Abstract: A bit for removing a broken fastener comprises a tip from which extend two or more notches separated by traction or biting surfaces formed from two-sided frusto-conically-shaped regions. The surfaces are bounded on one side by a nonlinear cutting edge and on the other side by a non-cutting edge and are configured to cut into the fastener when the bit is rotated in a direction opposite to the fastener's direction of engagement. Specific embodiments include configurations where the cutting edges extend at different angles with respect to the bit axis, where the biting surfaces comprise a plurality of serrations, and where the cutting edges are separated by flutes which spiral along a longitudinally extending periphery of the bit.

Abstract: A tool for removing a damaged lug stud from a vehicle may include, at one end thereof, a socket that fits over a lug nut. The socket may be held in place with a wrench, pliers, or the like while the stud is drilled through a bushing on the other end of the tool. The tool may remove the damaged lug stud quickly, without damage to the wheel of the vehicle.

Abstract: An extractor tool for Torx brand and other fluted fasteners comprising an end section for engaging a fastener opening comprising six equally spaced, uniformly sized, pitched flutes separated by uniform depth grooves located at the end of a shank with a cylindrical connecting section joined thereto, in turn, joined to an impact drive end of the shank. The fluted end section has a frusto-conical configuration with the narrow dimension of the fluted end section at the distal end of the tool and wherein the distal end has a flat surface transverse to the longitudinal axis of the shank.

Abstract: A prior art sucker rod tong is improved to remove a coupling completely from a sucker rod assembly comprising sucker rods joined end to end by couplings. The prior art sucker rod tong has a rotatable jaw assembly and a lower backup wrench adapted to cooperate to unscrew a coupling joining first and second rods, where the coupling remains screwed to the second rod after it is unscrewed from the first rod. The improvement comprises a coupling extractor for unscrewing the coupling from the second rod so that the coupling can be replaced. The coupling extractor comprises a shaft having an extractor end portion on each end of the shaft and a shield around each extractor end portion, wherein the coupling extractor is designed and sized to fit within and to be rotated by the jaw assembly. The extractor end portion engages the inside wall of the coupling to unscrew the coupling from the second rod. The extractor end portion is preferably a tapered, left-handed spiral fluted easy-out extractor.

Abstract: A device to extract a fastener from a workpiece. The device includes a shaft having first and second end portions and, a cutting end tool adapted to engage and bore into the fastener as the shaft is rotated, a drill bit portion proximal to the cutting end tool and adapted to engage and bore into the fastener, and a socket disposed about the shaft and a collet collar disposed about the socket.

Abstract: A prior art sucker rod tong is improved to remove a coupling completely from a sucker rod assembly comprising sucker rods joined end to end by couplings. The prior art sucker rod tong has a rotatable jaw assembly and a lower backup wrench adapted to cooperate to unscrew a coupling joining first and second rods, where the coupling remains screwed to the second rod after it is unscrewed from the first rod. The improvement comprises a coupling extractor for unscrewing the coupling from the second rod so that the coupling can be replaced. The coupling extractor comprises a shaft having an extractor end portion on each end of the shaft and a shield around each extractor end portion, wherein the coupling extractor is designed and sized to fit within and to be rotated by the jaw assembly. The extractor end portion engages the inside wall of the coupling to unscrew the coupling from the second rod. The extractor end portion is preferably a tapered, left-handed spiral fluted easy-out extractor.

Abstract: A tool head structure is used to screw a regular screw or a damaged screw and comprises two cutting portions located at the center of the front portion thereof. Between the two cutting portions is formed a ridge line, and behind the two cutting portions are formed two concave flank portions, and the respective flank portions are correspondingly linked up with scraping grooves. By such arrangements, the tool head structure can solve the problems of easy slipping and being unable to remove the damaged screw.

Abstract: A kit for removal of a broken spark plug from a cylinder head includes first and second tools. The first tool is designed to position a broken porcelain element into the spark plug tip so that the second tool may be utilized to engage the tip by threading into the tip and thereafter axially withdraw the plug tip from the cylinder head by rotation of the tool.

