Abstract: A band saw blade comprising a plurality of teeth, wherein each tooth comprises a tip; a rake face formed on one side of the tip; a primary clearance surface formed on an opposite side of the tip relative to the rake face; a secondary clearance surface formed on an opposite side of the primary clearance surface relative to the tip; and a gullet located on an opposite side of the rake face relative to the tip and defining a depth (D) between a base surface of the gullet and the tip. Each tooth further defines a first gullet radius (R1) located between the gullet and the secondary clearance surface; a second gullet radius (R2) extending between a base surface of the gullet and the rake face; and a pitch (P) between the respective tooth and a preceding tooth. In each tooth, R2>D>RQ, and D/P is between about 25% and 35%.

Abstract: An apparatus for cutting materials and more specifically an improved saw blade includes a plurality of variable teeth thereon. The variable tooth saw blade cuts faster and smoother while reducing harmonic vibrations. Specifically, the teeth on the saw blade are grouped into sections with differing circumferential widths and differing spacing between the sections.

Abstract: A metal cutting band saw blade has a plurality of cutting teeth defining a cutting direction, and a repeating tooth pattern of between 3 and 7 teeth. Each tooth defines a laterally-extending upper surface having a width and a height with respect to the back edge of the blade, and side surfaces extending laterally and downwardly on opposite sides of the upper surface relative to each other at acute angles relative to the upper surface. The teeth located rearwardly of the first tooth with respect to the cutting direction of the saw blade define progressively lower heights and progressively smaller acute angles of the side surfaces, and the widths of the upper surfaces of these teeth are greater than the width of the upper surface of the respective first tooth.

Abstract: A saw blade for power tools, in particular for power reciprocating saws, includes a blade back (11) and a toothing (12) extending along the lower edge of the blade back and having many saw teeth (13) lined up in succession, In order to increase the blade life and service life of the saw blade, especially in a Thick, stable embodiment, the saw teeth (13) in successive portions (a, b) of the toothing (12) have the same tooth width (az, bz), which, however, differs from that of the saw teeth (13) in the preceding or the succeeding portion (b, a) of the toothing (12).

Abstract: An apparatus for cutting materials and more specifically an improved saw blade includes a plurality of variable teeth thereon. The variable tooth saw blade cuts faster and smoother while reducing harmonic vibrations. Specifically, the teeth on the saw blade are grouped into sections with differing circumferential widths and differing spacing between the sections.

Abstract: The present invention provides a cutting strip (102) which includes a flat, strip member (201) adapted to be attached to the edge of a carton. The member (201) having a first edge (202) having a plurality of teeth (204). The plurality of teeth (204) having a non-uniform tooth pattern (205) which comprises a first tooth pattern along a first section (209) of the edge and a second tooth pattern (207) along a second section (210) of the edge so that a sheet-tearing force can be applied to a sheet on either the first end or the second end of the member (201).

Abstract: A saw blade which has an unset tooth and left and right set teeth which are set to a right-and-left direction that, when a thickness of a body section of the saw blade is D and a set width is T, a relationship that T=D+2&agr;; when the thickness D of the body section and the coefficient &agr; establish a relationship that 0.85≦D≦0.95; 0.15≦&agr;≦0.35. In addition, when 0.96<D≦1.2, 0.2≦&agr;≦0.4 is established; when 1.2<D≦1.5. 0.25≦&agr;≦0.43 is established; when 1.5<D≦1.7, 0.3≦&agr;≦0.5 is established; and when 1.7<D, 0.35≦&agr;≦0.6 is established.

Abstract: Provided with a film cutter that has a guiding mechanism in accordance with the present invention includes a housing providing a pair of guiding rails thereon. The housing is adapted to be mounted on a box containing a film roll. The housing includes at least a receiving slot arranged adjacent to the guiding mils. At least a film positioning element is arranged in the receiving slot for providing a robust positioning of the film spans thereover and a cutter assembly moveably supported by the guiding rails for separating the film spans over the rails. When the film from the film roll is tightly stretched by the film-positioning elements thereby providing a clean cut when the cutter assembly slides over the stretched film.

