Abstract: A method for mounting a wear plate and a knife base on a disc chipper's disc, and a disc chipper. The wear plate (6) rests against the knife base (4) via two counter surfaces (12), one of which forms in the wear plate (6) a groove in parallel to the knife (3) and the other forms in the knife base (4) a ridge which can be fitted into this groove. The tightening force of the fastening bolts (17, 18) of the wear plate (6) presses the knife base (4) against the disc (1) by means of the wear plate via these counter surfaces (12).

Abstract: A rator for a land clearing device or forestry shredder which comprises a plurality of anchors spaced apart, offset, and arranged on a horizontal cylinder. Cutting elements are mounted between adjacent anchors, the anchors arranged such that there are no gaps between the effective areas of the cutting elements as the rotator spins. The anchors can also be arranged so that at least one cutting element is located at or near the cutting element area at all times.

Abstract: An interchangeable chipper tool attachment for a hog allows a hog machine to operate as either a hog or a chipper. An operator of the hog machine can remove hammer tools used in the hog and replace them with the chipper attachment. The chipper attachment includes knife receiving area, a knife support receiving area, and a fastener portion for mounting the tool holder to rotor disks on the rotor assembly of the hog machine. A knife assembly, including a chipper knife, is coupled to the tool holder at the knife receiving area and points in the direction of rotation of the rotor. A knife support block supports the chipper knife and is coupled to the tool holder at the knife support receiving area, a lateral face of the tool holder adjacent to the knife receiving area. When mounted in an interleaved fashion between the rotor disks of the rotor assembly, the chipper knife rotates in a circular path and produces chips by cutting wood waste against an anvil on the hog.

Abstract: A stump grinding apparatus having a tooth which is automatically retained with respect to, and appropriately gauged from a pocket. The tooth includes an elongated shank portion having front and rear ends and a head portion integrally extending from the front end of the shank portion. In a preferred embodiment of the present invention, a pair of longitudinally spaced holes are formed through the shank portion adjacent its rear end. A pin may be inserted through one of the two holes formed through the shank portion, with the chosen hole being dependent upon whether the shape of the pocket being used is either entirely round or partially round with a straight rear edge. When the tooth is securely clamped to the stump grinding wheel via the pocket, the pin is positioned in abutting relation to the rear end of the pocket, thereby preventing the tooth from moving axially with respect to the pocket.

Abstract: A double-edged replaceable knife adapted for use with chip-cutting machines of various descriptions. The knife has a pair of spaced deflector portions projecting from the front side of the knife. Between the deflector portions is a channel used in properly locating the knife on a chip-cutting machine. The deflector portions are spaced at equal distances from respective cutting edges in the knife, and provide wear surfaces fronting the movement of chip material thereacross. The deflector portions also control the shape of chips cut by the machine mounting the knife.

Abstract: Wood wafers are produced by feeding logs to a rotary cutter head drum with the longitudinal axis of the logs disposed substantially parallel to the rotational axis of the drum. The drum mounts a plurality of wafer cutting head units arranged in a V-shaped pattern with the apex of the V trailing the base thereof and with the cutting blades defining the ends of the base positioned at the opposite ends of the operative length of the drum. Each wafer cutting blade having a cutting edge disposed substantially parallel to the axis of the drum and offset circumferentially and axially from an adjacent cutting blade so that the cut produced by a cutting blade overlaps the cut produced by the next adjacent preceding cutting blade.

Abstract: The invention is meant for a cant forming arrangement of the kind with at least two rotational chipping heads with a basic cut off conical form where they each have a basic conical main surface and a small end, whereby the chipping heads are arranged in pairs with the small ends turned opposing one another and equipped with replaceable knives which are arranged on the respective chipping head's main face with the purpose to surface a log on two opposing sides, through length feeding of a log between the chipping heads, while they are rotating, and that the wood which is removed is made directly to chips by the knives.

Abstract: A stump cutting tool assembly for a stump cutting apparatus having a rotatable cutting wheel includes at least one tool holder removably secured to the cutting wheel, at least one cutting tooth mounted circumferentially and removably to the at least tool holder, the at least one tool holder including a wheel portion extending circumferentially along the cutting wheel and a tool portion extending axially at an angle to a plane of the wheel portion, the tool portion having an aperture extending circumferentially therethrough and the at least one cutting tooth including a shank and an insert attached to the shank.

