Abstract: A deep hole cutter for a gun drill system includes a tool shank and a cutting head with two or more cutting edges. The tool shank and the cutting head are separate members connected strongly by threads. The shavings produced by the cutting edges can be discharged together with the coolant supplied through the hole cutter. The shaving dischargeability is improved for higher cutting efficiency. The tool shank 1 has one outer axial discharge groove 3. The cutting head 2 has one outer axial discharge groove 6 in linear alignment with the discharge groove 3. The cutting head 2 also has a discharge port 7a formed in its front end. The cutting head 2 further has a bypass passage 7 formed in it and extending between the discharge port 7a and the discharge groove 6. The cutting edges 9a and 9c face the discharge groove 6. The cutting edge 9b faces the discharge port 7a.

Abstract: A milling cutter includes a body having three cutting edges formed by the body. An end of the body situated opposite the cutting edges defines a fastening end of the milling cutter. Each cutting edge extends from an outer periphery of the body substantially to a center rotational axis of the body along a substantially convexly curved path. Radially outer and radially inner ends of each cutting edge are situated axially rearwardly of an axially foremost point of the cutting edge. Each cutting edge lies on a respective imaginary sphere having a radius which has a center which that is spaced from the cutting edge in a direction toward the fastening end and spaced radially from the center axis.

Abstract: A cutting tool insert having a controlled contact clearance behind the cutting edge which limits flank wear and allows more coolant near the cutting edge further allowing an increase in surface speed, feed rates, and tool life. The controlled contact clearance surface provides a first wear zone and a second wear zone, the first wear zone generated during operation of the drill insert allows the flank wear distance to grow from zero to the distance from the cutting edge to the controlled contact clearance surface, the second wear zone keeps the flank wear distance substantially constant until the controlled contact clearance surface is substantially worn away.

Abstract: The invention relates to a drill, especially a Forstner bit or a multi-spur machine bit having a drill shaft and a cutter head and provided with a central mandrel, a first and second spur cutter radially extending towards the outside from said mandrel and in opposite tool approach directions; a respective hollow cylinder segment wall has a circumference cutter defining the circumference of the cutter head and is joined to the ends of the first and second spur cutter, said ends facing the circumference, wherein the wall defines a chip space facing away from the spur cutter and opening to the respective remaining spur cutter and leading to the drill head, and wherein the two cutters are provided with wave-shaped cavities and elevations at least partially along the sides thereof.

Abstract: A centering feature (230) on a drill bit (110) configured without a pointed tip, formed as an opening (230) between first (206) and second (208) relatively angularly inclined portions of a work engaging end (116) of the drill bit (110). The first portion (206) of the work engaging end (116) is defined by a cutting edge (134), and the second portion (208) is defined by an end face side boundary (216) transversely aligned with the cutting edge (134). The cutting edge (134) and end face side boundary (216) are offset from each other to create the opening (230), which permits the drill operator to view a punch mark or other indication on the work piece where the center (232) of the intended hole is to be located. The drill operator positions the medial termination point (212) of the cutting edge (134) of the drill bit (110) over the center hole location (232) preparatory to contacting the drill bit (110) against the work piece to cut the hole.

Abstract: Metal cutting tools, such as drills or reamers, utilized to produce holes with substantially improved finishes and sizes at faster speed and feed rates having a double cutting action, said tool comprising a reamer having a plurality of cutting flutes with a 45° primary cutting surface and a tapered secondary cutting surface, the primary surface including slots or grooves thereon, and each flute may have a margin on the O.D. of the flute or a relief angle to provide accurate cutting operations.

Abstract: This bit has an axis and a tip end with an obtuse angle. There are multiple scraping surfaces, each facing counter-clockwise into a longitudinal recess in the tip end. Each scraping surface has a scraping edge at an angle of about 55° to 70° to the axis. Behind each scraping surface the outer surface of the tip end curves down to a rearward edge adjacent another of the longitudinal recesses, the rearward edges each being disposed at a sharper angle to the axis than the scraping edge so that there is some relief, allowing the scraping edge to be more pronounced and enhance its ability to dig into the metal of a deformed screw at points removed from the axis to get a good purchase on the screw.