Abstract: Disengagement and removal tool consists of five metal parts, which can easily remove swollen glow plug without exposure to break and despite the narrow area between the engine and the body of the vehicle.

Abstract: A bit for removing a broken security fastener having an elongated shaft with a longitudinal axis. The shaft has a first end and a second end. The first end terminates in a tip region having a recess for receipt of the post of the security fastener, the recess being disposed substantially along the longitudinal axis. The second end of the shaft is configured to be received by the chuck of a tool which provides rotational torque.

Abstract: An improved hand tool for use with threaded rods, comprising a pair of partially threaded jaws whereby said partial threads of each jaw mate with the thread of the threaded rod, such that the jaws may be clamped onto either side of a threaded rod by a clamping device and simultaneously rotated, causing the threaded rod to rotate along with the jaws without damage to the thread of the threaded rod.

Abstract: A fastener removing tool is provided. The fastener removing tool includes an extractor portion having an inside surface adapted to grip a fastener. The extractor portion further defines an outside surface with a cutting edge is adapted to cut a bore when the tool grips and removes a fastener. The fastener removing tool further includes a main body fixed relative to the extractor portion. The main body is adapted to engage with a driving tool for powering rotation of the fastener removing tool. The fastener removing tool also includes a cutter portion fixed relative to the main body opposite the extractor portion. The cutter portion includes a plurality of cutting members defining a plug forming space therebetween. A formed plug is to be placed into the bore formed during extraction of the fastener.

Abstract: A bit for removing a broken fastener comprises a tip from which extend two or more notches separated by traction or biting surfaces formed from two-sided frusto-conically-shaped regions. The surfaces are bounded on one side by a nonlinear cutting edge and on the other side by a non-cutting edge and are configured to cut into the fastener when the bit is rotated in a direction opposite to the fastener's direction of engagement. Specific embodiments include configurations where the cutting edges extend at different angles with respect to the bit axis, where the biting surfaces comprise a plurality of serrations, and where the cutting edges are separated by flutes which spiral along a longitudinally extending periphery of the bit.

Abstract: A device 100 to extract a fastener 102 from a workpiece 104 wherein the fastener 102 has a predetermined direction of engagement with the workpiece 104, includes a shaft 106 having first and second end portions 108 and 110, cutting end tool 112 adapted to engage and bore into the fastener 102 as the shaft 106 is rotated, a drill bit portion 114 proximal to the cutting end tool 112 and adapted to engage and bore into the fastener 102, and cutting threads 116 that penetrate the fastener 102 a predetermined distance while the drill bit portion 114 bores into the fastener 102 at a relatively “slow” speed, whereby the cutting threads 116 secure the shaft 106 to the fastener 102 and promote the rotation of the fastener 102 contrary to the fastener's 102 direction of rotational insertion into the workpiece to ultimately remove the fastener 102 from the workpiece 104.

Abstract: A fastener removing tool is provided. The fastener removing tool includes an extractor portion having an inside surface adapted to grip a fastener. The extractor portion further defines an outside surface with a cutting edge is adapted to cut a bore when the tool grips and removes a fastener. The fastener removing tool further includes a main body fixed relative to the extractor portion. The main body is adapted to engage with a driving tool for powering rotation of the fastener removing tool. The fastener removing tool also includes a cutter portion fixed relative to the main body opposite the extractor portion. The cutter portion includes a plurality of cutting members defining a plug forming space therebetween. A formed plug is to be placed into the bore formed during extraction of the fastener.

Abstract: A wheel stud installing and removing system includes a C-frame; a forcing screw configured to communicate with the C-frame to move laterally through the C-frame; a swivel mounted on an end on the forcing screw; an adapter receiver mounted on an opposite end of the C-frame from the forcing screw, and configured to receive at least one of either a stud installing adapter and a stud removing adapter. A method of moving a stud includes: inserting one of either an installing adapter or a removing adapter into an adapter receiver on a C-frame; aligning a longitudinal axis of the adapter with a longitudinal axis of the stud; aligning the longitudinal axis of the stud with a longitudinal axis of a forcing screw; and turning the forcing screw.