Abstract: A removable cutterhead insert for use in a helical cutterhead for an industrial woodworking machine, the helical cutterhead including a generally cylindrical portion, a plurality of circumferential, spaced grooves extending into the cutterhead body from the periphery of the cylindrical portion and adapted to receive the removable cutterhead inserts, and fasteners for removably securing the cutterhead inserts in the grooves; the cutterhead insert includes a mild steel insert body and two blade units; the insert body having raised portions having triangular pockets formed therein so as to have two inwardly-facing flat portions, a hole to receive the fasteners for removably securing the cutterhead insert in the grooves between the inwardly-facing flat portions and two bolt holes to secure the two blade units to the insert body; and the blade units are triangular with cut-off corners each including a blade edge and configured so as not to occlude the countersunk hole and to have the blades edges disposed to align

Abstract: A blade assembly for a shredding machine is presented which can be used in the method for replacing broken blades and when rebuilding the blade seat. The method includes milling the base support to reduce its height and redrilling the blade bolt holes. A new independent blade seat is then affixed by double-threaded bushings after which a new blade can then be bolted atop the blade seat.

Abstract: A rotary chipping head with multiple knife structures distributed about its periphery. Each knife structure includes an end-located chipping knife with a cutting edge movable in a plane disposed perpendicular to the axis of rotation of the chipping head. End-located facing knives are interspersed with the knife structures for producing a smooth face in the work being processed. Anvils preceding the facing knives produce compression in the work being processed. Detachable facing elements mount the facing knives and the anvils.

Abstract: The invention relates to a knife system for a machine used in wood chipping, a knife (10), a guide component (14) and a filler part (24) and method of exchanging knives. The system comprises at least one turnable or at least two exchangeable guide components (14), where at least two guiding surfaces are mutually at different distances from the guide component surface supported on the disc.

Abstract: A debarker arm for a debarking machine, comprised of a crescent shaped member, a debarker arm support, an outwardly forwardly extending flange, a debarker tip receptacle, and a debarker tip seated in said receptacle, the invention comprising said outwardly forwardly extending flange extending above and forwardly of said debarker tip in the direction of incoming logs.

Abstract: The object of the invention is an apparatus for clamping a chipper knife (1) to a rotatable chipper disc (4) or drum so that the back surface (6) of the knife (1) is supported against a knife clamp (2) with a knife spacer (3), and that the knife clamp (2) and knife spacer (3) are movable relative to each other by means of the clamping element (5). The knife clamp (2) is provided with supporting surfaces (11, 12) which the back surface (6) of the knife (1) is adapted to lean against by at least two spaced-apart surfaces (11', 12'). The knife spacer element (3) includes a supporting surface (13) which is adapted to subject a front surface (14) of the knife (1) to a force acting between said supporting surfaces (11, 12) of the knife clamp (2) for bending the knife (1) between said supporting surfaces (11, 12) of the knife clamp (2) towards the knife clamp (2) so as to generate a compression stress in the free section of a front surface (16) of the knife (1).

Abstract: An improved wood pulverizer is provided with a rotating disc studded with a plurality of curved tapered hammers. One or more anvils is secured to the pulverizer with the anvil having teeth and slots located adjacent the surface of the disc. The hammers of the rotating disc pass through the slots of the anvils as the disc rotates to tear and shard wood into bits and pieces for subsequent use or processing. The anvils of the present invention are formed with two or more useable surfaces so that the anvils can be removed, rotated, and replaced to present fresh cutting surfaces to the disc. Further, the anvils are formed by a series of bolted together anvil segments to allow replacement of only single segments in the event of damage.

Abstract: A debarking tooth of a debarking machine comprises a platform secured to an outer surface of a rotary member rotatably arranged in a wood container; a blade tip plate detachably attached to the platform; an arbitrary number of engage projections formed on one of the platform and the blade tip plate in a tapered shape so that a horizontal area of each engage projection becomes gradually smaller toward a distal end; an arbitrary number of engage recesses formed on the other one of the platform and the blade tip plate in a tapered shape so that a horizontal area of each engage recess becomes gradually smaller toward a bottom, the engage recesses being respectively engageable with the engage projections; and a fixing screw member driven toward the platform from the blade tip plate with the engage projections engaged with the engage recesses, thereby securely attaching the blade tip plate to the platform.

