Abstract: A modular surgical drill in the form of a rigid drill shaft and a drill bit which are connected together at the rear end of the drill bit and the forward end of the drill shaft by a tongue-and-groove arrangement. Each of the shaft and drill bit are provided with through bores extending centrally through their entire length. These bores become aligned upon assembly of the drill bit and shaft. The modular drill is intended to be employed with a guidewire for drilling holes into bone. The assembled drill bit and shaft are placed on the guidewire and moved down such guidewire into contact with the bone, whereupon a tunnel may be formed into the bone by rotating and advancing the drill bit along the guidewire. The dimensions of the bore and guidewire are so selected as to prevent the drill bit and drill shaft from moving relative to one another once they are assembled and mounted upon the guidewire.

Abstract: A cutting tool particularly adapted for machining brittle plastics in which the cutting head has its cutting edges in the first and fourth quadrants of the x-y axes and contained in a common plane on opposite sides of the axis of tool rotation. The cutting edges are on two planar inserts, which can be either integral or separate elements, which meet at the common plane and each of which is relieved or cut away in the opposite quadrant from its own cutting edge to expose the cutting edges of the other. The walls defining the reliefs have 2 or more non-aligned sections forming different angles with the axis of rotation with the steepest angle beginning at the axis and preferably inwardly of the tip of the tool and, overall, exposing not less than a full quadrant of the cutting edge of the other insert while providing cavities and contours which control the movement of the chips and the flow of coolant fluids.

Abstract: Adjacent one end thereof the shank of a back spotfacing tool has therein a transverse slot, and a cutter mounting pin which extends between opposite sides of the slot parallel to the shank axis. A cutter has in one end thereof a U-shaped slot which is inserted removably over the pin to support the cutter for limited pivotal movement about the pin into and out of an operative position in which a flat, external, limit surface formed on the side of the cutter remote from the open end of its U-shaped slot engages the bottom of the slot in the shank to support the cutter for a cutting operation, and to prevent removal of the cutter from the pin. The cutter may be swung manually to an inoperative position in which the open end of its slot is positioned to permit removal of the cutter from the pin, or the replacement thereof over the pin.

Abstract: A drill having at least one and generally at least two cutting inserts fixed in a cutting end of the drill and in which each cutting insert is a polygonal body having at least three cutting vertices and respective cutting edges between the vertices which are set back so that cutting points are formed close to a vertex. The partial cutting edges formed by the setback extend rectilinearly to the cutting points and include an angle of up to 170.degree. between them.

Abstract: A medullary reaming system includes a flexible, hollow, tubular shaft formed of a nickel-titanium alloy having one end coupled to a rotary drive and having the other end coupled to a cutting head by means of a male connector on the shaft engageable in a female connector on the head. The female connector is a tubular shank with diametrically opposed slots in the outer surface thereof, while the male connector has flexible arms with latch tabs engageable in the slots to latch the head to the shaft. A support has a plurality of notches for respectively storing cutting heads. The head shank is received in the notch with the notch edges received in the shank slots, so that when the male connector on the shaft is inserted into the shank the notch edges prevent latching of the head to the shaft until the head is removed from the support.

Abstract: A cutting insert having a cutting head and a coupling shank integral at one end thereof with the cutting head and including a screw threaded portion. The cutting insert is formed by a powder metallurgy process of compacting and sintering and the screw threaded portion is constituted by a substantially cylindrical body having a pair of diametrically opposed, longitudinally truncated planar portions interposed between substantially curved cylindrical portions having arcuate surfaces on which there are formed a non-continuous screw thread, the arcuate surfaces extending between 50 to 85% of the total peripheral extent of the cylindrical body of which they form part. There is also disclosed a powder metallurgy process for manufacturing the cutting insert.

Abstract: A reamer tip having a face and a V-shaped indentation formed in the face and having sides, which form with an imaginary plane extending parallel to the face an angle of about 9.degree.-12.degree., preferably about 10.degree..