Abstract: A bit for removing damaged screws is provided with a plurality of scraping grooves formed on the relief surface and wind around the axis of the bit. The scraping grooves allow the scraping edge to work as a non-planar scraping edge with concaves and convexes (increasing the scraping area and producing a plurality of sharp protrusions), which makes it easier for the bit to engage in the slot of a damaged screw and to get a good purchase and leverage on the damaged screw for removing a damaged screw easily. The scraping grooves also allow the front end of the bit to produce different working diameters that permits the bit to be engaged in the slot of differently sized screws.

Abstract: The method of making a tool for removal of broken screws from a base material, including the material of the bone of a medical patient. One end of the tool has an open bore with interior, left-hand tapered screw threads formed thereon by compressing the tool to form the taper after the threads are formed and presented in a cylindrical shape. The other end of the tool is solid for accommodating a driving tool which rotates the tool in the removal of the broken screw.

Abstract: A hexagonal driving tool includes a socket having a reception hole and the socket is connected with a hand tool. A hexagonal driving rod has a first end inserted in the reception hole and a groove is defined longitudinally in the hexagonal driving rod. A recess is defined transversely in the hexagonal driving rod and communicates with the groove. An elongate pawl piece is received in the groove and a first spring is located between the pawl piece and an inner surface of the recess. The first spring pushes one of two sides of the pawl piece out from the groove so as to be engaged with a rounded corner of a rounded hexagonal recess in the head of a bolt or screw.

Abstract: A fastener impact driver device includes a fastener engagement member having a plurality of projections disposed about a lower portion that engages a corresponding peripheral portion of a fastener. The device further includes a positioning member having an upper portion that ultimately receives a force thereupon, and a lower portion that engages a cooperating upper portion of the fastener engagement member whereby a force such a hammer strike is imparted upon the upper portion of the positioning member to drive the projections of the fastener engagement member into the head of the fastener without damage of the fastener engagement member, whereupon the positioning member is removed from the fastener engagement member and a hand tool is removably secured to the fastener engagement member to impart rotary motion to the member and the fastener thereby removing the fastener from or urging the fastener into a workpiece.

Abstract: A bit for removing a broken fastener comprises a tip from which extend two or more notches separated by scraping surfaces formed from two-sided frusto-conically-shaped regions. The scraping surfaces are bounded on one side by a cutting edge and on the other side by a non-cutting edge and are configured to cut into the fastener when the bit is rotated in a direction opposite to the fastener's direction of engagement. Specific embodiments include configurations where the cutting edges extend at different angles with respect to the bit axis and where the scraping surfaces comprise a plurality of serrations.

Abstract: A fastener extractor and a method of extracting a fastener are provided. The fastener extractor includes a shaft, an engagement end at a distal end of the shaft and an attachment end at a proximal end of the shaft. The engagement end includes a plurality of helical ridges and grooves. The attachment end extends axially from the shaft and includes a hexagonal cross-sectional portion adapted to engage an extraction tool. Adjacent ones of the plurality of the grooves form the ridges therebetween and the plurality of ridges is adapted to engage a pre-formed opening in a fastener to be removed.

Abstract: A combination ratchet wrench having a standard open-type or box-type wrench at one end thereof and a ratcheting extraction box at the other end thereof. The ratchet extraction wrench box is connected by a ratcheting mechanism to the wrench that allows rotation of the ratchet extraction wrench box relative to the wrench only in one direction. The ratchet extraction wrench box is provided with a fastener extraction head that has an interior bore extending inwardly from a receiving end. The bore has a plurality of helically-shaped grooves, each extending from the receiving end and curve radially and inwardly towards the central axis of the bore to form sharp ridges that extend in a helical fashion inside the bore. When the fastener extraction is placed over a fastener head, the ridges “bite” into the material of the fastener. Because the extraction head is formed as an integral part of the wrench there is no need to have a separate turning tool.

Abstract: Apparatus and methods for extraction of nails, screws and other such fasteners from wood or other host materials are disclosed. One embodiment of the apparatus includes a shank adapted for application at a rotational drive source, a two-part engaging member at one end of the shank having a cavity extending thereinto for receiving therein a fastener to be extracted and openable to release the fastener after extraction. A cutting component is defined at a bottom edge of the engaging member adjacent to an opening to the cavity for cleanly removing host material from around the fastener. A gripping surface formation comprising a spiraling striation is formed at a surface of the cavity for threadably engaging the fastener to be removed.

