Abstract: The invention describes a drill plate with a clamping attachment in a rotatably driven base body, which on one of its end faces forms a centering groove that is open towards the top. A clamping slot extending into the material of the base body is arranged at the bottom of the centering groove. The centering groove is bounded by at least two opposing mounting jaws, with at least two diametrically opposing stop faces arranged in the region of the clamping jaws for providing centering contact with the drill plate. The clamping attachment is formed by a mounting screw which clamps the drill plate in the centering groove (2.3). To improve transfer of the operating torque from the drill plate to the base body and to facilitate handling, at least two centering fins that are diametrically opposed with respect to the transverse center axis are arranged on the drill plate. The centering fins contact corresponding stop faces disposed on the corresponding clamping jaws of the base body.

Abstract: A tool for chip removing machining, including a replaceable cutting insert and a basic body. The basic body includes a rear fixing part, a front supporting part having an insert seat, and a tightening part situated over the support part, and spaced-apart from the front supporting part by a first gap and from the rear fixing part by a second gap. The tightening part is connected to the basic body via a joint. The joint is formed of at least one elastically resilient material portion and has an axis around which the tightening part is pivoted in order to press the cutting insert against the insert seat by a front finger. The rear fixing part includes an internal channel for feed of a fluid in the forward direction through the basic body. The internal channel extends into a second channel inside the tightening part via a channel section that is entirely or partly housed in a bridge which, like the joint, is formed of the material in the basic body, and which bridges one of the first and second gaps.

Abstract: The present invention relates to cutting tools and, more particularly, to cutting tools having inserts and insert-receiving recesses with curved surfaces. The cutting tool includes a toolholder having a recess and an insert adapted to be received in the recess. The recess has a top surface with a curved portion, a bottom surface with a curved portion, and a fixed stop surface. The insert has a top surface with a curved portion, a bottom surface with a curved portion, and a stop surface. The curved portion of the top surface of the insert and the curved portion of the bottom surface of the insert are curved such that they abut against the curved portion of the top surface of the recess and the curved portion of the bottom surface of the recess, respectively, when the stop surface of the insert abuts against the fixed stop surface of the recess. The present invention also relates to a cutting tool kit, a cutting insert and a method for positioning an insert relative to a toolholder.

Abstract: There is disclosed a clamping mechanism for a cutting insert that clamps the cutting insert by inserting the cutting insert into an insert mounting seat. The insert mounting seat is formed in a tip of a holder having a pair of contacting surfaces facing each other, and the cutting insert has a pair of contact surfaces to come in contact with the pair of contacting surfaces, respectively. The tip of the holder is provided with a pair of jaws that is formed with the pair of contacting surfaces, respectively, and that can be elastically deformed relatively in a direction that the contacting surfaces contact the contact surfaces, and a clamping means that elastically deforms the pair of jaws to bring relatively the pair of contacting surfaces close to each other and to separate them relatively from each other.

Abstract: A cutting tool in which a cutting insert is resiliently retained. The cutting insert includes a locating portion and a cutting portion having a rake surface and a relief surface. The locating portion extends from the cutting portion away from the rake surface.

Abstract: A cutting insert for grooving operations having a forward main cutting edge and two opposing side cutting edges extending rearwardly and outwardly from the main cutting edge, each side cutting edge having a variable rake angle.

Abstract: A cutting insert includes a polygonal body having an upper chip surface, a bottom surface and a peripheral edge surface extending therebetween. The peripheral edge surface intersects the upper chip surface to form a main cutting edge. The upper chip surface defines a chip face including a chip former comprising a wall extending downwardly from an elevated plateau to a cutting edge having a plurality of chip forming grooves and a rib formed between adjacent chip forming grooves. The chip former of the cutting insert effectively controls the formation of a chip by forming the chip to a desired shape and guiding the chip to an obstruction that impedes chip flow until the chip breaks.

Abstract: A cutting insert for grooving operations includes an elongated clamping portion and a cutting portion. The cutting portion has a chip rake surface and a relief surface meeting at a cutting edge. The relief surface has a plurality of recesses extending to the chip rake surface. In a top view of the cutting insert the cutting edge has the form of a serrated curved cutting edge.

