JIG saw blade with thick cutting edge and methods and systems of forming a finger joint using the JIG saw blade

Abstract

An improved jig saw blade is provided that includes an adapter and an elongate flat body. The adapter is configured to be secured into a clamp receptacle or chuck of a jig saw. The elongate flat blade body extends from the adapter along a longitudinal axis and defines a cutting edge with a plurality of cutting elements. The adapter has a first thickness, and the blade body has a second thickness greater than the first thickness of the adapter.

Description

JIG SAW BLADE WITH THICK CUTTING EDGE AND METHODS AND SYSTEMSOF FORMING A FINGER JOINT USING THE JIG SAW BLADECROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present disclosure claims priority from US Provisional Patent Appl. No. 63 / 655,969, filed on June 4, 2024, herein incorporated by reference in its entirety.BACKGROUND1. Field

[0002] The present disclosure relates to reciprocating saw blades, and more particularly, to reciprocating jig saw blades having a straight (non-curved) cutting edge.2, State of the Art

[0003] A finger joint is commonly used to connect two planks or pieces of material, such as wood, plastic or the like. An example finger joint 3 connecting two planks 1, 2 is shown in FIG. 1. The finger joint 3 is defined by fingers 30A formed in plank 1 and fingers 30B formed in plank 2. The fingers 30A, 30B interdigitate and help interlock planks 1 and 2. If planks 1 and 2 are connected at a right angle as shown in Fig. 2, the assembly is often referred to as a box joint. Regardless of the configuration, the interdigitating fingers 30A, 30B can provide both increased strength to the assembly, a leakproof container if glued and / or sealed appropriately as well as improved physical appearance.

[0004] FIG. 3 shows example fingers 30 that are used to form a finger joint (e.g., as shown in FIGS. 1 and 2). The fingers 30 are separated and defined by slots 31. A typical plank would have a plurality of fingers 30 and slots 31.

[0005] The typical method of machining these fingers 30 and slots 31 is shown in FIG. 4. The plank 40 is secured vertically on a table saw, or a platform 41 with a milling bit or a saw blade 42 defining the width of the slot (not shown) protruding upwards, and then sliding the plank 40 over the milling bit or saw blade to cut the slot. The plank 40 isthen indexed a fixed amount to the right or left and the slot repeated until the entire side of the plank 40 is slotted. This process is laborious for many reasons, First, if the plank 40 is several feet long, it becomes difficult to secure in place as well as slide over the blade or bit to make the next slot. In addition, each slot has to be positioned exactly as any discrepancy in indexing will add to the tolerance stack-up and render it extremely difficult to match the fingers with the contralateral plank. There is a definite need for a better method of making fingers and finger joints.

[0006] The fingers 30 can also be milled on a CNC router. A CNC router provides a simple mechanism of making finger joints as long planks can be used and secured horizontally on the bed of the router without the need to index the plank. In addition, other patterns can be cut on the same plank once fixtured on the router table. The CNC router bit can be programmed to index and cut the slots accurately and much quicker than the standard method of making finger joints depicted in FIG. 4. In addition, programming the router to mill the contralateral plank is relatively easy on a CNC router.

[0007] However, the interdigitation of the fingers 30 that form the finger joint made by the CNC router is problematic due to an artifact related to the milling bit used to cut the fingers 30. Referring back to FIG. 3, the milling bit path is shown as a dotted line 32 where the milling bit moves from a to b and onward. The milling bit is portrayed in FIG.3 as a cross-section disk 33. The fingers formed by the milling bit path are labeled 30, and the slots formed by the milling bit path are labeled 31. For each finger 30 to interdigitate completely with another finger (not shown), the base 34 of that finger 30 needs to be flat and squared with the side of the finger 30. That is, the corner 35 of the slot 31 needs to be square with the side 36. The square corner cannot be accomplished with a round milling bit. If, for example, a 1 / 4 inch milling bit is used to make the fingers 30, the comers 35 will be rounded or fileted at the 1 / 8” radius of the milling bit. The same is true for the fingers of the second plank that interdigitate with the fingers 30 as shown in FIGS. 1 and 2.

