Abstract: A machine tool extension for interfacing a cutting tool having a generally cylindrical shank portion to a tool holder having a central opening. The extension comprises an elongate, generally cylindrical shank member having first end and a reduced diameter second end. The first end of the shank member is insertable into and securable within the central opening of the tool holder. The extension further comprises a bushing member having an aperture extending longitudinally therethrough. The second end of the shank member is insertable and securable within one end of the aperture, with the shank portion of the cutting tool being at least partially insertable into and securable within the other end of the aperture. The shank member is formed to have an outer diameter which slightly exceeds the diameter of the central opening of the tool holder.

Abstract: A reamer for material-removing finishing machining of drilled surfaces in workpieces made of metal. The reamer has a blade insert and two guide bars associated with the blade insert. The first guide bar trails the blade insert, as seen in the direction of rotation of the reamer, by approximately 40.degree. and the second guide bar is arranged opposite the blade insert. The reamer has at least one additional blade insert that leads the second guide bar by approximately 40.degree..

Abstract: A single point drill particularly adapted to producing small diameter deep holes utilizing a peck feed cycle routine. The preferred embodiment features a limited flute length with a depth approximately 1/3 the drill diameter and a dual point edge consisting of a shallow cutting angle and a steep relief angle. A negative rake angle runs along this edge functioning as a knife edge that will cut on opposite rotation, countering the unbalanced forces inherent in a single point tool. A sharpening fixture consisting of 2 parallel slates secured with a T-headed bolt and an anti-rotation pin. The lower plate features a central groove to locate the drill, the upper plate having a short land that facilitates orienting and clamping the drill flute. The forward end of the fixture mimics the drill point allowing the drill to be sharpened on a grinder table or by hand with a suitable abrasive stone or file.

Abstract: An auger bit for forming bores having a circular cross section in a workpiece is disclosed. The bit has an elongate auger portion, a shank, a lead screw, a chisel blade, a spur blade, and a shearing blade. The elongate auger portion has an elongate shaft with a elongate helical land formed therein defining a flute between adjacent turns on the elongate helical land. The helical land has a lead edge and following portion. The shank is integrally connected to one end of the elongate auger portion and is adapted to engage a drill. The lead screw is integrally connected to the other end of the elongate auger portion and is for engaging the workpiece. The chisel blade extends outwardly from the leading edge of the elongate helical land and is for chipping material from the workpiece. The spur blade extends longitudinally from the elongate helical land in the direction of the lead screw. A cutting edge extends longitudinally from the following portion of the elongate helical land proximate to the leading edge.

Abstract: A debur tool for simultaneously removing burrs from holes in a workpiece, such as those in a header box tube sheet, also has a beveled surface adjacent a cutting edge for chamfering an edge of the hole from which a burr is removed. The cutting edge is horizontally offset from a shaft carrying the cutting edge.

Abstract: A cutting tool such as a drill or reamer for machining a bore in a workpiece is provided with at least one chamfered cutting edge on its distal end having an enlarged radial extent. The chamfered edge is defined between a tapered leading end, and an undercut end, and has a radial extent about 2.5% greater than the radial extent of the shaft of the tool. At least 40% of the length of the chamfered edge is substantially parallel to the axis of rotation of the tool shaft. The tapered and radially enlarged geometry of the chamfered cutting edge advantageously allows the drill or reamer to machine a bore in a workpiece formed from materials having significant spring-back characteristics, such as aluminum, titanium, or nickel alloys without sticking or galling during the machining operation, thereby greatly increasing tool life.

Abstract: The invention is directed at a drill tool assembly including a holder having a shank and head portion and having a axial centerline or rotational axis on which said holder is rotated in use. The head portion includes a holder slot at least over a central portion of the head, with the slot being oriented perpendicularly to the axial centerline of the holder. The holder slot also includes a locating boss extending upwardly from the bottom of the slot, which includes first and second surfaces, with at least one of the surfaces being located in a predetermined position with respect to the axial centerline of the holder, and substantially parallel to this centerline. A drill insert having first and second cutting surfaces is selectively positioned within the holder slot, and includes a locating slot adapted to be positioned in a predetermined orientation relative to the boss provided in the holder slot.