Abstract: A cutting tip for a drilling tool includes a cemented carbide cutting base 11, a diamond element 12 supported by the cutting base 11, and a bonding layer formed between the cutting base 11 and the diamond element 12 in order to bond them. The bonding layer 13 includes diffusion layers S1 and S2 in which one or two or more metals selected from a group consisting of Fe, Ni, Co, Ti, Zr, W, V, Nb, Ta, Cr, Mo, and Hf diffuses into at least one of the cemented carbide or the diamond.

Abstract: A cutting tool in which a cutting insert is resiliently retained. The cutting insert includes a locating portion and a cutting portion having a rake surface and a relief surface. The locating portion extends from the cutting portion away from the rake surface.

Abstract: Disclosed is a turning tool for cutting circumferential grooves into a surface of a polishing pad formed of a resin material and utilized for polishing semiconductor devices. The turning tool comprising a cutting part arranged to have a tooth width within a range of 0.005–1.0 mm, a wedge angle within a range of 15–35 degrees, and a front clearance angle within a range of 65–45 degrees. A polishing pad effectively formed by using the turning tool, and an apparatus and a method of producing such a polishing pad by utilizing the turning tool are also disclosed.

Abstract: A cutting tool, in particular for the turning out of drillings, has a clamping piece (10) for fixing the tool in a clamp holder. The clamping piece (10) includes two clamping surfaces (30), which converge on each other in the direction of the one side (32) of the clamping piece (10). In the direction of the other side (34) of the clamping piece (10), the clamping surfaces extend into a roof-type surface (36). On the side of the clamping piece (10) facing away from the clamp holder, the clamping surfaces connect to a rod-like neck piece (12), which tapers in cross-section relative to the clamping piece (10). The free end of the clamping piece is connected to a cutting piece (14) as one piece, and is provided with a cutting edge (16) on the external end thereof to which a face (18) of the cutting piece (14) connects in the direction of the neck piece (12). A high degree of reinforcement for the neck piece and the cutting piece arranged on its free end with its blade or the blade edge is achieved.

Abstract: A grooving insert has a forward main cutting edge and two opposing side cutting edges extending rearwardly from the main cutting edge on opposing sides of a center line of the grooving insert. Each side cutting edge has a serrated form in a top view of the grooving insert.

Abstract: Disclosed is a turning tool for cutting circumferential grooves into a surface of a polishing pad formed of a resin material and utilized for polishing semiconductor devices. The turning tool comprising a cutting part arranged to have a tooth width within a range of 0.005–1.0 mm, a wedge angle within a range of 15–35 degrees, and a front clearance angle within a range of 65–45 degrees. A polishing pad effectively formed by using the turning tool, and an apparatus and a method of producing such a polishing pad by utilizing the turning tool are also disclosed.

Abstract: Small size insert and insert-blank apparatus for machine tools for grooving and turning have a body with generally parallel and opposing sides, and top and bottom surfaces which have at least a portion thereof inclined from adjacent a first end to the opposite end, and two heads extending from opposite ends of the body, each head having a rear end with which the body forms portions adapted to serve as stops to prevent rearward movement with respect to the machine tool when use. The body of the apparatus is adapted to be mounted in a toolholder having a nest or pocket having an inclined bottom wall which cooperates with the inclined portion of the bottom surface of the apparatus, and a clamp secured to the toolholder having a finger portion cooperative with the inclined portion of the top surface of the apparatus to resist forces on the apparatus during turning.

Abstract: A grooving insert has a forward main cutting edge and two opposing side cutting edges extending rearwardly from the main cutting edge on opposing sides of a center line of the grooving insert. Each side cutting edge has a serrated form in a top view of the grooving insert.

Abstract: A toolholder for a small-size insert having a shoulder for use with a machine tool for grooving, boring and turning has a substantially planar surface portion in an end portion which defines at least one insert-receiving recess extending inwardly into the body of the toolholder, and the end portion defining at least one abutment surface against which the shoulder of the insert may abut to readily orient and rapidly and readily secure the insert in the toolholder.

Abstract: A cutting tool is provided which comprises an end cutting edge at an end of a rake face, and a depression formed in the rake face so as to provide the end cutting edge with a concave edge portion.