[0008] FIG. 5 shows planks 1 and 2 lined up for finger interdigitation to form a finger joint where the sharp corners of the fingers 30 interface to rounded filet corners of the slots 31. FIG. 6 shows that the gaps 60 formed where the sharp comers of the fingers 30of plank 1 interface to the rounded fileted corners in plank 2 as well as the gaps 61 formed where the sharp corners of the fingers 30 of plank 2 interface to the rounded fileted corners in plank 1. Similarly, FIG. 7 illustrates a box joint formed by planks 1 and 2, which has gaps 70 where the sharp corners of the respective fingers interface to the rounded fileted corners of the slots of the adjacent plank. Such gaps are problematic because they are not cosmetically appealing, and, if the box joint is used as a box comer, fluids can leak from the box.

[0009] Thus, there remains a need to provide a simple and effective tool to make finger joints that are formed by CNC milling yet avoid the gaps at the interface of the respective fingers and slots of the opposing planks.SUMMARY

[0010] An improved jig saw blade with thick cutting edge and methods and systems of forming a finger joint using the improved jig saw blade are disclosed.

[0011] In embodiments, an improved jig saw blade has an adapter configured to be secured into a clamp receptacle or chuck of a jig saw, and an elongate flat blade body that extends from the adapter along a longitudinal axis. The blade body defines a cutting edge with a plurality of cutting elements. The adapter has a first thickness, and the blade body has a second thickness greater than the first thickness of the adapter.

[0012] In embodiments, the second thickness can be defined in a direction orthogonal to the longitudinal axis of the blade body, and the first thickness can be defined in another direction orthogonal to the longitudinal axis of the blade body and parallel to the second thickness.

[0013] In embodiments, the second thickness of the blade body can define the cutting width of the blade body.

[0014] In embodiments, the second thickness can be at least two times the first thickness.

[0015] In embodiments, the second thickness can be three times the first thickness (or five times the first thickness).

[0016] In embodiments, the blade body can include a plurality of parts attached to one another to form a solid blade.

[0017] In embodiments, the plurality of parts can be attached to one another by adhesive, welds, one or more bolts, or a combination thereof.

[0018] In embodiments, the cutting elements of the plurality of parts can be aligned with one another across the second thickness of the blade body and along the length of the cutting edge of the blade body. In other embodiments, the cutting elements of the plurality of parts can be offset from one another across the second thickness of the blade body and / or along the length of the cutting edge of the blade body.

[0019] In embodiments, the cutting elements of the blade body can have a down-cut orientation. In other embodiments, the cutting elements of the blade body can have an up-cut orientation. In other embodiments, the cutting elements of the blade body can have a combination of up-cut as well as a down-cut orientations.

[0020] In embodiments, the adapter and the blade body of the improved jig saw blade can be formed entirely from one solid piece of metal.

[0021] In embodiments, the adapter of the improved jig saw blade can include two protrusions disposed opposite one another.

[0022] In another aspect, a method of forming a finger joint is disclosed that involves providing a finger joint formed by CNC milling, wherein the finger joint has rounded fileted corners in slots of the finger joint. The improved jig saw blade can be used to square off the rounded fileted corners of at least one slot of the finger joint.

[0023] In embodiments, the second thickness of the blade body is greater than the radius of the rounded fileted corners.

[0024] In yet another aspect, a method of forming a finger joint is disclosed that involves providing a jig saw mounted to a linear slide, wherein the jig saw is configured to receive an improved jig saw blade whereby the jig saw and jig saw blade are configured to slide together relative to a fixed backstop. A wood plank with finger joints formed by CNC milling is also provided. The finger joints includes rounded fileted corners in slots of the finger joint. The wood plank can be butted against the fixedbackstop. The jig saw and jig saw blade can be operated to cut the wood plank while sliding the jig saw and jig saw blade relative to the fixed backstop to square off at least rounded fileted corner of the finger joint.

[0001] This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The subject disclosure is further described in the detailed description which follows, in reference to the noted plurality of drawings by way of non-limiting examples of the subject disclosure, in which like reference numerals represent similar parts throughout the several views of the drawings, and wherein:

[0026] FIG. 1 is a schematic illustration of a finger joint that connects two planks.

[0027] FIG. 2 is a schematic illustration of a box joint that connects two planks.

[0028] FIG. 3 is a schematic illustration of part of a finger joint (or part of box joint) formed by CNC milling.

[0029] FIG. 4 is a schematic illustration of a standard method of forming a finger joint.