Abstract: A thread cutting tool which can be configured to cut threads in a variety of bore sizes using universal thread cutting chasers mounted in select radial extension such as by using variable length tool blocks which are themselves interfit within retaining slots in the head portion of the tool, or by providing alternate radial position notches an the head portion for mounting the cutting chasers. By using variable tool blocks mounted to the head portion of the tool, universal thread cutting chasers having a preselected thread pitch can be utilized for multiple bore sizes, thus saving the expense of providing chasers or head portions corresponding to each bore size. Alternately, by providing alternate radial position notches in the head portion for mounting the cutting chasers, a single tool can be used for different bore sizes, such as for undertaking a start thread cut in a bore and then undertaking a finish thread cut in the pre-cut bore using an alternate radial position for the chasers.

Abstract: An adjustable die assembly having a ring structure with a clear central aperture for locating the ring structure along an axial length of a rod to have threads repaired or cut, and having a plurality of thread cutting chaser inserts connected to tool blocks which are slidable radially on said ring, each tool block connected to a threaded adjustment shaft, threaded into said ring for adjusting the radial position of each chaser insert. Alternatively, each threaded adjustment rod can be provided with a pinion gear, and a rim gear can be in mesh with each pinion gear, and a gear device can be provided for turning the rim gear to simultaneously adjust all chasers radially.

Abstract: A high speed rotary boring tool has a plurality of cutter inserts evenly spaced around the circumference of a boring bar. Each cutter insert is individually adjustable so that its cutting tip is spaced a desired distance from the tool rotational axis. Each cutter insert is mounted so that its leading face has a zero rake angle in the axial direction, and a negative rake angle in the radial direction. The cutting tip on each insert is defined by two chamfer surfaces on the intersecting edges of the insert leading face, such that each chamfer surface acts as a chip-deflector surface. The boring tool is designed for cutting action during axial feed into the hole and also during axial feed out of the hole.

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 Drilling tool for metallic materials comprises a holder (1) having an axial clamping slot in which a plate-shaped drilling blade (2) is inserted and clamped against a limb (8) of the clamping slot by means of a threaded pin (3), which is provided with a head (21) and which engages in a bore (15) in the drilling blade (2) and in a bore (12) in said limb (8). The center axis (13) of the limb bore (12) is offset relative to the center axis (24) of the drilling blade bore (15). The mutually facing circumferential edges of the head (21) of the threaded pin and the bore (15) of the drilling blade is bevelled. A centering pin (11) is inserted in the holder (1) and engages in a centering slot (18) in that side (17) of the drilling blade (2), which is contacting the base surface (9) of the clamping slot (4) to center the drilling blade (2) with respect to the rotational axis (6) of the holder (1).

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: An adjustable cartridge assembly is provided for a cutting head of a machine tool. The cartridge fixes the back rake angle of the cutting blade so that mere radial adjustment is required to adjust the blade. Moreover, the cartridge includes a support portion that matingly receives the blade and provides support along three contiguous surfaces.

Abstract: This Improved Rotary End Cutting Tool is a completely new concept in twist-drill theory, design, and method of construction. Which will revolutionize the rotary end cutting tool systems as presently known today; especially in larger drill (30) diameters. The new concept of an incurvate cutting-edge (38), purposely orchestrated and offset volumetric grooves (41) combined with a tapered residual core-area (50) in the forward conical forward-end, along with all other renovative improvements. Has virtually resolved drill-chatter, rapid dulling, poor centering, penetration, and even breakage; naming just a few from a list of problems inhabiting currently marketed twist-drills (30). With the overall combined improvements, being to extensive to list herein, having afforded a uniquely simple insert cutting-unit (47) displaying a fixed and removable version capable of equally performing as well as its one-piece counterpart twist-drill (30).

Abstract: A cutter blade is provided having a cutting face. Formed in the cutting face are a plurality of spaced apart slots, each slot having forward and rearward sidewalls. A tooth is removably received in each of the slots, each tooth having a top surface extending above the cutting face and having forward and rearward sidewalls, The top surface of each tooth has a forward cutting edge and a rearward reduced height step section. A retention bar is provided for each tooth, each retention bar having a forward end that is received in the step section. A pin extending through an opening in each retention bar is threadably connected to the cutting face. By tightening the threaded pin the retention bar retains each tooth during cutting operation so that the tooth sidewalls frictionally engage the slot sidewalls and by unthreading the pin the retention bar may be rotated to permit removal and replacement of each of the teeth.