Abstract: Tool holder for cutting bodies (5), which may be mounted on a base holder (15) by means of a fixing device (41), and a stop, cooperating with the above, running in a planar embodiment in the direction of the tool holder. A positive positional fixing against any movement along the three axes of the spatial coordinate system may be obtained, whereby the planar embodied stop is divided into planar sections (19, 21), by means of a machined recess (23), between which the recess (23) forms a seat for housing a projecting matching body (25) on the base holder (15) and the walls of the recess (23) form support surfaces (31, 33) for the matching body (25) which each define differing planes, embodied in a planar manner perpendicular to the stop, such as to feed the displacement and torsional forces resulting from the cutting force into the matching body (25) of the base holder (15).

Abstract: Small size insert and insert-blank apparatus for machine tools for grooving and turning have a body with generally parallel and opposing sides, and top and bottom surfaces which have at least a portion thereof inclined from adjacent a first end to the opposite end. The body of the apparatus is adapted to be mounted in a toolholder having a nest or pocket having an inclined bottom wall which cooperates with the inclined portion of the bottom surface of the apparatus, and a clamp secured to the toolholder having a finger portion cooperative with the inclined portion of the top surface of the apparatus to resist forces on the apparatus during turning. Small size insert and insert-blank apparatus optionally have at least one head having a rear end and a body extending from the rear end of the head having top and bottom surfaces with inclined portions intersecting the rear end of the head forming portions adapted to serve as stops to prevent rearward movement with respect to the machine tool when in use.

Abstract: A holder is designed to receive a cutting insert intended for parting and grooving operations. The insert is clampable in a seat formed between a blade tongue and a clamping finger which respectively extend from lower and upper front parts of the holder. A gap separates those front parts in order to enable those parts to be forced towards each other by means of a clamping mechanism mounted in the holder. The clamping mechanism comprises a drawbar, a first end portion of which is movable within a bore formed in one of the front parts, and a second end portion of which is fixed in the other front part. The first end portion of the drawbar includes a head having a frusto-conical abutment surface. A tightening screw is threadedly mounted in the same front part as the head and is arranged to contact the abutment surface to displace the drawbar in a direction forcing the clamping finger and the tongue together to clamp the cutting insert in place.

Abstract: The invention relates to a cutting device comprising a holder (10), which is provided with a jaw-like opening (24) on a clamping head (20) that serves to accommodate a metal-cutting tool (22). The jaw-like opening (24) is located on a longitudinal side (16) of the clamping head (20) and its face (28) extending transversal to said longitudinal side (16) faces a workpiece (30) that rotates during metal-cutting machining. The face (28) is provided, at least in the area in which it leads into the opening (24), with a camber (32) whose curvature corresponds to the curvature of the workpiece (30) having the largest diameter.

Abstract: A metal cutting insert having a pair of cutting portions disposed on either side of a shank portion. Each cutting portion includes a forward cutting edge and two side cutting edges. Each side cutting edge forms part of a shelf that includes chip controlling/breaking structure and is defined by the juncture of a cutting surface with an upper boundary of a side face. The chip controlling structure includes a chip deflecting surface located adjacent the side cutting surface that includes a plurality of concave recesses that generate localized stiffening of a chip as it moves along the chip deflecting surface. Chip controlling structure located adjacent the forward cutting edge includes a downwardly sloping surface that forms part of a channel which extends from the forward cutting edge towards a shank portion of the insert. A pair of ridges located on either side of the channel rise upwardly and reach a height that is above the plane of the forward cutting edge.

Abstract: A directly pressed cutting insert for chip removing machining includes a top surface, a bottom support surface, and edge surfaces interconnecting the top and support surfaces. The top surface comprises a chip surface. A cutting corner is formed by the intersection of two of the edge surfaces and includes a first cutting edge. One of the two edge surfaces includes a first clearance surface having a first clearance angle. The first edge surface includes a second clearance surface having a second clearance angle, which is greater than the first clearance angle. Each of the first and second clearance surfaces connects to the same first cutting edge.

Abstract: A double ended metal-cutting insert includes a pair of circular cutting edges disposed at respective end surfaces of the insert. Each end surface includes an upper portion connected to the cutting edge, and a lower portion connected to the upper portion by a concave transition portion. The lower portion is recessed relative to the upper portion in a direction toward the opposite cutting edge. The lower portion is a flat face oriented perpendicular to the bottom surface.