[0030] FIG. 5 is a schematic illustration of two planks aligned with one another for finger interdigitation to form a finger joint where the sharp comers of the fingers interface to rounded filet comers of the slots in the planks.

[0031] FIG. 6 is a schematic illustration of a finger joint formed by CNC milling, which shows gaps formed where the sharp comers of the fingers interface to rounded fileted corners in opposed planks.

[0032] FIG. 7 is a schematic illustration of a box joint formed by CNC milling, which shows gaps formed where the sharp corners of the fingers interface to rounded fileted corners in adjacent planks.

[0033] FIG. 8A is a schematic enface view of a conventional jig saw blade.

[0034] FIG. 8B is a schematic side view of the conventional jig saw blade of FIG.8A.

[0035] FIGS. 8C is a schematic enface view of another conventional jig saw blade.

[0036] FIG. 9A is a schematic enface view of an adapter-less blade portion that can be used to make an improved jig saw blade in accordance with one or more embodiments of the present disclosure.

[0037] FIG. 9B is a schematic side view of the adapter-less blade portion of FIG. 9A.

[0038] FIG. 10A is a schematic side view of an improved jig saw blade in accordance with a first embodiment of the present disclosure.

[0039] FIG. 10B is a schematic enface view of the improved jig saw blade of FIG. 10A.

[0040] FIG. 11 is a schematic side view of an improved jig saw blade in accordance with a second embodiment of the present disclosure.

[0041] FIG. 12 is a schematic side view of an improved jig saw blade in accordance with a third embodiment of the present disclosure.

[0042] FIG. 13 is a schematic diagram that shows the improved jig saw blade of FIGS. 10A and 10B squaring-off the rounded fileted comers of the slots of a finger joint initially formed in a piece of wood by CNC milling.

[0043] FIG. 14 is a schematic diagram that illustrates a method that removes rounded fileted corners of finger joints formed CNC milling by predrilling the comers of the slot prior to milling the slots of the finger joint.

[0044] FIGS. 15A and 15B are schematic drawings that illustrate a system that includes a jig saw fixtured on a movable platform in accordance with the present disclosure. The fixture enables the user to set the depth of the jig saw blade in a finger joint cut by the jig saw blade and to secure the workpiece to be cut in place.DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0045] The particulars shown herein are by way of example and for purposes of illustrative discussion of the embodiments of the subject disclosure only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the subject disclosure. In this regard, no attempt is made to show structural details in more detail than is necessary for the fundamental understanding of the subject disclosure, the description taken with the drawings making apparent to those skilled in the art how the several forms of the subject disclosure may be embodied in practice. Furthermore, like reference numbers and designations in the various drawings indicate like elements.

[0046] A jig saw is a well-known mechanical tool that imparts linear reciprocating movement to a conventional jig saw blade to cut a workpiece along a pathway. The pathway can be guided by manual movement of the jig saw by hand or by guided movement of the jig saw in a jig. The conventional jig saw blade includes an adapter or tang at one of the blade, and an elongate blade portion that extends from the adapter or tang to an opposed end of the blade. The adapter or tang and the elongate blade portion generally form a flat plate. The elongate blade portion has a straight (non-curved) cutting edge that defines a plurality of cutting teeth spaced relative to each other along one side / edge of the blade portion. The cutting teeth are oriented in the plane of the blade portion. Often, a non-working edge (without cutting teeth) is disposed on the opposite side / edge of the blade portion relative to the cutting edge. The jig saw includes a handle and a reciprocating clamp or chuck driven by an electrical motor (e.g., corded or battery- powered motor) and eccentric cam. The clamp or chuck is configured to releasably engage the adapter of the conventional jig saw blade. Linear reciprocating motion of the clamp or chuck drives linear reciprocating motion of the conventional jig saw blade engaged by the clamp or chuck. When the jig saw is operated to drive the linear reciprocating motion of the conventional jig saw blade and its cutting edge, the reciprocating cutting element can be brought into contact with the workpiece to cut the workpiece.

[0047] Most jig saws also include a shoe attached to the front end thereof, having a central opening through which the conventional saw blade extends. The shoe is adapted to engage the workpiece during cutting to stabilize and guide the reciprocating movement of the conventional jig saw blade into and out of the workpiece.