Abstract: A countersink reamer for three dimensional interior/exterior small bores, being comprised mainly of a plurality of O rings, piano wires and an electric or pneumatic hand tool with a claw and rotatable to provide moving power; the piano wires are arranged in a bundle, the front end thereof are welded and fixed, and their rear end are welded to a cylindrical seat, those of the piano wires not welded are fitted over with several O rings, the bundle of piano wires connected to the cylindrical seat is inserted to be mounted on the claw of the electric or pneumatic hand tool; so that rough edges resulted on both the interior and the exterior bore rims of a small rough bore on a normal workpiece can be synchronically abraded and countersink-reamed by swivelling grinding and cutting action of the piano wires which are rotating after having been inserted into the bore with the O rings abutting against the wall of the bore and been activated for rotation.

Abstract: A chip removal tool for finishing the radial surface of a bore and having a cylindrical bit for mounting a cutting element and a deflector positioned adjacent the cutting element to deflect chips cut from the bore and urging the chips into a flow of fluid from respective cooling and lubricating sources.

Abstract: A drilling tool includes a drill body having axially spaced front and rear ends. The front end includes tangential pockets for carrying cutting inserts spaced by respective radial distances from a center axis of rotation of the drill body. Two chip canals are formed in the front end surface adjacent respective pockets for conducting away chips. The canals are interconnected by a chip space located rearwardly of the front surface, to form in the drill body a bridge which extends diametrically and carries a plurality of the pockets. Each insert pocket includes an axially extending abutment surface against which a rear wall of a respective insert engages. Each of the abutment surfaces and rear walls is of semi-circular shape.

Abstract: A plastic pipe end forming tool to form both inside and outside bevels on a pipe end. An elongated body has a cavity constituting a cylindrical channel. A pair of opposed protrusions extend into the cylindrical channel to form a V-shaped space to receive the pipe end therein and to allow rotation of the pipe in the cylindrical channel and thereby form bevels on the pipe end.

Abstract: A boring bar includes an insert pocket formed on the back side of a relief in the working end of the bar, for the removable installation of a cutting insert therein. The insert pocket may be formed to provide a positive rake angle for the insert installed therein, relative to the axis of the bar, and further may include a positive angle relative to the radius of the bar as well. The force imparted to the insert as the bar is forced against the workpiece, tends to force the insert upwardly and inwardly into the pocket of the bar, thus assisting in holding and securing the insert to the bar. The bar is also thicker at the upper portion of the insert pocket than at the lower portion of the pocket, thus providing additional strength and stiffness to the bar in this critical area to reduce the possibility of chatter and breakage of the bar. Either the tool moves and the workpiece is stationary, or the workpiece moves and the tool is stationary.

Abstract: A deburring tool for deburring the edges of boreholes. The tool has a base body in which at least one recess aligned across the longitudinal axis of the base body is provided, where at least one blade is arranged in said recess so it can be displaced under spring load in the longitudinal direction of the recess. A compression spring is provided in the longitudinal bore of the base body and comes in contact with one end of a control pin whose other end engages in a control recess in the blade to provide at least a holding power to the blade in the direction of displacement.

Abstract: A reamer for precision machining of holes includes a reamer body and a knife plate supported above the exterior of the body and extending along the exterior. The knife plate has a front lower radial height cutting region and a rear taller radial height cutting region joined by an inclined step so that the first front region does the major cutting and the second rearward region does the finer machining. The front cutting region has an entrance bevel. The inclined flank shapes of the cutting regions are disclosed. Reamer guide strips supported along the support have a similarly shaped bevel and step as the knife plate.