Abstract: The present invention is directed to a tool assembly for improving the insertion of threaded studs into confined spaces. The tool assembly includes a shaft having a bearing surface and defining an opening that is spaced apart from the bearing surface. The tool assembly also includes a sleeve having a threaded inside surface portion and a non-threaded inside surface portion, the non-threaded inside surface portion defining an opening, the sleeve mounted to the shaft with the sleeve opening aligned with the shaft opening. The tool assembly further includes a stop member positioned in the shaft opening and sleeve opening.

Abstract: A fastener impact driver device 10 includes a fastener engagement member 12 having a plurality of projections 14 disposed about a lower portion 16 that engages a corresponding peripheral portion 18 of a fastener 20. The device 10 further includes a positioning member 22 having an upper portion 24 that ultimately receives a force thereupon, and a lower portion 26 that engages a cooperating upper portion 28 of the fastener engagement member 12 whereby a force such a hammer strike is imparted upon the upper portion 24 of the positioning member 22 to drive the projections 14 of the fastener engagement member 12 into the head 44 of the fastener 20 without damage of the fastener engagement member 12, whereupon the positioning member 22 is removed from the fastener engagement member 12 and a hand tool is removably secured to the fastener engagement member 12 to impart rotary motion to the member 12 and the fastener 20 thereby removing the fastener 20 from or urging the fastener 20 into a workpiece.

Abstract: The present invention relates to a bit for removing damaged screws, the bit of the present invention is able to reach and engage the deep portion of the slot of the damaged screws, while the conventional bit is unable to do so, so as to remove the damaged screw. The bit is designed to have a sharp tip which can engage the deep portion of the slot of the damaged screw, so as to get a good purchase and leverage on the damaged screw to remove it easily.

Abstract: A bit for removing a broken fastener comprises a tip from which extend two or more notches separated by scraping surfaces formed from two-sided frusto-conically-shaped regions. The scraping surfaces are bounded on one side by a cutting edge and on the other side by a non-cutting edge and are configured to cut into the fastener when the bit is rotated in a direction opposite to the fastener's direction of engagement. Specific embodiments include configurations where the cutting edges extend at different angles with respect to the bit axis and where the scraping surfaces comprise a plurality of serrations.

Abstract: A pin removal and placement tool (50) has a body member (52) made of plate steel having a contact surface (52b) and a rear edge (52c). Tool (50) also may have an anvil plate (54) mounted on a striking plate (56), a drive shaft (58), and a handle (70) projecting at a right angle from the body member (52). The striking plate (56) is fixedly mounted to the rear edge (52c) and anvil plate (54) is disposed at a selected angle to the drive shaft (58) to enhance the striking force of drive shaft (58) and to reduce the length of the tool (50) so as to facilitate its insertion between the teeth of buckets, etc. A shoe (62) may be mounted on tool (5) to adjust the clearance between contact surface (52b) and drive shaft (58). The handle (70) may be either removably or fixedly attached to the body member (52) and be dimensioned and mounted to selectively project from a selected side thereof, or from both sides thereof.

Abstract: A fastener extractor is provided that includes an attachment end having an attachment means for connection to an extraction tool and a receiving end. The receiving end has an interior bore that angles inwardly towards the attachment end. The interior bore has a central axis and includes at least two arcuate grooves that extend along the interior bore towards the attachment end. The arcuate grooves curve radially and inwardly towards the central axis of the interior bore, with adjacent arcuate grooves forming sharp helically shaped ridges. A transition area is positioned between the attachment end and the receiving end and has a plurality of arcuate surfaces. Each of the plurality of surfaces corresponds to each of the arcuate grooves and projects inwardly from the corresponding groove towards the central axis. The interior bore is engageable over a fastener to be extracted.