Abstract: The invention relates to a cutting tool, in particular for the turning out of drillings, comprising a clamping piece (10) for fixing the tool in a clamp holder. Said clamping piece (10) comprises two clamping surfaces (30), which converge on each other in the direction of the one side (32) of the clamping piece (10) and in the direction of the other side (34) of the clamping piece (10) run into a roof-type surface (36) and, on the side of the clamping piece (10) facing away from the clamp holder, connect to a rod-like neck piece (12), which tapers in cross-section relative to the clamping piece (10) the free end of which is connected to a cutting piece (14) as one piece, provided with a cutting edge (16) on the external end thereof to which a face (18) of the cutting piece (14) connects in the direction of the neck piece (12).

Abstract: A parting tool includes a thin holder forming a groove open at one end, and a double-ended cutting insert mounted in the groove. The insert includes front and rear cutting edges and a rear end surface abutting against a rear support surface of the groove. The rear support surface is configured to enable differently shaped double-ended inserts to be mounted therein without the occurrence of contact between the rear cutting edge and a surface of the holder.

Abstract: Small size insert and insert-blank apparatus for machine tools for grooving and turning have a body with generally parallel and opposite sides, and top and bottom surfaces which have at least a portion thereof inclined from adjacent a first end to the opposite end. The body of the apparatus is adapted to be mounted in a toolholder having a nest or pocket having an inclined bottom wall which cooperates with the inclined portion of the bottom surface of the apparatus, and a clamp secured to the toolholder having a finger portion cooperative with the inclined portion of the top surface of the apparatus to resist forces on the apparatus during turning.

Abstract: The tip having a basic form of parallelogram that is detachably mounted by a clamp screw 4 on a tip mounting face 2a of a holder 2, characterized in that two or more concave grooves 6 are formed like parallel stripes on the tip mounting face 2a of the holder 2, and two or more convex lines 7 are formed on its own abdominal face to be fitted in the concave grooves 6, in which the insert is clamped by the clamp screw 4 in a state where its own convex lines 7 are fitted in the concave grooves 6 on the tip mounting face 2a.

Abstract: A metal cutting insert having a pair of cutting portions disposed on either side of a shank portion which also includes a clamping structure engageable by a tool holder by which the metal cutting insert is held in an operative position. Each cutting portion includes a circular cutting edge that is defined by the juncture of a circular clearance surface and a frusto-conical, positive rake surface. The cutting edge is located in a common horizontal plane. A plurality of elongate spaced apart, radially directed recesses are symmetrically spaced with respect to the cutting edge and include outer ends that merge with the frusto-conical rake surface and inner ends which merge with a plateau-like surface having an upper surface located at a level higher than the cutting edge. The plateau-like surface defines a discontinuous circular edge in the form of arcuate ridges.

Abstract: A cutting insert includes a generally polygonal body having minor flank faces, major flank faces, chip breaking faces, major cutting edges formed at the intersection of the first faces and the major flank faces, and minor cutting edges formed at the intersection of the first faces and the minor flank faces. The major cutting edges are generally orthogonal to each other such that each major cutting edge can be alternately exposed for use. In one embodiment, both the major and minor cutting edges are generally linear. In another embodiment, the major cutting edges are generally curvilinear and the minor cutting edges are generally linear.

Abstract: The present invention relates to a tool for chip removing machining, which comprises a holder (1); as well as a tool head (13) connected therewith, which carries at least one cutting insert (18) for chip removing machining, the holder (1) and the tool head being connected to each other by means of serrated surfaces (10, 2), and that the tool comprises members (12, 15, 16) for connecting the tool head (13) with the holder (1). The invention also relates to a tool head (13) and a holder (1) separately. What characterizes the tool according to the present invention is that the dividing plane (4), which is formed by the serrated surface (10) of the holder (1) and the serrated surface (2) of the tool head (13), forms an angle of 45° to a second basal plane (Bp2) of the tool.

Abstract: A turning assembly for turning a workpiece includes a holder and plurality of turning bits mounted next to one another in a parallel relationship for simultaneously engaging a the workpiece. The turning bits are mounted in respective holding elements which are individually adjustably mounted in the holder. Spacers can be provided to space the turning bits apart. Safety devices are provided, each including an elastic element for frictionally retaining a respective turning bit and/or spacer within the holder to enable the holder to be manipulated without the turning bits and/or spacers falling out.