Abstract: A reamer includes: (a) an axially-distal-end small-diameter portion; (b) a guide portion which is axially adjacent to the small-diameter portion; (c) at least one flute which is formed in an outer circumferential surface of the reamer and which extends from the axially distal end of the reamer toward the axially distal end of the reamer; and (d) at least one land surface which is circumferentially adjacent to the flute. The land has a cutting blade portion formed therein in the axially-distal-end small-diameter portion. A first radial distance from an axis of the reamer to a radically outer end of the cutting blade portion is larger than a second radial distance from the axis to the land surface in the axially-distal-end small-diameter portion. The first radial distance is smaller than a third radial distance from the axis to the land surface in the guide portion.

Abstract: This invention describes a drilling plate and bracket for the drilling plate for machining drilled holes in work pieces, whereby the bracket for the drilling plate is designed so that it is somewhat pin-shaped and holds the drilling plate on its front side. It is characterized in that the drilling plate (1) is designed with an enlarged sheet thickness in the area of the cutting geometry in which chip breaking contours (15, 16, 20) are formed.

Abstract: A reamer for the fine machining of surfaces of drilled holes in metal workpieces has a reamer body and at that body has at least one main blade and at least one auxiliary blade, a chip surface adjoining the blades at one side and a chip deflector step limiting the chip surface. That deflector step falls away in the zone of the auxiliary blade, exhibiting an increasing distance from the auxiliary blade. The chip deflector step rises in the zone of the main blade, exhibiting a decreasing distance from the main blade. The blades, chip surface and deflector step may be on a cutter plate attached to the reamer body or be part of the body itself. The invention also concerns that cutter plate.

Abstract: This invention describes a drilling plate and bracket for the drilling plate for machining drilled holes in work pieces, whereby the bracket for the drilling plate is designed so that it is somewhat pin-shaped and holds the drilling plate on its front side. It is characterized in that the drilling plate (1) is designed with an enlarged sheet thickness in the area of the cutting geometry in which chip breaking contours (15, 16, 20) are formed.

Abstract: A force balanced irregular pitch reamer is provided that is particularly well suited for precision operations requiring small tolerances. More specifically, a reamer is provided having a shank, a body portion, and a plurality of cutting teeth extending outwardly therefrom. The teeth are spaced at non-uniform intervals around the body portion, wherein each tooth includes a cutting surface and rake face, and defines a rake angle between the rake face and an imaginary line extending from the central or longitudinal axis of the reamer to the cutting surface. In operation, the reamer is rotated about its central axis and is plunged into a formed hole sized slightly smaller than the reamer such that the reamer engages the workpiece and produces a smooth finished hole. Each tooth generates a cutting force with determinable magnitude and direction to define cutting force vectors.

Abstract: An improved twist drill is provided which reduces wear or chippings of the major cutting edges (3) and those of the leading edges (7) of land (9) and which has a long service life and stays sharp. A twist drill has a pair of chip discharge flutes (6), a pair of chisel edges (1), a pair of inner cutting edges (2) and a pair of major cutting edges (3) extending from each outer end of the inner cutting edges (2). Further, the drill has a pair of outer cutting edges (4) each receding from each of the major cutting edges (3) at an angle (&agr;1), and a pair of leading edges (7) of lands (9) each formed by the land (9) and the outer cutting edge (4) and has a linear or curved rake face (8). Wherein, an angle (&agr;4) of the leading edge (7) of land (9) between the leading edge (7) of the land (9) between the leading edge (7) of the land (9) and the linear or curved rake face (8) is an obtuse angle.

Abstract: This bit has an axis and a tip end with an obtuse angle. There are multiple scraping surfaces, each facing counter-clockwise into a longitudinal recess in the tip end. Each scraping surface has a scraping edge at an angle of about 55° to 70° to the axis. Behind each scraping surface the outer surface of the tip end curves down to a rearward edge adjacent another of the longitudinal recesses, the rearward edges each being disposed at a sharper angle to the axis than the scraping edge so that there is some relief, allowing the scraping edge to be more pronounced and enhance its ability to dig into the metal of a deformed screw at points removed from the axis to get a good purchase on the screw.

