the shank being able to respond to various types of machining through replacement of heads and having a structure to save time and steps necessary for such replacement of the heads. A cutting tool having such shank is also provided.

A shank 53 of a head-replaceable cutting tool has at least one head attaching part 53A, 53B that is arranged off-center relative to an axis 53X of the shank 53. The axis 53X of the shank 53 corresponds to an axis extending in a longitudinal direction of the shank 53, and the head attaching part 53A, 53B may be arranged so as to be off-center in a direction perpendicular to the axis 53X.

A shank for a tool bit employing an offset arrangement is provided, the shank being able to respond to various types of machining through replacement of heads and having a structure to save time and steps necessary for such replacement of the heads. A cutting tool having such shank is also provided.

A shank 53 of a head-replaceable cutting tool has at least one head attaching part 53A, 53B that is arranged off-center relative to an axis 53X of the shank 53. The axis 53X of the shank 53 corresponds to an axis extending in a longitudinal direction of the shank 53, and the head attaching part 53A, 53B may be arranged so as to be off-center in a direction perpendicular to the axis 53X.

A method for cutting a groove of a predetermined groove width in a work piece, including the steps of providing a metallic work piece having a peripheral surface; providing a grooving tool including a blade portion having a constant or substantially constant blade width, and an insert having a maximum insert width defined by a main cutting edge; selecting the insert width to be greater than the blade width; connecting the grooving tool to a machine interface of a machine tool; rotating the work piece about a rotational axis thereof in a rotational direction; and cutting a groove in the work piece by moving the tool in a feed direction towards the rotational axis of the work piece, such that the groove width is equal to or substantially equal to the insert width and such that a tangential cutting force is directed towards or substantially towards the machine interface.

A cutting insert exhibits superior chip control during grooving and cross feeding. Embodiments include a cutting insert having an upper face, a front face forming an intersecting ridgeline with the upper face, side faces connected to the front face forming intersecting ridgelines with the upper face, a front face cutting edge on the intersecting ridgeline between the upper face and the front face, and side cutting edges on the intersecting ridgelines between the upper face and the side faces. The upper face includes a first portion and an undulating portion on which peaks and troughs are formed continuously in a direction heading away from the front face cutting edge, the undulating portion provided on both lateral direction sides of the first portion. The undulating portion is configured such that the side cutting edges, when seen from the side, each have a continuous undulating shape from the front face cutting edge.

A cutting insert that suppresses softening of joint material in a joint surface between a sintered body and a base body to improve the joint strength, and that enables size reduction of the sintered body, is provided. The cutting insert includes a sintered body having a cutting edge, and a base body having a leading end where the sintered body is joined via a braze material. The sintered body includes a front surface on a leading side, an upper surface connected to the front surface and forming the cutting edge with the front surface along a connecting edge with the front surface, a bottom surface opposite the upper surface, a back surface opposite the front surface, and two side surfaces. The sintered body and base body are joined together in a joint surface including the bottom surface and back surface of the sintered body. The joint surface in side view has a step-like shape with a leading side thereof being lower than a trailing side thereof.