Abstract: A deburring tool having an insert having four cutting edges such that the tool will cut in either direction of rotation is disclosed. The insert is pivotably mounted on a handle.

Abstract: An external reamer has a cutting head (11) having two claws (15, 16) projecting parallel to the axis from a base (12). On one claw (15) is fastened a cutter plate (28), whose axially parallel cutting edge (32) is directed radially inwards in order accordingly to machine a cylindrical outer side of a workpiece. On the other claw(16) a guide strip (45) is detachably fastened by means of at east one clamp screw (57), so that its guide surface (48) lies, diametrically opposite the cutting edge, against the outer side of the workpiece and stabilizes the machining operation. This guide strip (45) is preferably capable of fine adjustment in the radial direction by means of a pressure screw (63). The detachability of the guidestrip (45) has the advantage that the surface of the guide face (48) can be produced without problems separately from the cutting head (11) and with any desired shape. In the same way a plurality of similar guide strips distributed around the circumference may also be provided.

Abstract: Reamers, when operated with large amounts of material removed and at high reaming speeds, encounter difficulties when they ream in material in which permanent structural changes occur on the application of heat and subsequent rapid cooling. These difficulties are avoided in that the transition region between the main cutting edge and the minor cutting edge follows a constantly curved path at least one end region of which runs tangentially to at least the minor cutting edge.

Abstract: A drill comprising a holding section, a prismal section receivable by the holding section, and a top-truncated, pyramidal section which is integral with the prismal section, with the prismal section having side faces and side ridges defined by the adjoining two side faces, the top-truncated, pyramidal section having end faces which taper and coverage on the axis of rotation of the drill, end ridges which are defined by meeting of the adjoining two end faces, and a truncated surface extending across the axis of rotation and forming an angle of more than 1.degree. to less than 90.degree. with the cross-section of the prismal section. The end faces and end ridges of the pyramidal section extend from said side faces and side ridges of the prismal section, respectively. Because the apex of the drill is located out of the axis of rotation, it has enhanced cutting performance.

Abstract: A boring bit includes a shank adapted to be mounted on a rotary tool. A blade is mounted on the shank and is resiliently deformable to reduce its boring diameter.

Abstract: A hand operated countersink has a shaft attached at one end to a cutting insert and at the other end to a handle, wherein said cutting insert is substantially of isosceles triangular shape. The insert has at least two cutting edges each disposed along an equal side of the triangle, one of the cutting edges being operative to cut when the shaft is rotated in one direction, and the other cutting edge being operative to cut when the shaft is rotated in the other direction. In a preferred embodiment, the insert has four cutting edges, two disposed along opposite edges of one equal side of the triangle, and two disposed along opposite edges of the other equal side of the triangle.

Abstract: A single-blade reamer is guided in a hole by means of at least one guide fillet. The guide fillet is provided with a coating of cubical boron nitride (CBN) in the region of its guide surface facing the wall of the hole. The guide fillet thus withstands heavier loads, so that the reamer is suitable in particular for the economical machining of hardened steel alloys.

Abstract: A manually operated device including a tool holder used as a handgrip and a tool with a material-processing tip. The tool has a shaft having an elbow with respect to the tool holder and being rotatably positioned in the tool holder. The material-processing tip is positioned on a first axis of the shaft, and a second axis of the shaft is rotatably maintained in the handgrip, so that a working pressure exerted on the handgrip is applied offset by a distance between the two axes. Material processing, for example deburring or countersinking, is possible without having to regrip the handgrip.

Abstract: A rotary or rotary/percussion drill bit 10 has a taper socket 14 in one end. A wall 18 bounds the socket 14. A plurality of recesses 20 is provided in the wall. In one embodiment, each recess 20 extends longitudially and resembles a flute. It has a valley 22 flanked by peaks 24. In another embodiment, the recesses may be circumferential, e.g. helical.