Abstract: In a machine reamer a cutter is guided in a guide slot in the main body and is supported at one end against a pin-shaped axial adjuster. The axial adjuster is a hollow cylindrical stop pin whose slotted pin head can be radially expanded by means of a countersunk head screw, whereby the cutter supported against it is sensitively moved in the direction radial to the axis of the pin.

Abstract: A drilling tool for drilling bores in solid metal, with a shank having at its front end several geometrically similar indexable inserts arranged at various radial distances and staggered with respect to each other by the same peripheral angle, whose working areas overlap, each of them having two equally long cutting edges, two of the respectively contiguous cutting edges inclined with respect to each other at an obtuse angle being simultaneously engaged, whereby the radial inner indexable insert extends slightly with one of its engaged cutting edges beyond the drill axis, at least one of the bisectors of the two pair set cutting edges of indexable inserts being inclined with respect to the longitudinal shank axis by an angle up to 25.degree. m and at least one of the bisectors running at an angle differing from zero with respect to another bisector, so that the sum total differing from zero of the radial force component (F.sub.

Abstract: A drill with indexable inserts has one center insert (11) and one peripheral insert (12), said center insert having a symmetric drill point (25) on the drill axis (10) with a transverse edge which is continuous with one short edge (27) and one long edge (21,23) and a screw hole offset from the symmetry axis of the drill point (25) towards the side of the long edge (21,23).

Abstract: A drill has a pair of cutting edges (4) which are arranged at positions that are substantially uniformly circumferentially spaced about its rotation axis. Each of the cutting edges (4) has a first linear cutting region (4a) and a second linear cutting region (4b) which are aligned with each other on the same straight line, and a curved cutting region (4c) which is located between the first and second linear cutting regions (4a, 4b). The curved cutting region (4c) has a third linear cutting region (4e, 4f) which extends in a direction intersecting with the second linear cutting region (4b) at a prescribed angle. With this structure, it is possible to prevent chip loading etc. which may be caused during perforation drilling operations. In a throw-away tipped drill, a notch (118a) is formed in a received portion of an insert (110) which is mounted on a shank (130). A holding portion (131a, 131b, 133a, 133b) of the shank (130) corresponding to the notch (118a) is provided with a through screw hole (138).

Abstract: A surgical device having a surgical element removably connected to a drive element so that drive torque is transmitted to the surgical element as the drive element rotates, while allowing the surgical element at least one degree of freedom of motion relative to the drive element; a retaining element maintains the drive and surgical elements in torque-transmitting relation during operation of the device.

Abstract: A drill of simple construction, using commercially available tips or tips obtained by simply modifying them, well balanced in cutting resistance, and capable of drilling small-diameter holes.A main cutting edge (12) of a center-side cutting edge 1 is situated on a base line VP of a circular cone having its vertex on a point V on a tool central axis OO and a half vertical angle .alpha.. An intermediate cutting edge (2) having a length substantially equal to 1/2 of the length of the main cutting edge (12) is arranged on a straight line V'Q', extending parallel to a base line VQ, which is symmetrical to the base line VP with respect to the tool central axis OO and advanced ahead of the base line VQ for a lip height t mm in the axial direction, so that a straight line connecting the respective middle points of the intermediate cutting edge (2) and the main cutting edge (12) intersect the tool central axis (OO) substantially at right angles.

Abstract: A plunge cutting device for plastic pipe, pipe couplings, plastic flanges and other planar members includes a cylindrical body including slots formed therein, a pilot for guiding the cylindrical body, and cutters adjustably mounted in the slots. A canted relief is formed in the cylindrical body adjoining the leading wall of each slot to facilitate ejection of cut shavings. The pilot may comprise a main pilot and an auxiliary pilot detachably connected to the main pilot. The auxiliary pilot can be replaced with one of a different diameter in accordance with the dimensions of a pipe being processed with the device.

Abstract: A cutting tool for making cylindrical bores includes two or More cutting inserts and radially or approximately radially directed blades which leave an uncut core, as well as chip removal devices extending in the axial direction of the tool. The cutting tool is composed of at least two coaxial parts. One part forms the boring crown with the cutting inserts, and the other part forms the support for the boring crown with a clamping shank. The chip removal devices extend axially along both parts and lead radially to the outside.