[0048] Manufacturers of jig saws include Rigid, Ryobi, DeWalt, Skil, Bauer, HyperTough, Milwaukee, Makita, and the like. All of these jig saws use a conventional jig saw blade having a straight (non-curved) cutting edge as shown in FIGS. 8A, 8B and 8C. FIGS. 8A and 8C are enface views of the conventional jig saw blade 89 in a reference X-Y-Z coordinate system where the X-axis extends in a direction toward the right side of the page, the Z-axis extends in a direction toward the top of the page, and the Y-axis extends in a direction out of the page. FIG. 8B is a side view of the conventional jig saw blade 89 of FIG. 8A in the reference X-Y-Z coordinate system where the Y-axis extends in a direction toward the right side of the page, the Z-axis extends in a direction toward the top of the page, and the X-axis extends in a direction out of the page. The conventional jig saw blade 89 includes an adapter 80 (which is also commonly referred to as a tang or T-shank) at one end of the blade 89, and an elongate blade portion 82 that extends from the adapter 80 to the opposed end 86 of the blade 89. The adapter 80 and the elongate blade portion 82 generally form a flat blade that extends in the Z direction as shown in FIGS. 8A and 8B. The adapter 80 has opposed protrusions 81 and 81’ as shown. The adapter 80 with the protrusions 81 and 81’ are configured to lock into a receptacle clamp or chuck on the jig saw (not shown) such that the electric motor and eccentric cam of the jig saw can impart linear reciprocating motion to the jig saw blade 89. The elongate blade portion 82 extends from the adapter 80 to the end 86 along a longitudinal axis 85 in the Z direction as shown. The elongate blade portion 82 has a straight (non-curved) cutting edge 83 that extends parallel to the longitudinal axis 85 and defines a plurality of cutting teeth spaced relative to each other along one side / edge of the blade portion 82 as shown. The cutting teeth provide cutting action in the plane of the blade portion 82 with a cutting direction extending in the X direction as shown. The elongate blade portion 82 also has a non-working edge 84 (without cutting teeth) that extends generally parallel to the longitudinal axis 85 on the opposite side / edge of the blade portion 82 relative to the cutting edge 83.

[0049] Typical dimensions for a conventional jig saw blade as referenced in FIGS. 8A and 8B include a length A between the opposed ends of the blade 92 of approximately 3.9 inches, a width B of the blade portion 82 of approximately 0.3 inches, a length C between the protrusion 81, 81’ of the adapter 80 and the near end of the blade 89 of approximately 0.5 inches, a width D of the adapter head 80 above the protrusions 81,81’ of approximately 0.25 inches, and a blade thickness E along the entire length of the blade 89 between the opposed ends of the blade 89 (including the adapter 80 and the blade portion 82) of approximately 0.054 inches. The lengths A and C extend generally along the Z direction as shown in FIG. 8A. The widths B and D extend generally along the X direction as shown in FIG. 8A. The blade thickness E extends in the Y direction as shown in FIG. 8B. The blade thickness E defines the thickness of the flat blade (including the adapter 80 and the blade portion 82). The blade thickness E also defines the width of the cutting action of the blade.

[0050] Note that FIGS. 8 A and 8B shows cutting elements of the cutting edge 83 oriented in the plane of the blade portion 82 downward away from the adapter 80, which is commonly referred to as a down-cut blade. FIG. 8C is similar to FIG. 8A, but the cutting elements of the cutting edge 83 are oriented in the plane of the blade portion 82 upward toward the adapter 80, which is commonly referred to as an up-cut blade.

[0051] Most furniture items having finger joints or box joints use wood planks of 0.25 inches to 1 inch in thickness (typically 0.75 inches in thickness). The slots between the fingers of each plank are generally the thickness of the wood planks. Assuming a wood thickness of 0.75 inches, it is typical to cut these slots on a CNC router using a milling bit of 0.25 inches in diameter. In this example, the milling bit will form rounded fileted comers of 0.125 inches in diameter. The conventional jig saw blade is 0.054 inches thick as described above, which makes it difficult to square-off the rounded fileted corners. It is therefore impractical to use a conventional jig saw blade to square-off the rounded fileted corners of the finger joints initially formed by the CNC router.