Abstract: Apparatuses and methods are implemented for machining a longitudinally extending slot in a bore of a component. The component is gripped in a gripping device of a workholding device. A cutting operation is performed in order to cut the slot in the bore by a cutting tool. The cutting operation forms burred slot edges. The edges are further machined by inserting a deburring device into the bore. Relative angular reciprocation for a limited angle is imparted between the deburring device and the component.

Abstract: A boring bit, especially a multi-blade boring bit. The bit preferably has a point symmetric cutting edge arrangement having main and secondary cutting edges that are tilted towards the axis of the boring bit. In order to stabilize the tool against vibrations cased by the cutting force, the secondary cutting edge is tilted along an effective length that is substantially axial in the direction of cutting thereby having a negative tool side rake.

Abstract: A rotary pipe cutting apparatus for removing sections of broken pipe from the bore of an outer pipe. The invention includes a cylindrical body with a longitudinal slot that is angularly offset from the rotational axis of the body and which is tapered in depth and width from top to bottom. A blade is included on the body adjacent the slot and the lower end of the body, with the blade having cutting edges which extend both downward and radially outward from the body. A guide member which centers the apparatus is included on the lower end of the body which includes resilient rounded projections. A stopping member is included on the upper end of the body. A shank on the upper end of the body allows attachment of the apparatus to a rotary power tool.

Abstract: Significantly improved resistance to breaking while drilling in metal can be realized in twist drill bits having a web thickness taper which is about twice the web thickness taper specified in Standards and in common use in the industry. This creates much shallower flutes and flies in the face of conventional wisdom in the art which holds that the web taper rate should be low to maximize the amount of flute volume available to convey chips and sawdust out of the hole. A flute length of about 1/2″ less than the flute lengths specified by the Standards makes it possible to have such a large taper rate but still control variations in tolerances for the flute length. It also provides a marking zone for placing size indicia on the drill bit shank outside the portion which is gripped by the chuck jaws of a power drill.

Abstract: A rotary shaft tool for machining bores, particularly blind hold bores, has a shaft with at least one longitudinal conduit for coolant/lubricant, with a cutter head that has at least one cutting edge and a chip space. A chip space section is provided that tapers toward the end of the cutter head.

Abstract: A helical twist drill has fluted lands each having projecting from their radially outer faces a plurality of circumferentially spaced support margins. At least one of the support margins is asymmetrically spaced with respect to the other support margins.

Abstract: Significantly improved resistance to breaking while drilling in metal can be realized in twist drill bits having a web thickness taper which is about twice the web thickness taper specified in Standards and in common use in the industry. This creates much shallower flutes and flies in the face of conventional wisdom in the art which holds that the web taper rate should be low to maximize the amount of flute volume available to convey chips and sawdust out of the hole. A flute length of about 1/2" less than the flute lengths specified by the Standards makes it possible to have such a large taper rate but still control variations in tolerances for the flute length. It also provides a marking zone for placing size indicia on the drill bit shank outside the portion which is, ripped by the chuck jaws of a power drill.

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: A generally cylindrical drill, particularly an insert drill having multiple cutting inserts, helical chip grooves to clear the chips from the hole, and a gripping shank opposite the cutting end of the drill, wherein the drill experiences an unbalanced resultant transverse force upon the cutting tip of the drill, and that resultant is oriented perpendicularly to an axial plane containing the neutral axis of the maximum resistive moment at the grooved section of maximum bending stress adjacent to its juncture with the gripping shank.

Abstract: A drill for metal chip-removing machining includes a shank which defines a longitudinal axis of rotation and has front and rear ends. The front end carries cutting edges defined by respective inserts. Two chip flutes extend rearwardly from respective cutting edges for conducting chips. A cooling channel includes a main portion extending through the shank between the two chip flutes. At a location spaced from the front end of the shank, the main portion of the cooling channel splits into two branch portions which terminate in the front end of the shank. The main portion of the cooling channel is arranged such that a center axis thereof lies parallel to, and radially offset from, the axis of rotation, and such that the axis of rotation lies within the main portion of the cooling channel.

Abstract: A short-hole drill bit and short-hole drilling method in which a drill bit has a unitary body with a substantially V-shaped flute and a support pad are provided. The unitary body has a shank portion and a working portion. The flute extends axially along the working portion, and defines a cutting edge and a passive edge at the body periphery. The support pad is located along a portion of the body periphery. The support pad is located with respect to the cutting edge based on a normal cutting force and a tangential cutting force at the cutting edge. The resultant cutting force is directed at the support pad to cause the support pad to center the short-hole drill bit during operation.