Abstract: A universal plunge cutter for plastic pipe, pipe couplings, plastic flanges and other planar members, is provided. The plunge cutter has a cylindrical body supporting cutters, a drive shaft, a pilot mandrel for guiding the cylindrical body. The cutters are adjustably mounted in cutter slots formed in the cylindrical body so that the cutters present forwardly facing cutting edges which lie skewed relative to a radius of the cylindrical body. A method for the use of the plunge cutter is also provided.

Abstract: This patent discloses a method of manufacturing an insert drill having three or more flutes and a three flute insert drill that may be manufactured by the disclosed method. The method allows accurate machining of insert pockets without requiring removal of a large volume of material from an adjacent flute. The drill disclosed by this patent has three or more cutting inserts which cut chips that are smaller than drills of similar size that have a smaller number of cutting tip inserts. Smaller chips allow easier evacuation of chips and enhance cooling of the drill and workpiece.

Abstract: An indexable insert drill for producing a hole in a workpiece by relative rotary motion between the drill and workpiece. The drill comprises an elongated body having a central axis and a leading end, and a plurality of cutting inserts mounted on the leading end of the body. The cutting inserts are displaced at different radial locations relative to the central axis of the body. Each cutting insert has a cutting edge formed by a pair of respective inside and outside active cutting edge segments with the inside cutting edge segment being located closer to the central axis of the body than the outside cutting edge segment thereof. The inside and outside cutting edge segments of the respective cutting inserts extend at obtuse angles to one another and define therebetween apexes which are axially displaced at different distances from a plane normal to the central axis of the drill at the leading end of the drill which distances increase in length from an innermost one of the inserts to an outermost one thereof.

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 spot drilling and centering drill including a body having a cylindrical head portion and a replaceable indexable insert mounted in the head portion. A V-angled slot is formed directly in the head portion. The insert has two V-angled cutting surfaces with a drill point, each cutting surface fitting within the V-angled slot to locate the drill points on the centerline of rotation of the drill.

Abstract: A circle cutter includes a beam with a central arbor and a pair of tool holders concurrently oppositely adjustable along the beam and having a pair of vertically spaced longitudinal bores carrying screws for engaging cutting members. An extension member engages the tool holder outer face and is detachably attached by screws engaging bores in the extension member and those in the tool holder and used for securing a tool to the extension outer face. A threaded third bore is formed in the extension below the first pair permitting the vertical adjustment of the attached tool.

Abstract: A throw-away tipped drill has an insert removably connected to a shank for cutting a workpiece. The insert (31) and the shank (32) have mutually engaging surfaces respectively, and a slit (34, 39) is formed either in the insert (31) or in the shank (32) for mounting the insert to the shank, whereby the insert (31) is fixed to the shank (32) by an elastic force which is caused by an elastic deformation upon mutual movement of opposite surfaces of this slit (34, 39) in engagement of the insert (31) and the shank (32). Therefore, the insert (31) and the shank (32) are coupled by simple press fitting without any requirement for a screw or other connection, whereby the assembly is improved.

Abstract: A cutting tool for expanding or opening up the diameter of boreholes includes at least one reversible knife plate with a front surface. The knife plate can be clamped with at least one clamping shoe into a recess provided in a cutter head. The front surface of the knife plate has at least two grooves which extend essentially parallel and preferably symmetrical with respect to the longitudinal axis of the knife plate. The grooves cooperate with projections provided on the contact surface of the clamping shoe facing the front surface of the knife plate and form a positively locked connection therewith.

Abstract: A drill and trimming attachment assembly is disclosed for drilling holes with beveled top openings in a work piece. The assembly includes a drill shaft with at least one longitudinally extending groove formed therein. A trimming attachment suitable for clamping to the drill shaft is also provided to form a beveled recess at the top of a hole formed by the drill. The trimming attachment includes a body and a trimming blade having base and arm portions. The base portion of the trimming blade is detachably secured to the body, and the body is arranged to be removably journaled about and clamped to the shaft of the drill such that an edge of the arm portion of the trimming blade is closely received by the groove. Thus, during use, the groove carries at least a portion of the load acting against the trimming blade.