Abstract: A saw blade includes a base body and a plurality of groups of saw teeth. Each group of saw teeth is provided with a first section and a second section, wherein the first and second sections are adjacently positioned and respectively include a plurality of pre-cutting saw teeth, each of which has a first clearance angle, and re-cutting saw teeth, each of which has a second clearance angle. The pitch between each two saw teeth is the same with the others, but the first clearance angle of the pre-cutting saw teeth and the second clearance angle of the re-cutting saw teeth are different from each other.

Abstract: A saw tooth for a circular saw for a feller includes, in one embodiment, a square saw tooth body having a multi-faceted shape to be mounted on a holder and for receiving inserts fastened to inwardly sloping seating surfaces on the cutting end of the tooth body. The inserts are provided with cutting tips and cutting edges to form angled cutting edges about the entire periphery of the cutting end of the tooth body. Notches are made in the seating surfaces and inserts in order to permit adjacent inserts to overlap one another, such that the angled cutting edges are strengthened at their junctions, thereby reducing damage of the inserts and improving the cutting performance of the saw tooth.

Abstract: A side cutting edge of a tip 20 fixed to the outer circumference of a circular saw blade body 11 has a inflexion point K at a portion at which the tip projects laterally to the greatest distance. An outer-circumferential-side portion of the side cutting edge has a negative radial clearance angle of not less than −1° but less than 0° at the inflexion point, and an inner-circumferential-side portion of the side cutting edge has a positive radial clearance angle of greater than 0° but less than −1° at the inflexion point. By virtue of this configuration, a cut surface having a better surface roughness as compared to that obtained conventionally can be obtained in cutting of a soft material such as wood by use of a circular saw.

Abstract: A saw blade for a circular saw has a circular disk with a predetermined radius and a predetermined thickness. Teeth are arranged on the circumference of the circular disk and elongated air passages are provided in the substantially circular side faces of the circular disk. The saw blade has two parallel saw blades that are driven in coaxially opposite directions. In order to improve the operational behavior of the saw blade, especially in its thermal characteristics while providing a high mechanical stability, a respective longitude of the elongated air passages extends in a selected direction to lie in an area that extends from a first direction of a secant intersecting the side faces to a second direction of a circumferential arch in the side faces. The elongated air passages are located in an outer region defined by a ring area. The outer border of the ring area is provided by the circumference of an outer circle having a radius in the order of about 0.75 to 0.95 times the radius of the circular disk.

Abstract: A structural band saw blade is provided having a cutting edge defined by a plurality of teeth spaced relative to each other, and a back edge located on an opposite side of the blade relative to the cutting edge. Each tooth of the band saw blade defines a tip, a rake face formed on one side of the tip, a primary clearance surface formed on the opposite side of the tip relative to the rake face, a secondary clearance surface formed on the opposite side of the primary clearance surface relative to the tip, and a tertiary clearance surface formed on the opposite side of the secondary clearance surface relative to the first clearance surface. The primary clearance surface defines a first acute relief angle, the secondary clearance surface defines a second acute relief angle less than the first acute relief angle, and the tertiary clearance surface defines a tertiary acute relief angle greater than the first and second relief angles.

Abstract: A saw blade that includes a bandsaw body and a plurality of unset teeth having a generally uniform height. The teeth are disposed on the bandsaw body. At least some of the teeth have a cutting extension that extends above the uniform height of the teeth.

Abstract: The present invention contemplates a stump grinding wheel that provides a user of a stump grinder with visual access through the wheel. The wheel comprises first and second opposing surfaces joined by a common edge. The edge is shaped in the form of a polygon and includes several intermittently spaced apart gaps positioned between successively positioned extensions that protrude radially outwardly from the first and second surfaces. The wheel further comprises a first, conventional, centrally positioned hole formed through the first and second surfaces for coupling the wheel to a motor; a second set of holes for permitting cutting teeth to be mounted to the wheel; and a third set of holes formed through the first and second surfaces and positioned between the first hole and second set of holes. The third set of holes provides an additional window through which a user may visually inspect a stump while it is being machined.