Abstract: A metal cutting insert having a pair of cutting portions disposed on either side of a shank portion. Structure is formed on the metal cutting insert by which the insert is clamped to a tool holder which positions one of the cutting portions in a machining position. Each cutting portion includes a forward cutting edge and two side cutting edges. Each side cutting edge forms part of a shelf that includes chip controlling/breaking structure. Each side cutting edge is defined by the juncture of a cutting surface with an upper boundary of a side face and the chip controlling structure includes a chip deflecting surface located adjacent the side cutting surface that includes a plurality of concave recesses that generate localized stiffening of a chip as it moves along the chip deflecting surface. The forward cutting edge performs cutting operations on a rotating workpiece in a radial direction.

Abstract: A metal cutting tool having an indexable cutting insert retained in an insert pocket of an insert holder. The cutting insert has two opposing side surfaces with a peripheral edge surface extending therebetween and a plurality of cutting portions. The peripheral edge surface has a plurality of abutment sections, each abutment section lying on a portion of a sidewall of an imaginary regular polygon. A plurality of cutting portions extend outwardly from the imaginary polygon and are equal in number to the number of side walls thereof. Each abutment section is located between two cutting portions. The insert holder has an insert pocket in which the cutting insert is retained with the peripheral edge surface being abutted at two abutment sections by two support walls of the insert pocket, the support walls being fixed and integral parts of the insert holder.

Abstract: A metal cutting tool includes a stationary tool holder and a mounting body therefor. The tool holder includes a first coupling part which is restrained by a second coupling part on the mounting body. The coupling parts are coaxially arranged one inside of the other. The coupling pars are conical as viewed in a longitudinal section plane containing the axis. The first coupling part includes teeth projecting generally radially with respect to the axis and received in respective radially-open recesses formed in the second coupling part. Each of the teeth makes contact with a wall of the respective recess at first and second contact places which are respectively situated on opposite sides of a generally radial line of symmetry of the tooth. The contact places are operable to transmit a restraining force from the second coupling part to the second coupling in respective directions. A restraining angle in the range of −5° to +45° is formed at each contact place.

Abstract: A tool includes a holder body having a pocket which has a bottom surface and at least one upstanding support surface. A cutting insert is provided in the pocket, the cutting insert having a side surface structure. The support surface is provided with a cavity which contains a rounded member (e.g., a cylindrical pin). The rounded member is stationarily mounted in the cavity, and a portion of a convexly rounded outer surface of the rounded member protrudes past the cavity and into the pocket. A securing element is attached to the holder to force a side surface of the insert against the convexly rounded surface.

Abstract: A tool for chip removing machining includes a holder and a cutting insert removably mounted therein. The insert includes a shaft having opposite ends and defining a first longitudinal center line. A cutting head projects integrally from at least one end of the shaft. The cutting head includes a cutting edge forming an angle of 45° with the first longitudinal center line. Alternatively, or additionally, the cutting head defines a second longitudinal center line forming an angle of 45° with the first longitudinal center line.

Abstract: The invention pertains to a metal-cutting tool with at least one recess (2) for receiving a cutting insert (3). The cutting insert (3) is securely clamped in the recess (2) by an elastic clamping arm (8), which forms the upper contact surface (14) of the recess (2). According to the invention, the lower contact surface (4) of the cutting insert (3) and the lower contact surface (9) of the recess (2) are at least partially configured in an arc. The radius (r) of the arc of the contact surface (9) is designed slightly smaller than the arc (R) of the contact surface (4). The upper contact surface (5) of the cutting insert (3) and the contact surface (14) of the clamping arm (8) are matched in such a way that mutual contact takes place in a range which is at a distance from the symmetry line (S) in the direction of the cutting edge (11) of the cutting insert (3).

Abstract: A cutting tool has a cutting insert resiliently clamped in an insert pocket. The cutting insert has an abutment surface in the form of a circular segment protruding from a bottom face. The insert pocket has a base jaw with an abutment surface in the form of a circular arc in which the circular segment is received. As a consequence, the cutting insert cannot be removed by sliding it forwardly in the insert pocket.

Abstract: A cutting insert includes a generally polygonal body having minor flank faces, major flank faces, chip breaking faces, major cutting edges formed at the intersection of the first faces and the major flank faces, and minor cutting edges formed at the intersection of the first faces and the minor flank faces. The major cutting edges are generally orthogonal to each other such that each major cutting edge can be alternately exposed for use. In one embodiment, both the major and minor cutting edges are generally linear. In another embodiment, the major cutting edges are generally curvilinear and the minor cutting edges are generally linear.