Abstract: A tool for use in machine-tools with a cutting head (14) has at least one interchangeable cartridge (24) which can be releasably fastened to the cutting head and which carries an interchangeable insert. The interchangeable cartridge can be adjusted on the cutting head in the advance direction of the insert by the action of an adjustment mechanism. The adjustment mechanism has a tapered ram (46) which can move along a guide (42) of the cutting head (14) arranged parallel to the plane of the insert and essentially perpendicular to the advance direction of the cutting head (14). The tapered ram has a tapered surface (44) which is inclined at an acute angle to the direction of sliding and which is contiguous with an inclined shoulder (54) of the interchangeable cartridge which makes a right angle, in the direction of the inclined tapered surface, with the advance direction.

Abstract: A center vacuum rotary drill bit including a drill bit body having a top working surface. Formed within the top working surface is a slot having disposed therein an insert positioned within a shim within the slot. The insert includes a pair of oppositely facing generally parallel side surfaces, a pair of oppositely facing generally parallel end surfaces extending between and interconnecting said side surfaces, a pair of oppositely inclined top surfaces extending between and interconnecting said side and end pairs of surfaces, and a bottom surface having a concave depression formed therein. The bottom surface extends transversely to and interconnects the side and end pairs of surfaces. A support bar including a convex top surface is disposed within the slot between the insert bottom surface and the slot such that the convex top surface supports the concave depression of the insert. In a preferred embodiment, the modulus of elasticity of the support bar is greater than the modulus of elasticity of the shim.

Abstract: A drill is provided having a generally cylindrically shaped body. The body has a rear end structured to releasably connect with a torque transmitting machine in a conventional manner. The body has a forward end which is provided with diametrically opposed seats. Each seat releasably retains a cutting insert. Each cutting insert has a cutting edge projecting forwardly from the forward end of the body. Further, the cutting inserts are oriented so that one cutting edge is at a ten degree positive lead angle and the other cutting edge is at a five degree negative lead angle, the angles being measured normal to the center line of the drill. In operation, the drill is used to provide a bore hole in a workpiece, the bore hole having a predetermined perimeter. As the rotating drill contacts the workpiece, the cutting edges contact the workpiece in a predetermined, progressive manner which thereby creates a plurality of spaced apart circular notches of differing depth in the workpiece.

Abstract: A combined hole cutting and chamfering tool is provided that in a preferred embodiment referenced by numeral (100) features a body member (2) having a lead section ("A") to which is secured a cutting bit (4) having a machining element such as a hole cutting edge (6). Spaced axially from section ("A") is a chamfering section ("B") having at least one chamfer machining element such as cutting edge (12) of a cutting bit (14) facing towards section ("B") and at least one chamfer machining element such as cutting edge (8) of cutting bit (10) facing away from section ("A") and closer thereto than cutting edge (12). Tool (100) is operative to cut a hole (18) through a workpiece such as a plate and then chamfer edges surrounding the hole on opposite sides of the workpiece from one side without having to remove tool (100) from hole (18).

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 drill bit has a throw-away drill bit tip in the form of an insert (21, 31) secured to a shank (22, 32) to be mounted in a drilling tool. The insert (21, 31) is disengageably mechanically connected to the shank (22, 32) without any screws. The insert (21, 31) is formed of a silicon carbide whisker reinforced alumina sintered body, and the shank (22, 32) is made of steel. Due to this structure, the insert (21, 31) has an excellent wear resistance and an adhesion resistance. The shank (22, 32) has a sufficient toughness against breakage. Such a drill bit does not require any resharpening for continuous use during bit life.

Abstract: A drill bit has a throw-away drill bit tip in the form of an insert (21, 31) secured to a shank (22, 32) to be mounted in a drilling tool. The insert (21, 31) is disengageably mechanically connected with the shank (22, 32) without any screws. At least a cutting edge of the insert (21, 31) is made of a diamond or cubic boron nitride sintered body, and the shank (22, 32) is made of steel. Due to this structure, the insert (21, 31) has an excellent wear resistance and an adhesion resistance. The shank (22, 32) has sufficient toughness against breakage. Such a drill bit does not require any resharpening for continuous use during bit life.