Abstract: The present invention provides a band saw blade 1 which has less difference in cut areas of workpieces with small diameters and cut areas of workpieces with large diameters, and is capable of weakening the cutting resistance and preventing unintentional bending of a cutting line and noise generation when a workpiece, which cannot easily be cut, is cut. The band saw blade 1 has, on the back surface 5 of a body 3 thereof, a wavy back surface 5 which is changed periodically or irregularly. A plurality of imaginary curves L1,L2 running parallel to the wavy undulation provided for the back surface 5 are formed opposite to the back surface. Moreover, a plurality of saw teeth 2,4,6,8,10 having tooth tips which substantially describe the imaginary curves L1,L2 are formed. Thus, constant areas can be cut by the band saw blade 1 regardless of the diameter of the workpieces required to be cut. Moreover, the cutting resistance can be weakened, and unintentional bending and noise can be prevented.

Abstract: A reciprocating (saber) saw blade having normal cutting teeth for most of its working length from the tip towards the connection end.

Abstract: A cutting tool for separating and formatting of sheet materials has a rotationally driven support body having cutting teeth arranged about a circumference of the support body. The cutting teeth have a tooth profile with a radially outwardly positioned front-cutting area with a separating cutting edge and a formatting area with main cutting edges determining the cutting width of the cutting tool. The tooth profile further has a transition area located radially between the front-cutting area and the formatting area. The main cutting edges in the formatting area are arranged radially separately from the separating cutting edges of the front-cutting area by the transition area, wherein the transition area has transition cutting edges adjoining the cutting edges and angled relative to the separating cutting edges toward a radial center axis of the cutting tool. The front-cutting area is symmetrical relative to the radial center axis of the cutting tool.

Abstract: This invention gives saw blades multiple tiers of saw teeth. Each tier of teeth is designed for and dedicated to a particular cutting characteristic. The first tier to engage the material being cut has fast cutting characteristics. Each subsequent tier cuts away the kerf surfaces left by the preceeding tier and cuts a new smoother kerf.

Abstract: A method of preventing a tooth from continuously breaking in a band saw blade, comprises the steps of: moving the band saw blade to a longitudinal direction and moving the band saw blade to a cutting direction perpendicular to the moving direction of the band saw blade so as to cut a work; bringing a projecting portion disposed at a rear position of a surface of relief at the back of a tip in a saw tooth broken into contact with a bottom portion of a cutting groove in the work when the tooth breaking is generated in the saw tooth of the band saw blade; and limiting a cutting amount of the following saw tooth, thereby preventing the following saw tooth from breaking.

Abstract: A band saw blade includes a plurality of set teeth which are formed in a variable pitch. In that construction, a bending lengths of each of the set teeth at a setting and bending position or at a bendingly setting position are substantially equal to each other.

Abstract: A saw blade is disclosed which comprises a fixing receptacle for fixation on an oscillating drivable drive shaft, having a cutter that is distanced from the fixing receptacle, the cutter extending essentially tangentially or arch-shaped with respect to the fixing receptacle and being provided with a plurality of saw teeth. The cutter comprises at least a first section and a second section, and the saw teeth have at least in the area of one section another spacing or another set of saw teeth than in the other section. The saw blade allows a precise application to the object to be cut and a later continuation of the cutting process with increased feed.

Abstract: A saw blade has teeth which are located on a carrier blade. Saw teeth flanks are curved and convex. A transition point between a cutting edge of the saw tooth and the curved convex saw tooth flank is such that a spacing distance between a radial center of the saw tooth flank and a radial plane of symmetry of the saw tooth is greater than a spacing distance between the transition point and the plane of symmetry.

Abstract: The saw blade has a base body on which are mounted uncrossed teeth with cutting edges. The teeth are combined to form successive groups of at least three teeth and are disposed symmetrically to the longitudinal center plane of the base body. The teeth of one group increase in height from tooth to tooth while simultaneously decreasing in width.

Abstract: A band saw blade having relatively extended pitch patterns of eight of more teeth exhibits relatively low noise and vibration during cutting operations, and substantially uniform tooth loading characteristics. The band saw blade defines set patterns within each pitch pattern, and each set pattern is defined by an unset leading tooth followed by a plurality of offset trailing teeth. Each tooth within each set pattern defines a pitch between the respective tooth and the preceding tooth in the cutting direction of the saw blade, and an accumulated pitch between the respective tooth and the preceding tooth of like set direction in the cutting direction of the saw blade. The ratio of pitch to accumulated pitch for each tooth within each set pattern increases from one tooth to the next in the direction opposite the cutting direction of the saw blade for substantially uniformly distributing the chip load over the teeth of the saw blade.