Abstract: A rotary pipe cutting apparatus for removing sections of broken pipe from the bore of an outer pipe. The invention includes a cylindrical body with a longitudinal slot that is angularly offset from the rotational axis of the body and which is tapered in depth and width from top to bottom. A blade is included on the body adjacent the slot and the lower end of the body, with the blade having cutting edges which extend both downward and radially outward from the body. A detachable and interchangeable guide member is included on the lower end of the body, and a stopping member is included on the upper end of the body. A shank on the upper end of the body allows attachment of the apparatus to a rotary power tool.

Abstract: A drill is provided with a pair of spiral cutting blades having opposed cutting edges to come together at an angle to form a starting tip. Each of the spiral cutting blades includes a primary and a secondary flute which extends longitudinally thereof and is provided with cutting edge segments thereon, one flute being provided with an outer cutting edge segment and a second flute being provided with an inner cutting edge segment. The outer cutting edge segments of each cutting blade are in axial alignment with each other and the center point of the drill bit and perpendicular to an arcuate segment of the outer periphery of the drill.

Abstract: A rotating boring tool (10) comprises a cylindrical shank (11) and a body (12), both of which are coaxial with each other, said body being provided at its tip end with cutting blades (13a, 13b) which are in point symmetry with respect to an axis of the shank. Provided on the body are two flutes (14a, 14b) continuous from the cutting blades. The both flutes are made to approach each other at the lower half lead portions (designated hereinbelow as f1 portions) of terminal end portions f0 of the flutes and positioned about 35 degrees or more offset from the position of point symmetry. Alternatively, the both flutes are merged at the f1 portions. Accordingly, thickened portions y0 are formed on the f1 portions to increase rigidity of the f1 portions. As a result, it is possible to suppress generation of fatigue failure at the f1 portions whereby a rotating boring tool of long service life which is hard to break is obtained and a product cost and a cost for tool replacement are considerably reduced.

Abstract: A drill including an elongate shaft (2) a rear end (5) of which is formed as a shank, and a drilling head (10) provided at the front end of the shaft (2) and having central cutting edges (11, 12) extending from a leading center point (14), which is provided substantially at an extension of a shaft axis, backward toward a circumference of the drilling head, and at least one minor cutting edge (13) a portion (n) of which extending transverse to the shaft axis projects beyond a circumference of the shaft (2), with the projecting portion (n) having a length equal from about 10% to 100% of an entire length of the minor cutting edge.

Abstract: A two-fluted countersink tool for countersinking holes comprising a holder and removable cutting inserts. The cutting holder having a body with two portions removed to define a first and second pocket. Each insert has first and second ends, first and second lateral surfaces, first, second and third top surfaces and a bottom surface. The cutting surface of each cutting insert extends from an edge of the third top surface. The cutting surface has a first cutting edge and a second cutting edge.The cutting inserts are positioned inside the pockets and are attached to the holder such that the cutting edge remains as close as possible to the centerline of the countersink tool.

Abstract: A metal cutting drill with replaceable cutting inserts and a length to diameter ratio of four to one or more. Two cutting inserts are positioned in exactly opposed diametric positions, and engage the workpiece in a substantially identical manner to precisely balance the radial forces resulting from drill axially advancing though a workpiece. Through the use of dual cutting inserts, the drill cuts the full circumference of a bore with each one-half revolution and therefore achieves the a faster axial feed rate. 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 shank between the inserts to be relatively thick and strong even at increased length to diameter ratios.

Abstract: A polycrystalline diamond (PCD) tipped tool for producing holes in non-ferrous and non-metallic composite materials without delamination. The tool comprises an elongated body portion having a distal cutting region and a proximal shank region and first and second cutting regions including first and second planar surfaces, respectively. The planar surfaces diverge in a direction from the distal cutting region toward the proximal shank region to define a cutting angle that is preferably about 120.degree..A first axial flute separates a forward edge of the first cutting region from a trailing edge of the second cutting region and a second axial flute radially opposed to the first axial flute separates a forward edge of the second cutting region from a trailing edge of the first cutting region. Each of the first and second cutting regions further includes a planar surface forming with a forward edge thereof respective first and second clearance angles of between 10.degree. to 20.degree.