Abstract: A saw tooth for a circular saw for a feller including, in one embodiment, a square saw tooth head having a frusto-pyramidal shape to be mounted on a holder, and the saw tooth head includes seats for receiving inserts. The inserts are provided with cutting tips and cutting edges while a clamp nut retains the inserts against the tooth head. When the edges and tips are worn or damaged from impact, the inserts are first replaced. When the seat of the head is damaged, the tooth can be rotated.

Abstract: A rotor for a land clearing device or forestry shredder which comprises a plurality of anchors spaced apart, offset, and arranged on a horizontal cylinder. Cutting elements are mounted between adjacent anchors, the anchors arranged such that there are no gaps between the effective areas of the cutting elements as the rotator spins. The anchors can also be arranged so that at least one cutting element is located at or near the cutting element area at all times.

Abstract: A double claw stump cutting tooth having two cutting heads having cutting faces angled to slice into a stump with both heads adapted for simultaneously cutting or chipping a stump.

Abstract: A finishing blade having a radiused cutting edge for a chipper to produce a smooth finish on a surface of a log. The blades are mounted on the chipper such that a cut produced by one blade will be overlapped by a succeeding blade. The cutting edge of the finishing blade is radius ground to a slight curvature, The curvature of the cutting edge assures that the plane of cut produced by a first blade will be intersected by a succeeding blade.

Abstract: A cutting tooth for use in a stump cutting apparatus wherein the cutting tooth comprises a mounting base and a head portion which are integral with one another and are made of a one-piece metallic forging. The forging is preferably made from AMS 4140 steel and the cutting tooth further comprises a cutting tip, preferably of tungsten carbide, which is fixedly attached to the head portion of the tooth. The disclosed preferred embodiments include those in which the head portion is disposed in a substantially straight line relationship with the mounting base and those in which the head portion is curved relative to the mounting base.

Abstract: The disclosure herein describes a knife holder forming part of a timber shaping and chip cutting head; the holder defines a flat shaped body bent in an open V-shape to form two integrally joined portions, one of which provides a surface for mounting upon a rotatable core and the other serves to secure the chip cutting knife. The head is formed of a plurality of adjacently disposed knife holders radially mounted on the face of said rotatable core, said face being perpendicular to the axis of rotation. The knife is removably mounted upon the knife holder in a manner that the knife can be rotated so that more than one cutting edge may be used.

Abstract: A stump cutting apparatus which may be mounted on a watercraft such as a barge and includes a rotating cutting drum having multiple cutter blades and driven by at least one hydraulic motor mounted on a boom extending from the barge. In a preferred embodiment the boom is connected to a linkage arm and the rotating drum is rotatably mounted on a pair of cooperating mount plates fixedly spaced by a spacer plate and pivotally attached to the boom and linkage arm to facilitate adjustment of the rotating drum upwardly or downwardly with respect to the extending end of the boom, while maintaining the cutting drum and spacer plate in horizontally parallel relationship. A pair of arm hydraulic cylinders have their cylinder ends attached to mount brackets provided on the respective mount plates and the cylinder pistons connected to a stabilizing arm pivotally attached to the mount plates for stabilizing the cutter blade against a stump or tree during the cutting operation.

Abstract: A removable cutterhead insert for use in a helical cutterhead for an industrial woodworking machine, the helical cutterhead including a generally cylindrical portion, a plurality of circumferential, spaced grooves extending into the cutterhead body from the periphery of the cylindrical portion and adapted to receive the removable cutterhead inserts, and fasteners for removably securing the cutterhead inserts in the grooves; the cutterhead insert includes a mild steel insert body and two blade units; the insert body having raised portions having triangular pockets formed therein so as to have two inwardly-facing flat portions, a hole to receive the fasteners for removably securing the cutterhead insert in the grooves between the inwardly-facing flat portions and two bolt holes to secure the two blade units to the insert body; and the blade units are triangular with cut-off corners each including a blade edge and configured so as not to occlude the countersunk hole and to have the blades edges disposed to align

Abstract: In a cutting blade mounting arrangement for inserted blade cutting heads a mounting plate for supporting a cutting blade at one side thereof has at its opposite side a tooth structure for firm engagement with the cutting head and the cutting blade has ground bores receiving cylindrical fitting pins projecting from the one side of the support plate for accurately positioning the cutting blade on the support plate in axial as well as in radial direction with respect to the axis of the cutting head.