Abstract: A metal cutting bandsaw blade includes a strip and a recurring group of teeth projecting therefrom. The recurring group of teeth has a setting pattern and a height pattern. The setting pattern has at least three units selected from the following setting types: (a) unset teeth (b) teeth set to the right (c) teeth set to the left. The setting pattern includes at least one of each of the setting types. The height pattern has at least two selected from the following height types: (a) high teeth (b) low teeth. The height pattern includes at least one of each of the height types. The total number of teeth in the recurring group is the product of the number of setting units and the number of heights units. The number of setting units is incommensurable with the number of height units. The number of teeth set to the right in the recurring group is equal to the number of teeth set to the left. All of the set teeth in the group have substantially equal setting widths.

Abstract: A metal saw for making long cuts through thick soft metals such as aluminum, copper or stainless steel, where friction, cutting force and scarring of the cut sides are minimized at a low production cost by grinding all teeth with a top edge inclined right or left 5 to 10 degrees, followed by setting some but not all teeth at a setting angle sized so that the top edges of the set teeth extend substantially at a right angle to a center plane of the body of the saw.

Abstract: A saw blade includes a body (1) being formed symmetrically about a longitudinal center plane (8). A plurality of spaced apart unset teeth is formed symmetrically along the longitudinal center plane of the body in at least one recurring cycle of teeth. The at least one recurring cycle of teeth includes at least one first group of teeth and at least one second group of teeth. The at least one first group of teeth includes at least two first teeth (2). The height of one first tooth (2) is different than the height of one other first tooth (2). The width of one first tooth (2) is different than the width of one other first tooth (2). The at least two first teeth (2) each include at least one effective cutting edge (5) having at least one phase (7). The at least one second group of teeth includes at least two second teeth (2*). The heights of the second teeth (2*) are approximately identical and the widths of the second teeth (2*) are approximately identical.

Abstract: The saw blade (30) for an oscillating saw machine has a row of M-shaped twin teeth (38) on its toothed edge (40). Each twin tooth has two tooth tips pointing in opposite directions so as to be effective for sawing in two opposite saw blade motion directions. Each twin tooth is alternately twisted about a central twist axis in one rotation direction or another opposite rotation direction out from the saw blade plane so that the tooth tips of each twisted twin tooth point in opposite directions out from the saw blade plane.

Abstract: A saw blade 1 comprises a preceding tooth 5 constructed by a straight tooth performing no saw setting operation in left-hand and right-hand directions and a succeeding tooth 7 for cutting a cutting groove formed by the above preceding tooth 5 to enlarge and open the cutting groove in width. The succeeding tooth 7 has left-hand and right-hand set teeth 7L, 7R bent in the left-hand and right-hand directions by splitting an approximately central portion 7D of a tooth edge on a tooth line in its thickness direction; and the clearance between end tip insides of the above left-hand and right-hand set teeth 7L, 7R is smaller than the thickness of the preceding tooth 5. Further, the thickness of portions of the left-hand and right-hand set teeth 7L, 7R near their end tip portions are approximately equal to the thickness of portions of the left-hand and right-hand set teeth near respective base portions thereof.

Abstract: A saw blade comprising a basic body (8) lying in a longitudinal center plane (9) and having an edge and including along its edge a group (6) of recurring teeth (1, 2, 3, . . . ), the group (6) comprising at least one unset leading tooth (1) being provided with a phase and having an effective cutting-edge section (10) and a preferably even number of trailing teeth (2, 3, . . . ). The leading tooth (1) has a larger height than all of the trailing teeth (2, 3, . . . ). All of the trailing teeth (2, 3, . . . ) have different plastic deformations at their tips (28) by displacements of material in the running direction (24) of the saw blade. Each of the trailing teeth (2, 3, . . . ) have both a positive enlarged rake angle (gamma.sub.2, gamma.sub.3, . . . ) and a reduced height (h.sub.2, h.sub.3, . . . ) with respect to the leading tooth (1) produced by different plastic deformations.

Abstract: A bandsaw blade includes recurring identical groups of teeth. Each tooth group consists of two to six teeth. Each group is spaced from leading and trailing groups by first and second respective distances. The first and second distances being different from one another.