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 drill bit of a diamond-coated sintered body has a substrate mainly composed of Si.sub.3 N.sub.4 or SiC. At least a wear portion of the bit is coated with a diamond layer. If the bit is of the throw-away kind, an insert is removably secured to a shank. At least the insert or a wear portion thereof is coated with a diamond layer. The sintered body contains a prescribed amount of a sintering assistant or aid selected from MgO, Y.sub.2 O.sub.3 and the like. The diamond coating layer has a thickness of at least 0.1 .mu.m.

Abstract: A metal cutting drill with two replaceable cutting inserts which are positioned to cut the full circumference of a hole during each one-half revolution of the drill. Each insert is triangular and includes an active cutting edge having a curved corner to enable the insert to cut near the center of the hole. Each insert may be inverted and indexed in order to bring an alternately usable cutting edge into active cutting position. By virtue of the inserts being triangular, the curved corners on the cutting edges of the two inserts may be positioned relatively close together and yet sufficient space is left between the inserts to enable the drill body to be relatively thick and strong.

Abstract: Tooling to form a countersink or counterbore in a workpiece, the countersink or counterbore intersecting a bore hole in the workpiece, comprises a first part defining an axis to extend axially forwardly in the bore hole; a carrier body having a forward portion for piloting reception in the bore hole, and having a rearward portion adjustably carried by the first part; a cutter blade on the carrier, the blade projecting radially relative to the carrier body and forming at least one cutting edge shaped to form the countersink or counterbore; and a spacer on the carrier body and adjustably retained between the first part and the blade for holding the blade in predetermined axial position on and relative to the carrier body.

Abstract: A cutting tool assembly is disclosed as having a cutting blade of U-shape and a holder with flexible arms which may be expanded to grip the cutting blade.

Abstract: A rotatable arbor-type tool for use in a portable power drill is provide for sharpening the ends of metal studs and particularly snowmobile tread studs or spikes. The tool has a cylindrical head with a tapered central opening axially aligned with the axis of rotation of the head. Radial grooves extend from the central opening through the wall of the head to the outer surface thereof. One wall of each groove constitutes an abutment wall against which a preferably triangular cutting blade having a thickness substantially less than the groove width is positioned. The cutting blade is forceably held against the abutment wall by a set screw extending against the cutting blade from the opposite wall leaving an opening extending along the groove past the cutting tool sufficiently wide to provide an exit from the central opening for chips cut from the end of the stud by the cutting edges of the cutting tool. The abutment wall is that wall which faces the direction of rotation of said head.

Abstract: Counterbore milling cutter employing Trigon inserts mounted with the active cutting edge extending radially to provide right angle counterbore corners with 84.degree. included angle cutting points for greater strength and support than possible with conventional triangular inserts. A pair of pocket shoulders at the end of the body adjacent a pilot extension locate each insert held by a central screw offset toward the pocket shoulders, preferably configured to best resist torque imposed by axial force against the cutting edge.

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: Boring apparatus includes a multiple start screw to secure a cutting piece to a boring bar. The multiple start screw prevents loosening of the cutting piece during use of the boring apparatus. The multiple start screw also enables easy changing of the cutting piece or repositioning of the cutting piece between periods of use of the apparatus.

Abstract: A universal tool for inspecting and processing plastic pipe includes a cylindrical chamfering element with a cylindrical wall and a pipe-receiving opening therein terminating in a base ring, the base ring carrying a tapered pin having an axis parallel to the axis of the cylindrical chamfering element, the wall of the chamfering element having a slot therein proximate the tapered pin and a four-edged cutting element mounted on the outer surface of the cylindrical wall and having one edge of the cutting element protruding through the slot in proximity to the tapered pin, the pipe to be chamfered being forced into contact with the cutting edge by axial pressure on the chamfering element and rotation thereof, an ovality-gage being carried by the chamfering element and being arcuatley rotatable, at the end of the arc rotation of the gage causing rotational forces to be applied to the chamfering element, i.e., the ovality-gage acting as a handle for the chamfering element.