A cutting insert for parting off a metal work piece includes an elongated body having a top surface, a bottom surface, a first lateral surface, a second lateral surface connecting the top surface and the bottom surface at one lateral side each, a front surface connecting the first and second lateral surfaces, the top surface and the bottom surface, a longitudinal axis extending axially rearward from the front surface in a central plane, and a cutting head having a cutting edge. The cutting edge is formed at an intersection between the front surface and the top surface. The cutting edge includes a leading cutting corner at the first lateral side surface and a trailing cutting corner at the second lateral side surface. The trailing cutting corner is located axially rearward of the leading cutting corner. The cutting edge has a rearmost point located axially rearward from the trailing cutting corner.

A cutting insert and a cutting tool assembly for cutting a workpiece. The cutting tool assembly includes a cutting insert having an upper surface that has a quadrilateral shape so as to include first to fourth insert corner portions, and a shim configured to support the insert. The insert includes an upper surface and a lower surface on which first to sixth inclined mounting portions are respectively formed. The shim simultaneously supports the first to third inclined mounting portions, or simultaneously supports the fourth to sixth inclined mounting portions.

A cutting insert and a cutting tool assembly for cutting a workpiece. The cutting tool assembly includes a cutting insert having an upper surface that has a quadrilateral shape so as to include first to fourth insert corner portions, and a shim configured to support the insert. The insert includes an upper surface and a lower surface on which first to sixth inclined mounting portions are respectively formed. The shim simultaneously supports the first to third inclined mounting portions, or simultaneously supports the fourth to sixth inclined mounting portions.

A rotary drilling tool (10) has a cutting head (12) with at least one tip (22) and a front-facing main cutting edge (24) defining a maximum diameter (D) of the cutting head (12). The cutting head (12) has an undercut (38) with a radially inwardly springing ledge (44) with a rear-facing blade (42) provided for cutting when pulling the rotary drilling tool (10) out of a workpiece. Furthermore, a method is provided for producing a through-hole in a workpiece by means of such a rotary drilling tool (10).

A cutting tool includes a two-way indexable cutting insert retained in a tool holder by a clamping member. The cutting insert has a tetrahedral basic shape and includes two cutting edges at opposite ends of thereof. The insert holder includes a forwardly located mounting portion that includes three spaced apart mounting jaws which together define an insert receiving pocket having a pocket opening. The clamping member is attached to the insert holder body so that a clamping portion of the clamping member protrudes into the pocket opening. When the cutting insert is releasably attached to the insert holder in a fastened position of a cutting tool, the cutting insert is located in the insert receiving pocket and clampingly engaged therein by the clamping portion.

A cutting tool includes a two-way indexable cutting insert retained in a tool holder by a clamping member. The cutting insert has a tetrahedral basic shape and includes two cutting edges at opposite ends of thereof. The insert holder includes a forwardly located mounting portion that includes three spaced apart mounting jaws which together define an insert receiving pocket having a pocket opening. The clamping member is attached to the insert holder body so that a clamping portion of the clamping member protrudes into the pocket opening. When the cutting insert is releasably attached to the insert holder in a fastened position of a cutting tool, the cutting insert is located in the insert receiving pocket and clampingly engaged therein by the clamping portion.

To provide a cutting insert such that a tool body can sufficiently hold the cutting insert even if one of cutting parts is broken. The cutting insert includes two side surfaces opposed to each other, a fixing hole passing through the centers of the two side surfaces, and an outer circumferential surface that is disposed between the outer circumferential edges of the two side surfaces and are connected to the outer circumferential edges of the two side surfaces. The outer circumferential surface includes four cutting parts, a first outer circumferential surface part that is disposed between the first cutting part and the second cutting part, and a second outer circumferential surface part that is opposed to the first outer circumferential surface part and is disposed between the third cutting part and the fourth cutting part. In a side view of the side surfaces from the axial direction of the fixing hole, the first outer circumferential surface part and the second outer circumferential surface part each have the center recessed toward the fixing hole, and a virtual arc having the same diameter as the diameter of the circumcircle of the cutting insert is in contact with two points on each of the outer circumferential surface parts.