Abstract: A multi-purpose arrow shaft assembly tool is provided having several implements capable of being received within a handle. One of the implements is an insert arbor over which point inserts and nock inserts may be placed which the inserts are heated and inserted into the hollow arrow shaft. To aid in preparing the shaft for receipt of the inserts, a facing cutter and a burring tool are also provided. The facing cutter has an arbor which guides the cutting blade of the facing cutter to produce a perpendicular cut relative to the longitudinal axis of the arrow shaft. The burr is housed within the handle so that the interior of the handel serves as a guide when deburring the arrow shaft. A nock adjusting implement is also provided which not only aids in the rotation of a friction fit nock within the nock insert, but also serves to record and transfer the relationship between the groove in the nock and one of the veins so that indexing of one arrow may be transferred to other arrows.

Abstract: A reamer tip including a main cutting edge and a auxiliary cutting edge adjoining the first main cutting edge; and a flank provided in a region of the main and auxiliary cutting edges and including a first inclined flank region having a first back angle of about 7.degree., and a second inclined flank region directly adjoining the auxiliary cutting edge, extending from the auxiliary cutting edge to the first flank region, and having a second back angle substantially smaller than the first back angle.

Abstract: A cutting plate for a reamer for fine machining of metal workpieces including a main cutting edge, an auxiliary cutting edge, an apex point at which the auxiliary cutting edge is connected with the main cutting edge, and a chip deflecting surface limited by a chip deflecting step having a high point located opposite a region of the apex point, a first region associated with the main cutting edge and descending, starting from the high point, away from the main cutting edge, and a second region associated with the auxiliary cutting edge and extending relative to the auxiliary cutting edge at an angle of from 0.degree. to about 10.degree..

Abstract: A platform for supporting an engraving head in a manner accommodating translational movement without any associated rotation. The platform has a deck which is supported by a pair of flexible support columns. In operation the platform is situated alongside a rotating printing cylinder. The engraving head is mounted on the deck of the platform and is provided with a guide shoe which rides against the surface of the printing cylinder. As the cylinder rotates to angular positions having different radii, the engraving head responds with a purely linear reaction. Consequently the engraving head is able to engrave uniform-depth cavities in the surface of the printing cylinder. In two alternative embodiments the deck is driven by a resilient link arrangement which is coupled to a leadscrew and carriage assembly.

Abstract: A cutting edge 18 is provided on the end of a cutter tip 12 on a gun drill body 1. The cutting edge 18 has: a radially inner region providing a convex curved cutting edge portion 23, a radially outer region providing a straight cutting edge portion 19 and an intermediate region which provides a concave cutting edge portion 22 having a tapered portion 20 and a concave portion 21. The convex curved cutting edge portion 23, when viewed in the direction of the axis O, presents an arc shape, the radius R of the curvature of which is determined in relation to the outside diameter D of the gun drill so as to range from 0.1.times.D to 0.4.times.D. Thus, a gun drill is provided which exhibits an enhanced severing effect to cut metal chips into pieces so as to prevent clogging, as well as to prevent an increase in the cutting resistance, thus meeting the demand for a greater feed rate.

Abstract: Drill bit of the twist drill type with turns which are held together by a drill center web and each issue in a radially extending cutting edge of which one extends to the bit axis and the other is shorter than it. This is characterized by the following features:a) the cutting edges (2,3) formed by continuos straight edges lie essentially in a plane coinciding with the bit axis (9),b) the cutting edges (2,3) form an obtuse angle (cutting angle), lying below 180.degree., of at least 175.degree.,c) the cutting edges (2,3;16) having a leading edge angle (K) of about 30.degree. with a rake angle (S.sub.1, S.sub.15) of about 30.degree. to 45.degree.,d) the diameter (D) of the drill center web (6) is at most half the bit diameter.