Abstract: Apparatus for extraction of nails, screws and other such fasteners from wood or other host materials are disclosed. One embodiment of the apparatus includes a shank adapted for application at a rotational drive source, a two-part engaging member at one end of the shank having a cavity extending thereinto for receiving therein a fastener to be extracted and openable to release the fastener after extraction. A cutting component is defined at a bottom edge of the engaging member adjacent to an opening to the cavity for cleanly removing host material from around the fastener. A gripping surface formation comprising a spiraling striation is formed at a surface of the cavity for threadably engaging the fastener to be removed.

Abstract: A device for the extraction of broken fastener comprises a left handed cutting tool juxtaposed to a left handed drill bit that is surrounded by a socket. In a specific embodiment the socket has longitudinal slits, a ribbed inner surface, and a threaded outside surface adapted to be received by a collar.

Abstract: A method for manufacturing a socket tool includes: forging a socket blank to form a plurality of arcuate locking grooves; hydraulic working to form a plurality of helical arcuate locking grooves in the socket blank; turning and cutting the periphery of the socket blank to make the periphery of the socket blank smooth; performing a heat treatment on the socket blank; and forming a socket tool having a plurality of helical arcuate locking grooves which are extended and contracted from an outer end to an inner end of the socket tool to form a contracted conical hole. Thus, the socket tool can be used to forcibly rotate and detach a hexagonal screw member having worn or rust corners.

Abstract: A method for manufacturing a socket tool includes: forging a socket blank to form a plurality of arcuate locking grooves; hydraulic working to form a plurality of helical arcuate locking grooves in the socket blank; turning and cutting the periphery of the socket blank to make the periphery of the socket blank smooth; performing a heat treatment on the socket blank; and forming a socket tool having a plurality of helical arcuate locking grooves which are extended and contracted from an outer end to an inner end of the socket tool to form a contracted conical hole. Thus, the socket tool can be used to forcibly rotate and detach a hexagonal screw member having worn or rust corners.

Abstract: A bit for removing a broken fastener comprises a tip from which extend two or more notches separated by scraping surfaces formed from two-sided frusto-conically-shaped regions. The scraping surfaces are bounded on one side by a cutting edge and on the other side by a non-cutting edge and are configured to cut into the fastener when the bit is rotated in a direction opposite to the fastener's direction of engagement. Specific embodiments include configurations where the cutting edges extend at different angles with respect to the bit axis and where the scraping surfaces comprise a plurality of serrations.

Abstract: The invention concerns a tool for removing fastening members, such as nuts and studs. The tool comprises an elongate body member (30) with first and second ends, the first end having means (31′) for deforming an end face of the fastening member to provide an area of purchase thereon; and means (44) to cause rotation of the fastening member to unscrew the fastening member from the structure. Also within the scope of the present invention is a locating means (38′) for locating the first end of the body member (30′) with respect to the end face of the fastening member as well as a method for enabling removal of fastening members by action upon an end face of a fastening member.

Abstract: A set of tools for installation and a set of tools for removal of studs from a work piece are disclosed. The installation tools include body member with a removable bearing that can be set against the head of a stud that is to be installed in a workpeice. The stud removal tools include a pair of body members which are each mounted on the stud to be removed and tightened against one another so that one of the body members may be rotated to effect removal of a stud.

Abstract: A setting tool for facilitating the insertion of threaded rod anchors within a substrate or foundation comprises a substantially cup-shaped housing having an internally threaded bore for threadedly receiving and mating with an threaded rod anchor. A button member extends axially inwardly from an internal end portion of the cup-shaped housing and comprises a planar engagement surface for engaging the free end portion of the threaded rod anchor in a non-destructive manner, wherein the free end portion of the threaded rod anchor may have a planar or non-planar surface. An annular notch is also defined within an outer peripheral surface portion of the housing so as to define a line of frangibility along which the cup-shaped housing can be separated into a residual portion, which may be discarded after the threaded rod anchor is fixed within the foundation or substrate, and a nut member which remains threaded upon the threaded rod anchor for securing auxiliary components to the substrate or foundation.

Abstract: An extraction tool (20) for extracting spiral threaded inserts comprises an elongated basic body (23, . . . ,26), on the one end of which an extracting tip (28) narrowing toward the front and intended for being inserted with a cutting action into the threaded insert to be extracted is provided and on the other end of which means (23) for turning the extraction tool (20) about the tool longitudinal axis are provided.