Abstract: To provide a reliable, yet resilient, seat for a cutter blade or knife (13) in a rotary milling body (11), the milling body is formed with a bore (21) which intersects the inner wall (19) of a recess (12) in the circumference of the milling body (11). A roll pin is inserted in the bore, retained therein, but projecting over the plane of the wall surface (19). The knife (13) is formed with a longitudinal groove (27), having opposite flat angled side walls (60), which fit around the projecting surface of the roll pin. A holding element (15), fitted into the recess, bears against knife and resiliently clamps it against the roll pin. Preferably, the holding element (15) and the knife (13) are formed with an interengaging projection (41) and recess (42) arrangement.

Abstract: A log-slabbing chipper having a chipper head that includes a power-driven rotor head and multiple double-edged knives distributed about the rotor head. A detachable wear plate for each knife extends in covering relation over a cutting edge in the knife that occupies an inoperative position. The wear plate establishes a proper depth of cut for the cutting edge of a knife that follows the wear plate.

Abstract: A blade holder for a chipper having a support that is configured to accommodate chip flow. The support is scoop shaped to provide a guide surface to guide the chips through the chipper while avoiding damaging impact. The chipper blades are in two parts and fitted together in end-to-end abutment and forming a bend at their juncture. One of the blade ends is grooved to receive an end edge of the other blade whereby the juncture is overlapped for added strength and to resist wood fibers being wedged into the juncture.

Abstract: An improved chipper knife system includes reversible chipper knives having formed integrally thereon nose structures comprising a leading component of a chip breaking system. A clamp plate surface follows the nose structure and, by virtue of the nose structure taking wear, has extended life and, therefore, extended value. A simple clamp arrangement includes knife registration relative to a clamp plate and a calibration keeper bar establishes a fixed position between the clamp plate the knife holder. Knives are thereby dismounted and remounted relative to the clamp without an intermediate calibration step.

Abstract: A cutting tooth for use in a stump cutting apparatus wherein the cutting tooth comprises a mounting base and a head portion which are integral with one another and are made of a one-piece metallic forging. The forging is preferably made from AMS 4140 steel and the cutting tooth further comprises a cutting tip, preferably of tungsten carbide, which is fixedly attached to the head portion of the moth. The disclosed preferred embodiments include those in which the head portion is disposed in a substantially straight line relationship with the mounting base and those in which the head portion is curved relative to the mounting base.

Abstract: A disc hog for reducing timbers to wood chips and shards of a predetermined maximum size comprises a housing defining a disc-shaped interior cavity and a heavy metal disc disposed in the cavity and mounted for rapid rotation about its central axis. A feeder opening is formed in the housing and a chute is positioned to facilitate the feeding of timbers through the opening for presentation to the front surface of the rotating disc. Both the front surface and the rear surface of the rotating disc is studded with hammer blocks that protrude outwardly from the surface. The hammer blocks on the front surface are sized and configured to impact, tear apart, and shred a timber fed to the disc into wood chips and shards. The hammer blocks on the rear surface of the disc are sized and configured to reduce wood shards and chips to shards of smaller size.

Abstract: A chopper has a straight knife clamped between a clamping member and a counter knife. The knife, clamping member, and counter knife are collectively positioned in a machined area formed in a holder that is in turn fitted within a larger recess formed in a chopping disk. A first fastener secures the knife holder to the chopping disk, a second fastener secures the clamping member to the knife holder, and a third fastener secures the counter knife to the knife holder. A projection formed in the counter knife engages a groove formed in the knife to properly align the knife and to inhibit entry of fibers into the space between the counter knife and the knife. The holder further includes a series of steps that position the counter knife and the clamping member, respectively, with respect to the holder.

Abstract: An arcuate debarking tool for ring rotor debarking machines used in timber processing. The tool comprises an elongated, arcuate body having an outer end that removably mounts a cutting element, and an inner arbored end adapted to be coupled through a mandrel shaft or the like to a ring rotor. A curved, thread-like leading edge first contacts logs that are transmitted axially through the revolving apparatus, and deflects the tools radially outwardly until the log is surrounded by the revolving ring of debarking tools. A companion, spaced apart exit edge is angularly defined in the frame. It functions in a thread-like manner to slowly unengage the rotating tools from the longitudinally traveling, debarked log. The curved exiting edge threadably revolves about the log circumference and slowly transfers the only remaining contact point between the withdrawing log and the revolving tool to an inward position whereby the tool is slowly, rather than suddenly, allowed to radially retract.