Abstract: A reciprocating saw blade moved in opposite directions parallel to a longitudinal axis is formed with at least one row of longitudinally succeeding teeth having tips all lying on a common tip line parallel to the longitudinal axis and including even teeth all oriented in one direction parallel to the axis and odd teeth alternating with the even teeth and all oriented in the opposite direction parallel to the axis. Each even tooth forms with one of the adjacent odd teeth a double tooth and the tips of the teeth of each double tooth are set laterally of the blade to one side with the lateral set by an offset that alternates longitudinally from double tooth to double tooth to opposite sides of a center blade plane. The offset is the same for all teeth. Each tooth has a relatively steep leading edge and a relatively shallow trailing edge, relative of course to the respective longitudinal direction.

Abstract: A band saw blade or hacksaw characterized because of it is machined with two rows of a plurality of cutting teeth, sustained and projecting from the base itself of the laminar body of the blade, the saw presents a laminar body at one of its ends while at the other end there are teeth with different geometries according to the use for soft cuts or hard cuts along the edge of said body of the band saw, being said rows formed by a pair of teeth of the same geometrical sizes of inverted "V" shape, but being in turn projected at an angular direction according to the required number of teeth +10 degrees, which is equivalent to the desired angle toward the external part of its axis, one with regard to the other, and alternatively followed by only one straight tooth of the same depth and so on, successively.

Abstract: A signature perforating knife that is useable to perforate multi-layer signatures is formed as a compound knife using either several knife blades or a combination of knife blades and spacer blades. Each compound perforating knife has a uniform base thickness. The specific characteristics of the compound perforating knife can be adapted in accordance with the weight of the paper web being printed and the number of layers of the multi-layer signature which will be perforated and then folded in a folding apparatus of a web-fed rotary printing press.

Abstract: To provide a general-purpose saw blade which will saw different materials cost effectively, the saw blade includes a plurality of sets of teeth, each set including saw tooth having a large relief angle and a small tooth angle which provide fast cutting speeds, and with saw tooth having a small relief angle and a large tooth angle which provide the resistance to chipping.

Abstract: Multifunctional blade designs for rotational oscillating cutting include, in one aspect, different cutting teeth segments and cutting agent segments arranged along separate portions of a common cutting edge to carry out various cutting tasks. In another aspect, non-circular cutting blades have separate cutting edge segments, each segment having different cutting teeth or cutting agents. The blade edge may include one portion having grit bonded to the cutting edge to cut hard objects, and another portion having cutting teeth for cutting softer objects. Likewise, the blade edge may include two portions, each having cutting teeth of differing size and pitch to cut differing materials. Another embodiment comprises a triangular blade, the sides of the triangle provided with cutting grit bonded to the edges. Alternatively, at least one side of the triangle may include cutting teeth, so that each side of the triangle is adapted to cut different types of materials.

Abstract: A new blade, and a method of cutting therewith, having repeating sets of teeth, each set having sub-sets which differ from each other in at least one cutting characteristic including straight teeth, primary cutting teeth which are left-sided and right-sided and secondary cutting teeth which are left-sided and right-sided, said secondary cutting teeth having a large relief angle.

Abstract: A blade for a surgical saw has an elongate body with distal and proximal ends, and a plurality of teeth formed on an outwardly facing edge surface of the distal end. The spaces between adjacent teeth are defined by surfaces which lie in planes which are non-perpendicular to the substantially flat surfaces which define the body of the blade. These non-perpendicular surfaces guide cuttings generated by the teeth laterally toward the flat surfaces of the blade and outwardly toward the proximal end of the blade as the blade advances in a cut. Each of the teeth formed on the edge of the blade has a pointed form. Approximately half of the teeth lie in a row in which the respective points lie in a first cutting plane which extends in parallel with, and lies adjacent a first side of, a plane which extends longitudinally through the center of the blade body.

Abstract: A ring saw is described which has a novel construction for centering the cutting ring. The ring saw is characterized by a groove in the inner annular surface of the cutting ring. A plurality of rollers are provided which engage the groove in the inner annular surface. The rollers serve to center the cutting ring relative to the saw body while withstanding axial and radial loads placed upon the cutting ring. The construction, as described, serves to increase the capacity of the cutting ring to withstand radial and axial loading.