Abstract: A screw or tap for forming or cutting threads in a workpiece. The screw includes a cylindrical shank directed along a longitudinal axis. The shank includes a work holding portion having a plurality of helical threads of a constant crest diameter, a constant root diameter, a constant pitch diameter, and circular cross-section. The shank also has a lead portion having at least a portion of a helical thread. Intermediate the work holding portion and the lead portion is a forming portion. The forming portion has at least one full thread located thereon having a crest diameter which is greater than the crest diameter of the plurality of helical threads on the holding portion, a root diameter which is larger than the root diameter of the plurality of helical threads on the holding portion, and a pitch diameter which is proportionally greater than the pitch diameter of the holding portion.

Abstract: A medical drill for drilling holes in a bone or cartilage is formed with an end drill section. The end drill section has a specially formed drill tip at the distal end. The drill tip includes a flattened section which is located diametrically in relation to the central axis of the drill. The drill may be formed on the end of a router to provide a single loop to drill a pilot hole and then continue with the routing process. The drill section minimizes the heat created within the bone or cartilage.

Abstract: The invention relates to a drilling tool (11), comprising a drill shank (22) which has an inner chip space (13) and an outer chip space (14) which extend axially along the drill shank (22) and which in each case accommodate at least one indexable insert (21, 22), the drill shank (12) having a left-hand twist for damping vibrations and increasing the cutting capacity.

Abstract: The invention relates to a drilling tool (11) for bores in solid material, comprising a drill shank (26) which has a radially inner indexable insert (13) at an inner chip space (21) and a radially outer indexable insert (14) at an outer chip space (22), the working areas of which indexable inserts (13, 14) overlap, the inner chip space (21) having a cover (36) which extends at least partly along the shank longitudinal axis (20), and the inner chip space (21) merging into the outer chip space (22), so that the chip discharge is effected via a common chip space (23) in the rear area (32) of the drilling tool (11).

Abstract: A tool having a profile for the forming or shaping of a complementary thread in and/or on a fastener which can be utilized with advantage as a bone screw or another osteosynthetic force transmitting member, instrument or accessory. The thread which is formed by the profile of the tool has two flanks each having a first section adjacent the crest and a second section adjacent the root of the thread. The second sections jointly include or consist of at least four concave portions having different radii of curvature and gradually merging into each other. The first sections make angles of less than 40.degree. with a plane which is normal to the longitudinal axis of the thread. The first and second sections of each flank are separated from each other by an imaginary cylinder having a diameter which matches the pitch diameter of the thread and a longitudinal axis which coincides with or is at least close to the longitudinal axis of the thread.

Abstract: Cutting elements or cutter chips (7, 8) are located on a tool body (1). Cutting chip removal spaces (14, 15) are formed in the tool body in three segments. A first segment (I) adjoins the end face (4) of the drill body and includes at least one cutting element seat (10, 11); a chip removal space extends axially, i.e. straight, or slightly obliquely fluted. A second segment (II), adjacent thereto, is formed partially helically with a twist (21) of less than 90.degree. relative to the tool body axis; the second segment (II) terminates axially at a point where, in operation, the direction of radially acting cutting forces coincides essentially with the primary axis of inertia (0-0) of the geometrical moment of inertia. A third segment (III) adjoins the second segment (II); it is essentially straight-fluted.

Abstract: Disclosed is an all-ceramic drill bit which combines the positive properties of ceramic with a tool geometry adapted to the special features of the material. The drill bit is formed with a groove for the shavings which extends in the axial direction linearly along a surface line.

Abstract: A drill includes a substantially cylindrical holder (10) with a longitudinal axis (X) and a transverse axis (Y) perpendicular thereto, a drill tip (12) in which there is a groove (14) running along the transverse axis (Y) with a groove bottom (16) and groove sides (18',18"), and a cutting insert fitted in the groove having two main cuts (26',26") with forwardly adjacent cutting surfaces (32',32") and two rear surfaces (30',30") opposite a cutting surface on the other side of the transverse axis (Y). The holder has two bores (20',20") in a radial plane (R) of the drill, each of which is in the region of a rear surface (30',30") of the insert (25) and opens into a groove side (18',18"). The longitudinal axes (24',24") of the drillings (20',20") run at an acute angle to the groove side (18',18") and the adjacent rear surface (30',30") of the insert (25).