Abstract: The invention relates to a cutter block and a knife for chippers for removing particles of wood, which are used for producing particle board and the like. The knife is embodied as a disposable discontinuous or multiple edge knife or as a solid blade knife. The knife has retention and guiding recesses engaged form-fittingly by positioning pins of a support plate. Further, the knife is in compressive contact with a side wall face, trailing in the direction of rotation of the cutter block of the recess in the surface region of the block body.

Abstract: A knife (12) are a holding and releasing mechanism (8) are oriented in the direction of a radius of a chipper disc (19). The holding and releasing mechanism (8) is pushed in the direction of the radius of the chipper disc to release the knife (12) and drawn in the opposite direction to fasten the knife in the chipper disc (19). The time consumed in replacing the knives is reduced and laborious manual operations can be avoided. The procedure can be automated.

Abstract: A log-slabbing chipper with multiple knife structures distributed about the periphery of a power-driven rotor head. Each knife structure includes a holder and a pair of assemblies mounting double-edge replaceable knives. Each knife is mounted between a clamp and a fixed counterknife. Each knife has a serrated back-bearing surface and each clamp has a correspondingly serrated clamping surface. Adjusting screws exert pressure on the clamps to slide the clamps and the knives with respect to the stationary counterknives to achieve desired precise edge positions.

Abstract: A stump grinder having a support frame, an elongated main beam horizontally pivotally mounted on the frame, and a cutter wheel supported by and transversely oriented with respect to the main beam and rotatable about a substantially horizontal axis, the cutter wheel having a plurality of peripherally mounted stump cutter teeth spaced apart circumferentially and axially in a predetermined transversely oriented cutting pattern. The stump grinder is attachable to a three-point hitch of a tractor and the cutter wheel is directly driven by the tractor power take-off. Multiple stabilizers are mounted on the frame to provide stability as well as cutting depth control. Compensation utilizing multiple universal joints is provided to minimize angular velocity differences between the tractor power take-off and the cutter wheel. Depth gauging is provided on the periphery of the cutter wheel to control the depth of cut of individual teeth.

Abstract: A bit with a fiber cutter for a rosser head debarking machine. The bit has a base for mounting the bit onto the rosser head. The striking edge of the bit is connected to the base and comes into contact with bark and removes the bark as the rosser head spins. The bit has at least one replaceable fiber cutter that includes a cutting edge that cuts through the bark or fiber within the bark as the rosser head spins. Preferably, the fiber cutter is disk-shaped and tapered away from the striking edge and cuts through the fiber in the bark in a perpendicular direction to the fiber. The cutter can be connected to the bit by a threaded bolt that is positioned through a hole in the middle of the cutter and into a threaded hole in the bit. The bit can have threaded holes on both sides to allow two cutters to be installed or for the bit to be rotated.

Abstract: A chipper apparatus including a rotating disc with one or more knife assemblies mounted on the disc operable to produce wood chips under the cutting action of the knives. Each knife comprises an elongate knife body bounded by opposed cutting edges. The cutting edge further includes a contact surface for breaking apart and deflecting chips. The knife assembly includes interlocking keys for adjustable positioning of the knife in relation to a counter knife having multiple key recesses. The adjustable positioning of the knife permits the complete resharpening of the knife cutting edges.

Abstract: The present invention includes a rotatable cutting head assembly (12), such as for a planer or a jointer, which planes a work surface on a workpiece (22). The cutting head assembly (12) comprises a rotatable elongate support block (30), a pair of blades (32), and a pair of elongate retainers (34). Each blade (32) has a straight elongate cutting edge (50,51) which extends parallel to and is spaced radially from the longitudinal axis (36) of the support block (30). Each retainer (34) is attachable to the support block (30) to clamp a respective blade (32) therebetween. Retainers (34), blades (32) and support block (30) have cooperating alignment ribs (64) and elongate slots (52). The slots (52) extend parallel to the longitudinal axis of the support block.