Abstract: A holder is designed to receive a cutting insert intended for parting and grooving operations. The insert is clampable in a seat formed between a blade tongue and a clamping finger which respectively extend from lower and upper front parts of the holder. A gap separates those front parts in order to enable those parts to be forced towards each other by means of a clamping mechanism mounted in the holder. The clamping mechanism comprises a drawbar, a first end portion of which is movable within a bore formed in one of the front parts, and a second end portion of which is fixed in the other front part. The first end portion of the drawbar includes a head having a frusto-conical abutment surface. A tightening screw is threadedly mounted in the same front part as the head and is arranged to contact the abutment surface to displace the drawbar in a direction forcing the clamping finger and the tongue together to clamp the cutting insert in place.

Abstract: A clamping arrangement includes a holder blade having a body portion, the body portion having a key slot and a key recess are disposed relative to each other and relative to an insert-receiving slot such that, when a first keying member of a key is received in the key slot and the second keying member of the key is received in the key recess and the key is moved from an at-rest position to an opening position, the height of the insert-receiving slot is increased against resilient forces of the body portion to a sufficient height to install an insert for the holder blade and, when the key is returned to the at-rest position, the resilient forces cause the height of the insert-receiving slot to decrease and clamp the insert between the upper and lower surface of the insert-receiving slot.

Abstract: A cutting insert for grooving operations includes a central shank portion and a forward cutting head. The cutting head includes a front clearance surface having a main cutting edge at an upper end thereof. The clearance surface is non-planar. Rather, the clearance surface exhibits a curvature in order to strengthen the main cutting edge.

Abstract: A cutting tool is provided which comprises an end cutting edge at an end of a rake face, and a depression formed in the rake face so as to provide the end cutting edge with a concave edge portion.

Abstract: A punch for producing decorative cutouts includes a base with a die secured thereto, a cutter mounted above the die and urgeable downward therethrough by a lever pivotally secured to the base, at least one spring compressed between the base and an under face of the cutter, and an ejector mounted in an upper face of the die. The cutter includes an inner leading edge, an outer trailing edge, an inclined periphery extending between the inner and outer edges, and at least one central cutting edge. The die has an outer profile configured to mate with the edges of the cutter, and at least one inner profile configured to mate with the central cutting edge. An ejector is mounted in a recess surrounding the outer profile of the die, whereby cutouts are ejected efficiently from the punch.

Abstract: A double-ended parting or grooving insert comprising a central body portion and a pair of opposite cutting end portions; each cutting end portion having an upper rake surface and front and side relief flanks and a front cutting edge formed at an intersection of the rake surface and the front relief flank; the front relief flank comprising an upper relief flank surface; a lower abutment surface inset with respect to the upper and disposed substantially normally with respect to a longitudinal median plane intersecting the front cutting edges and an intermediate surface serving to bridge the upper and lower surfaces.

Abstract: A cutting tool has a cutting insert resiliently clamped in an insert pocket. The cutting insert has an abutment surface in the form of a circular segment protruding from a bottom face. The insert pocket has a base jaw with an abutment surface in the form of a circular arc in which the circular segment is received. As a consequence, the cutting insert cannot be removed by sliding it forwardly in the insert pocket.

Abstract: The present invention relates to an indexable cutting insert (10) for the turning of grooves with triangular basic shapes where each insert comer features a projection (16). Each projection supports a transverse cutting edge (17) and connecting diverging cutting edges (18, 19), so that the projection (16) seen in a view directly from above has a symmetrical shape. The one outer side edge (18) of the projection (16) is bordered by an unbroken flat flank surface (22) whilst the connecting flank surface on the other side edge (19) is comprised of two partial surfaces (27, 28) of which the one nearest the edge (19) partial surface (27) has a smaller clearance angle than the partial surface (28) nearest the bottom.

Abstract: The present invention relates to a turning insert that comprises a generally rectangularly shaped body having a front end surface with a main cutting edge at the intersection between the front end surface and an upper land area. A chipforming area is provided in the forward portion of the upper surface and is shaped in the form of a number of distinctly provided recesses and ridges in order to promote improved chip control and to obtain narrower chips in grooving operations.