Abstract: A tool for processing holes has a shaft which can be clamped in a drive element for executing a forward stroke into a working position within a hole, a return stroke, and an at least rotating working motion of the tool, two support elements arranged on the shaft, wires clamped at one end of the shaft between the support elements and being sprung bowing away from the shaft in an arc shape, the wires being coated with a cutting medium. One of the support elements is axially adjustable relative to the shaft. The shaft has axially positioned slots distributed on a circumference in two regions axially offset from one another. The shaft also has an axial hole leading out from both ends of the shaft and extending into the regions. The support elements are formed as limit stops inserted in the axial hole and each end just short of an entry of the hole into an area of the slots. The wires have ends extending through the slots and coming to rest on the limit stops.

Abstract: A boring bar tool for use with a tip is disclosed which has a tool body. The tip is mounted to one side of a forward end of the nose of the tool body. A neck is formed at a proximal end of the nose, and a shank in the form of a shaft is formed at a proximal end of the neck. The neck has a cross-sectional area in a plane perpendicular to an axis of the shank which is larger than the cross-sectional area of the shank in the plane.

Abstract: A reamer includes a shank portion and a reamer head fixed to the shank portion. A cutting blade is mounted on the reamer head to project axially forwardly from the front end of the reamer head. A bearing guide pad is mounted on the reamer head circumferentially spaced from the cutting blade downstream with respect to the rotating direction of the reamer, and a sizing guide pad is mounted on the reamer head substantially diametrically opposed to the cutting blade. The axial lengths (L2) of the guide surfaces of the bearing guide pad and the sizing guide pad are both not larger than the axial length (L1) of the circle land of the cutting blade, the axial length (L1) of the cutting blade is not larger than the diameter (D) of the reamer, and the width (W2) of the sizing guide pad is not larger than the width (W1) of the bearing guide pad. The axial lengths (L2) of the guide surfaces of the guide pads are preferably 5 mm to 15 mm where the diameter of the reamer is 5 mm to 100 mm.

Abstract: A reamer having a single cutting blade with parallel clamping and seating surfaces seated in an anvil having converging radially outward extending planar surfaces for enhancing the clamping effectiveness of an installed anvil/cutting blade adjustably positioned radially by a pair of set screws angled to provide fine adjustment.

Abstract: A deburring tool is constructed of a pair of wire sections resiliently interconnected with each other so that each biases the other against the internal side walls of a bore formed in a workpiece. Abrasive material is provided on either or both of the sections, and rotation of the tool about its longitudinal axis causes engagement of the abrasive material with the area of the bore wall at which burrs are to be removed. The tool can be formed of a single length of wire having a curved portion on which the abrasive material is located, or the tool can assume various other configurations. The single wire version can be used to remove burrs from the interior of very small bores.

Abstract: A boring bar tool for use with a tip is disclosed which has a tool body. The tip is mounted to one side of a forward end of the nose of the tool body. A neck is formed at a proximal end of the nose, and a shank in the form of a shaft is formed at a proximnal end of the neck. The neck has a cross-sectional area in a plane perpendicular to an axis of the shank which is larger than the cross-sectional area of the shank in the plane.

Abstract: A cutting tool consists of a cutting body extending from a front end to a rear end and defined by at least an exterior surface. A shank is connected to the cutting body at the rear end. The cutting body is provided with a slightly concave base surface positioned at the front end. A pilot unit extends outwardly from the base surface and is defined by at least an outside surface thereof. First and second surfaces extend inwardly from the exterior surface of the cutting body and intersect each other to form a flute. The first surface, second surface and the flute extend into the pilot unit. A cutting edge of the cutting tool is formed at the intersection of the first surface with the base surface of the cutting body.

Abstract: A reamer with at least one cutter plate that is held by at least one clamping jaw located in a recess in the head of the reamer and having an opening for a clamping screw is proposed, said reamer being distinguished by the fact that the clamping jaw (5) is shaped essentially as a triangle when viewed from the top, that the opening (23) for the clamping screw (7) is located in a corner of the triangle, and that the lateral surfaces of the clamping jaw (5) starting from this corner form guide surfaces (13, 15), which are provided with contact surfaces in the recess (9) in the head of the reamer. By using this clamping jaw, the cutter plate can be optimally clamped and aligned without weakening the main body of the reamer. Both the flank and lateral surfaces of the clamping jaw interact with the stop surfaces in a recess (9) in such a manner that optimal diversion of the clamping forces in the main body of the reamer also takes place.