Abstract: A stump-grinding apparatus includes a primer mover secured to a frame having a pair of wheels and a handle. A cutting wheel is secured to the prime mover for rotation. At least one cam member is coupled between the wheels and the frame and is operable from the handle to selectively adjust the height between the cutting wheel and the object to be disintegrated. A throttle member is also secured to the handle for selective control of the prime mover. The cutting wheel has a generally disk-shaped element having an outer diameter. At least one cutting tooth having a leading cutting edge and a generally opposite trailing cutting edge is secured to the outer diameter of the disk to define a selected angle between the leading cutting edge and a line parallel to the axis rotation of the cutting wheel. This angular offset permits the cutting wheel to cut a wider kerf, and to impart a slicing action in addition to the chipping action of the teeth.

Abstract: A saw blade disc for a tree felling head has tooth holders about its periphery which support cutting teeth asymmetrically above an inner plate of the disc.

Abstract: A rotary cutter grinder that cuts and grinds upon its circumferential surface is well suited for stump grinding and the like applications. The rotary cutter grinder is constituted by a hub portion for mounting to the power output shaft of a prime mover and plural arms unitary with the hub portion. These arms are substantially uniformly spaced about the hub portion and extend radially outwardly therefrom. A cutting tool, usually a tungsten carbide cutting tool, is mounted to each of the arms at a positive rake angle relative to the perpendicular to the direction of motion by the cutting tool.

Abstract: A hand-operated planer has a rotating blade holder having a base body, at least one planing blade and a pressing plate which presses the at least one planing blade against the base body, the pressing plate having one side which presses the planing blade against the base body and another side which is formed differently from the one side so that when the pressing plate is reversed the another side can press another planing blade which is different from the planing blade against the base body.

Abstract: In one embodiment of saw tooth assembly, the tubular saw tooth is releasably inserted with friction fit inside the hollow of a tubular mount. In an alternate embodiment, it is the tubular mount which is releasably inserted with friction fit inside the hollow of the tubular tooth. In both cases, the hollows of the mount and tooth are coextensive, whereby a common axial through-channel is defined. The tubular mount is to be anchored to the peripheral edge of a circular saw discoid plate. The wood chip generated during circular saw operation can therefore freely engage through the common through-channel, i.e. through the whole saw tooth assembly, and escape therefrom. Wood chip clogging of the saw tooth during sawing operations is therefore substantially prevented, and the aerodynamic features of the circular are accordingly enhanced.

Abstract: A chipper employs a rotary cutting disk with a plurality of radial knife assemblies. Each knife assembly has a reversible blade of generally trapezoidal cross section. The assembly has a knife holder and a knife clamp that sandwich the blade between them. An elongated load bar is seated in a recess in the clamp and supports a sloping surface at a concealed edge of the blade.

Abstract: A cutting blade for working logs to timber form while simultaneously removing wood chips which includes a pair of adjacent recesses formed in the periphery of the blade. A knife is bolted in the cutting blade in a first recess and a wear insert is separately bolted to the cutting blade in the adjacent recess. The bolts are countersunk so as not to extend outwardly from the knife or wear insert.

Abstract: A chipping cutter head including a double-edged knife and support structure mounting the knife in a pocket provided at the periphery of a cutter head body. The support structure includes a block member fastened by screws to the floor of the pocket. Adjustment structure is provided for adjusting the position of the block member, with this being effective to shift the position of the cutting edge of a knife supported on the block member. A replaceable insert member with a wear surface is positioned by a pin on the block member, and this insert member supports the knife and the knife is locked from shifting axially on the insert member.

Abstract: An improved bracket clamps a cutting tool to the wheel of a stump cutting apparatus and includes a channel defined between a leading bracket half and a trailing bracket half. The trailing bracket half includes an extension extending outwardly beyond an outermost edge of the leading bracket half. The channel encloses at least two-thirds of the cutting tool, and the extension has a planar surface in engagement with the surface of the cutting tool proximate to the cutting tip when the other end of the cutting tool is aligned with the opposing end of the channel. The extension provides rearward support for the cutting tip.

Abstract: A knife assembly for a disc type wood chipper includes a reversible disposable knife having a serrated back bearing surface positioned between a serrated knife clamp and a flat counterknife. The knife can be reground and advanced along the serrated clamping surface of the clamp so as to maintain a desired edge position with respect to the surface of the chipper disc and the anvil surface.