Abstract: A device for the extraction of broken fastener comprises a left handed cutting tool juxtaposed to a left handed drill bit that is surrounded by a socket. In a specific embodiment the socket has longitudinal slits, a ribbed inner surface, and a threaded outside surface adapted to be received by a collar.

Abstract: A double-ended hexagonal shank tool bit for extracting Phillips head or similar screws with damaged heads. One end of the tool shapes the screw head recess to a flared opening. The other end of the tool is tapered with left-hand screw threads and diametrically opposite longitudinal gashes arranged to enable the tool to engage the sides of the shaped recess and remove the screw.

Abstract: A security fastener removing kit for removing security fasteners designed for only turning in a clockwise or tightening direction. The security fastener removing kit includes boring at least one hole in a head of a security fastener. A tool member is provided that has at least one tine that is removably insertable in the hole in the head of the security fastener. The tool member permits a user to rotate the head of the security fastener in at least a counterclockwise direction thereby unfastening the security fastener.

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 tool for removing threaded members, such as fasteners, damaged by corrosion or mechanical stress. The tool includes a first end and a second end opposite the first end. A generally annular body extends between the first and second ends and includes an inner wall. A drive engaging portion is positioned intermediate the first and second ends and is adapted for cooperating with a drive mechanism. A series of spiral flutes is formed along the inner wall of the annular body so as to provide a corresponding series of spiral crests extending along the inner wall. Proceeding from an end of the tool in a direction toward the drive engaging portion, the flutes and crests taper inward toward a central longitudinal axis extending through the annular body. When the tool is placed onto a fastener, the crests bite into an outer surface of the fastener to engage the fastener, thereby facilitating application of torque to the fastener to facilitate its removal.

Abstract: A tool for removing threaded members, such as fasteners, damaged by corrosion or mechanical stress. The tool includes a first end and a second end opposite the first end. A generally annular body extends between the first and second ends and includes an inner wall. A drive engaging portion is positioned intermediate the first and second ends and is adapted for cooperating with a drive mechanism. A series of spiral flutes is formed along the inner wall of the annular body so as to provide a corresponding series of spiral crests extending along the inner wall. Proceeding from an end of the tool in a direction toward the drive engaging portion, the flutes and crests taper inward toward a central longitudinal axis extending through the annular body. When the tool is placed onto a fastener, the crests bite into an outer surface of the fastener to engage the fastener, thereby facilitating application of torque to the fastener to facilitate its removal.

Abstract: A Phillips head screw driver bit for being driven with a power tool, includes a shank having a working end for engaging with and for driving fasteners. The working end of the shank includes four slots for forming four blades each of which includes a cutter leading edge for drilling into objects, and for guiding the fasteners to be easily engaged into the objects without additional drilling tools. The cutter leading edges of the blades may engaged into the damaged or broken fasteners for forcedly removing the fasteners from the objects without additional extracting tools.

Abstract: A double-ended hexagonal shank tool bit for extracting Phillips head or similar screws with damaged heads. One end of the tool shapes the screw head recess to a flared opening. The other end of the tool is tapered with left-hand screw threads and diametrically opposite longitudinal gashes arranged to enable the tool to engage the sides of the shaped recess and remove the screw.

Abstract: A device and method for inserting rivets. The device and method allows for accurate, consistent installation of threaded blind rivets. The device comprises a rivet insert tool, a rivet insert shaft, and a sleeve through which the shaft passes. This provides significant accuracy to less accurate rivet inserting devices.

Abstract: An apparatus for removing helical thread inserts having a removal notch formed along a female thread surface. The apparatus can selectively extract helical thread inserts by selectively engaging the removal notch and actuating the end of the insert radially inward to prevent the end of the insert from engaging threads of the bore which it is disposed in. The apparatus includes a handle, a head attached to the handle, and a manually operable key. The head includes a bore formed therethrough having a central axis offset from central axis of the head, whereby the key is rotatably supported in the bore and includes an engaging lip for selectively engaging the removal notch of the insert and allowing for easier removal of the insert.

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.