Abstract: A single-blade reamer (30) is disclosed with a cutter plate having a cutter blade (5) and attached to the base body (20), and with two guide strips (6, 7) disposed at the circumference of the base body. A chip-guide device (8, 9, 10, 11) is disposed between the cutter plate or, respectively, the cutter blade (5), and the first guide strip (6) following at an angular distance relative to the cutter (5) as seen from a point of a fixed external coordinate system when the reamer (30) is rotating in a proper cutting direction and/or between the first guide strip (6) and a second guide strip (7), disposed opposite to the cutter blade (5).

Abstract: Disclosed is a spotweld removal tool adapted for removing spotwelds which join two or more layers of sheet metal to thereby free the sheet metal layers from one another. The spotweld removal tool comprises a split point twist drill having a central cutting tip (38) having leading edges (44 and 46) and defined by flared walls (56 and 58), recessed surfaces (64 and 66) adjoining the flared walls and peripheral cutting flats (40 and 42).

Abstract: To permit boring with replaceable cutter elements (10, 10a, 10b), particularly into materials where, upon withdrawal of the boring tool from a bore hole (40), grooves or scratches are to be avoided, two cutter elements are positioned on a fluted cylindrical body (1), the cutter elements being so located that the inner cutter element (10b) is positioned on the body so that an effective cutting edge (19) thereof is radially inwardly of the theoretical circle (33) formed by the outer cutter element (10a) upon rotation of the tool, the cutting corner of each cutter element is formed as a relieved or chamfered corner (15) and forms a chopped corner cutting edge (22).

Abstract: A tube reaming and deburring device (10) for deburring and beveling the edges of a tube end (12). The tube reaming and deburring device (10) comprises an inner edge cutting assembly (18) and an outer edge cutting assembly (20) mounted on opposite ends of a handle member (22). The inner edge cutting assembly (18) includes a first blade support member (24) having a forward portion (25) defining a conical surface (26). The inner edge cutting assembly also includes a plurality of replaceable blade members 30 mounted on the conical surface 26 for engaging the inner edge (14) of the tube end (12). The outer edge cutting assembly (20) includes a further blade support member (42) having a forward portion provided with a forwardly disposed tube receptor (46) defining a conical sidewall (48). The outer edge cutting assembly (20) also includes a plurality of replaceable blade members (50) mounted on the conical sidewall (48) for engaging the outer edge (16) of a tube end.

Abstract: A diamond tipped twist drill for drilling holes in a work piece consists of a body forming a pair of flutes, each flute forming a channel that essentially parallels the flutes. Each channel ends at an aperture formed in the body nearest a cutting end of the drill. Diamond material is pressed into the flutes and through the aperture. Subsequent machining at the cutting end of the drill bit body exposes the sintered diamond forming a finished diamond cutting tip for the twist drill.

Abstract: A cutting tool for forming undercuts in boreholes includes a cutting member pivotally and rotatably supported in a tubular drive shaft. The combination of the drive shaft and cutting tool provide a ball joint so that the cutting tool is pivotally supported relative to the drive shaft axis. The drive shaft has an guidance bore for the cutting tool. Guidance stop faces in the guidance bore transmit rotational movement to a head forming a cutting member on the cutting tool. The head forms the undercut. The head rolls over the surface to be undercut.