Abstract: A high performance cutting tool for drilling complex holes in a work piece comprising a body having a shank for rotating the tool with a drilling machine, an intermediate flute portion having a plurality of straight flutes formed thereon, and a forward, nose portion. A unitary insert having a plurality of cutting edges formed thereon is received in a slot formed in the cutter tool so as to be driven thereby in a manner which permits cutting of a complex hole in a work piece when the cutting tool is rotated in the work piece.

Abstract: A metal cutting drill includes a shank having cutting edges at a front end and helical flutes extending rearwardly from respective cutting edges for conductive cutting fluid away from the front end. The cross-sectional area of each flute, as seen in a plane oriented non-perpendicular to an axis of rotation of the drill, becomes progressively smaller in a rearward direction. A helix angle defined by each flute becomes progressively smaller in the rearward direction. An angle formed between the plane and another plane oriented perpendicular to the axis equals the helix angle at the location where the planes intersect each other and the axis.

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 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: A twist drill is disclosed. The twist drill comprises a substantially cylindrical tool body having a rotational axis therethrough, a front portion, a rear portion, a plurality of web thickness, a front flank face, a plurality of flutes formed on an outer peripheral surface thereof and extending to the front flank face, and a land disposed between a pair of the flutes. The flute has a wall portion facing toward the rotational direction of the tool body. A cutting edge is formed at an intersection between the wall portion of the flute and the front flank face. The web thickness at the rear portion of the tool body is smaller than the web thickness at the front portion of the tool body.

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 burnishing drill includes a cylindrical shank and a drill body connected to the shank. Drilling edges, reaming faces and reaming edges are formed on a first reduced-diameter portion, a second reduced-diameter portion and a third reduced-diameter portion located at a foremost end of the drill body respectively. The reaming faces which are located axially at backward positions of the drilling edges and the reaming edges extend radially outward from the foremost end of the drill and incline axially in the rearward direction, and also extend radially outward and incline in the rearward direction with respect of the rotational direction. Since an inner surface of the hole drilled and reamed by the drilling edges and the reaming edges can be further smoothed by the reaming faces, the surface roughness of the finished hole can be much improved.

Abstract: A hole reamer takes a rough, undersized hole to final size while providing better correction of any initial axial mislocation of the hole. A pair of cutting sections, a smaller diameter lead cutting section and a larger diameter trailing cutting section, are axially separated by a relieved section of smaller diameter. The relieved section is small enough in diameter that it does not make contact with the hole, and is longer axially than the hole is thick. When the lead section enters the hole, it is bent off axis slightly, but the reamer shifts back on axis when the relieved section enters the hole. Thus, the trailing, final hole sizing section is back on axis as it works to finish the hole, bringing it closer to the desired axial location.

Abstract: A chamfering tool and method for use in the precision backchamfering of a rotating part. The chamfering tool has a cutting head portion selected to match the size of the surface to be chamfered. Behind the cutting head is a shank portion of reduced diameter which connects the cutting head portion to an enlarged portion which supports the chamfering tool in a fixed tool holder. If the part centerline is not aligned with the rotating collet centerline, the part center traces a circular orbit. The shank portion of reduced diameter enables the tool to flex so that the cutting head can follow the part centerline being guided by the part's inner diameter.

Abstract: A high speed burnishing drill having drilling edges and reaming edges provided at the forward end of a cylindrical drilling body. The drilling edges are inclined diametrically from the center of the forward end to the axially rearward direction, while the outermost peripheral wall of the drilling edges are on a reduced-diameter portion of the maximum external diameter of the drill body. The reaming edges extend from the plane intersecting the drilling edges radially from a position inward of the outermost peripheral of the drilling edges, outwards, so as to incline axially in the forward direction with a second cutting angle. A reduced diameter portion extends axially backward from the outermost peripheral wall of the drilling edges. An enlarged-diameter guide face extends axially from a slope behind the corresponding drilling edge in the rotational direction, and the forwardmost end of the enlarged guide face is located axially behind the corresponding reaming edge.