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 saw blade comprises scratcher teeth which are not set, and shaving teeth which are set. All of the teeth have their leading and trailing lateral edges chamfered. The chamfering of successive teeth occurs at alternate sides of the blade. The scratcher teeth have sharp points, whereas the shaving teeth are truncated to form oblique top surfaces and to render the shaving teeth shorter than the scratcher teeth.

Abstract: The thin kerf circular saw blade of the present invention is a high speed saw blade having a plurality of spaced teeth around its periphery. The blade contains a plurality of radial slots extending inwardly from the periphery of the blade. A combination of features including the aggressive hook angle of the teeth, a plurality of expansion slots, a shallow gullet, reinforcing shoulder, carbide cutting elements, and a thin profile provide a saw blade for cutting a thin kerf at a high cutting speed. A slick coating including friction reducing and non-stick compounds reduce resin buildup and further improve the speed of cut of the thin kerf saw blade.

Abstract: Saw blade for sawing metal, the saw blade having straight teeth as well as set teeth. The straight teeth extend higher than the set teeth and are chamfered on both sides such that the chamfers extend below the top edges of the set teeth. The set teeth have, on their outer side corners only, either no chamfer or a small chamfer.

Abstract: A cutting wheel for use in a stump-grinding apparatus that has a reversible disk having an outer diameter. The disk has a generally noncircular hole through the center thereof to register with a correspondingly generally noncircular shaft for transmission of torque and rotation from the shaft to the disk. At least one cutting tooth having a leading cutting edge and a trailing cutting edge is secured to the outer diameter of the disk. The reversible disk may be removed from the generally noncircular shaft and subsequently reversed and replaced on the shaft, wherein the trailing cutting edge is transposed with the leading cutting edge.

Abstract: A saw blade includes the: (1) provision of a trapezial tooth between every two triangular teeth, the trapezial tooth having two opposite sides which extend towards one another at a top end, a distal bottom end opposite the top end and two opposite trapezial faces; (2) provision of cutting edges by forming two inclined faces which converge from one of the trapezial faces towards the other one of the trapezial faces; (3) provision of a cut at a rear one of the inclined faces which cut forms an inverted "L" shape that extends vertically to a predetermined height from the distal bottom end; and (4) the grinding of the distal bottom end to form a triangular tip face which extends inclinedly from a front section to a rear section of the trapezoid tooth.

Abstract: A reduced resistance saw blade. The saw blade of the present invention has at least two or more groups of sawteeth, the groups of the sawteeth include a first group having a plurality of the sawteeth wherein the tips of the sawteeth are substantially situated on a first imaginary curve which changes in a periodic or irregular cycle, and a second group having a plurality of the sawteeth wherein the tips of the sawteeth are substantially situated on a second imaginary curve parallel to the first imaginary curve. Also provided is a saw blade which includes sets of the sawteeth having reversed set patterns, thus providing a saw blade which is capable of restraining deviation of the cut, maintaining the balance of the lateral sets of the overall saw blade. The saw blade of the present invention includes a plurality of sets of teeth, each set comprising unset, right set and left set teeth, wherein reversed set patterns with the same number of teeth are provided alternately.

Abstract: Circular brush cutting blade for powered brush cutter has cutting teeth arranged in pairs on periphery of blade, the teeth in pairs being of alternate right and left configuration and closely spaced together, the pairs of teeth being relatively widely spaced apart on the blade. Means are provided to engage the kerf sides and deflect the blade toward its central plane as it engages the material being cut.

Abstract: The present invention includes a bi-directional hacksaw blade that bites into and saws an object and clears particulate from a cut being formed in the object in each of the forward and rearward sawing directions. Each of the blade embodiments disclosed include a blade with two sets of teeth. The teeth of the first set is a mirror image of the teeth of the second set so that one set saws the object and the other set clears particulate in one sawing direction. In the opposite sawing direction, the roles of the teeth are reversed.

Abstract: Circular brush cutting blade for powered brush cutter has cutting teeth arranged in pairs on periphery of blade, the teeth in pairs being of alternate right and left configuration and closely spaced together, the pairs of teeth being relatively widely spaced apart on the blade. Means are provided to engage the kerf sides and deflect the blade toward its central plane as it engages the material being cut.