Abstract: A cutting tool for a lineal milling machine has a female tapered surface for close tolerance matching to the outer, male tapered surface on the outside of the spindle which mounts the cutting tool to provide the maximum width of support for the cutting edge. The cutting edges comprise a plurality of carbide inserts, each with its own flute formed in the body of the tool, such that as the cutting tool is rotated at high speed an annulus of cutting surface is created which is ideally suited for use with the following method. A new method for lineal machining includes the steps of advancing the cutting tool into the workpiece to form a substantially arcuate edge, retracting the cutting tool from the workpiece, indexing the cutting tool to an overlapping position, and then advancing the cutting tool into the workpiece to remove the amount of overlap, with those steps being repeated to mill pocket openings or for any other lineal milling application.

Abstract: Disclosed is a drill for drilling thin plates and which has a pair of major cutting edges each including an inner major cutting edge diagonally extending in an inner portion of the tip so as to form a protrusive leading part, and an outer major cutting edge radially extending in the tip, a chisel edge formed at the junction of the inner major cutting edges, and continuous flanks formed behind the inner major edges and the outer major cutting edges, respectively. The diameter of the leading part formed by the inner major cutting edges is in the range of 40 to 50% of the drill diameter, the point angle formed between the inner major cutting edges is in the range of 100.degree. to 115.degree., the outer corner angle formed between the outer major cutting edge and a plane perpendicular to the axis of the drill is in the range of 4.degree. to 10.degree., and no margin is formed in the circumference of the tip.

Abstract: An elongated grooving or threading tool has a cutting section and a rearward cemented carbide section which are, respectively, held together in axial alignment by a threaded fastener and a drawbolt which engage the intermediate section and hold the respective connections under compression.

Abstract: A rotary cutting tool including an elongated generally cylindrical holder having a recess into which is fitted a disposable cutting insert. The insert is held in place by a clamping member which bears against a surface of the insert and which is attached to the holder by a clamping screw. Radial adjustment of the insert can be effected by adjusting screws which have camming surfaces which bear against a corresponding camming surface of the insert. In axial cross section, the axis of each adjustment screw is parallel to the axis of the clamping screw and to a horizontal axis of the holder, and an axis of the insert is at an angle relative to a vertical axis of the holder.

Abstract: The cutter head of a reamer carries a circular tool bit and two guide members. Each guide member has an outer-most edge at the furthest distance from the center of rotation of the tool and slanted edges inclined at progressively greater angles from the outer edge towards the front of the tool where the initial cut takes place. The first slanted edge, at an angle of less than 10 degrees and preferably between 3 and 5 degrees, intersects the outer-most edge at a point which lags the extreme point on the tool bit by about 0.4 mm in the direction of advance of the tool. The first slanted edge extends at least to the radial plane containing the extreme point of the tool bit. Thereafter, a slanted edge at an angle inclined between 15 and 25 degrees extends in the forward direction, to be followed by a third slanted edge inclined at an angle to the outer-most edge of between 30 and 75 degrees.

Abstract: The invention relates to a drill for metal drilling, comprising a drill body and a drill tip provided with cutting portions. The drill tip is detachably secured to the drill body by means of fastening devices, which are arranged on opposite sides of the centerline (CL) of the drill. The planar lower face of the drill tip is provided with a central tap which engages in a central recess in the mainly planar front surface of the drill body in order to center the drill tip relative to the drill body. A central fluid passage is formed in the drill body, which transforms into eccentrically arranged fluid passages in the drill tip. The fastening devices form at least partly walls in the eccentrical fluid passages.

Abstract: An insert cutter includes a body having at least one generally radially outwardly-opening recess disposed adjacent a forward end face thereof. A cutter insert is received in the recess. The insert is a polygonal shape having a front face, a rear face and side faces. Each corner portion where adjacent side faces intersect each other is removed to provide first and second corner faces. The insert has main cutting edges each defined by the front face and a respective one of the side faces, auxiliary cutting edges each defined by the front face and a respective one of the first corner faces, and corner cutting edges each defined by the front face and a respective one of the second corner faces. Each side face serves as a flank of a respective one of the main cutting edges with a positive clearance angle A. Each first corner face serves as a flank of a respective one of the auxiliary cutting edges with a positive clearance angle B.