[0052] The present disclosure includes an improved jig saw blade with an adapter (which is also commonly referred to as a tang or T-shank) at one end of the blade, and an elongate blade body that extends from the adapter to the opposed end of the blade. Theadapter can include opposed protrusions similar to the conventional jigsaw blade. The adapter with protrusions is configured to lock into a receptacle clamp or chuck on the jig saw such that an electric motor and eccentric cam of the jig saw can impart linear reciprocating motion to the improved jig saw blade. The elongate blade body extends from the adapter along a longitudinal axis similar to the conventional jigsaw blade. The elongate blade body has a straight (non-curved) cutting edge that extends parallel to the longitudinal axis and defines a plurality of cutting elements spaced relative to each other along one side / edge of the blade body. The cutting elements provide cutting action in the plane of the blade body similar to the conventional jigsaw blade. The elongate blade body can also have a non-working edge (without cutting elements) that extends parallel to the longitudinal axis on the opposite side / edge of the blade body relative to the cutting edge similar to the conventional jigsaw blade.

[0053] The elongate blade body of the improved jig saw blade has a thickness greater than the thickness of the adapter of the improved jig saw blade, which is different from the elongate blade portion of the conventional jig saw blade where the adapter and the blade portion have a uniform blade thickness along the entire length of the blade (FIG. 8B). In embodiments, the elongate blade body of the improved jig saw blade can have a thickness greater than two times thickness of the adapter of the improved jig saw blade. This increased blade thickness increase the width of the cutting action of the improved jig saw blade as compared to the conventional jig saw blade. In embodiments, the thickness of the improved jig saw blade is defined in a direction orthogonal to the longitudinal axis of the elongate blade body of the improved jig saw blade, and the thickness of the adapter of the improved jig saw blade is defined in another direction orthogonal to the longitudinal axis of the elongate blade body and parallel to the thickness of the elongate blade body.

[0054] There are many ways of making the improved jig saw blade.

[0055] A simple method is shown in FIGS. 9A to 12.

[0056] FIGS. 9A and 9B show an adapter-less blade portion 82' formed by removing (sawing off) the adapter 80 of the conventional jig saw blade of FIGS. 8A and 8B. FIG. 9A is a plan view of the adapter-less blade portion 82' in a reference X-Y-Z coordinatesystem where the X-axis extends in a direction toward the right side of the page, the Z- axis extends in a direction toward the top of the page, and the Y-axis extends in a direction out of the page. FIG. 9B shows the side view of the adapter-less blade portion 82' of FIG. 9A in the reference X-Y-Z coordinate system where the Y-axis extends in a direction toward the right side of the page, the Z-axis extends in a direction toward the top of the page, and the X-axis extends in a direction out of the page.

[0057] FIGS. 10A and 10B show an improved jigsaw blade 99 formed by attaching three separate parts to one another. More specifically, the two adapter-less blade portions 82' of FIGS. 9A and 9B are attached to opposite sides of the blade portion 82 of the conventional jig saw blade of FIGS. 8A and 8B.

[0058] The improved jig saw blade 99 has an adapter at one end of the blade where the adapter is formed by the adapter 80 with protrusions 81, 81’ of the conventional jig saw blade. The adapter 80 with protrusions 81, 81’ is configured to lock into a receptable clamp or chuck on the jig saw (not shown) such that the electric motor and eccentric cam of the jig saw can impart linear reciprocating motion to the improved jig saw blade. The improved jig saw blade 99 also has an elongate flat blade body 101 that extends from the adapter 80 along a longitudinal axis 105 in the Z-direction to the opposed end 106 of the blade 99. As best shown in FIG. 10B, the blade body 101 has a straight (non-curved) cutting edge 103 that extends parallel to the longitudinal axis 105 and defines a plurality of cutting elements or teeth spaced relative to each other along one side / edge of the blade body 101. The cutting elements provide cutting action in the plane of the blade body 101 with a cutting direction extending in the X direction as shown. The elongate blade body 101 can also have a non- working edge 104 (without cutting elements) that extends parallel to the longitudinal axis 105 in the Z-direction on the opposite side / edge of the blade body 101 relative to the cutting edge 103.

[0059] The blade body 101 of the improved jig saw blade 99 includes three separate parts that are attached to another. More specifically, two adapter-less blade portions 82' (FIGS. 9A and 9B) are attached to opposite sides of the blade portion 82 of the conventional jig saw blade along the length of the blade body 101. The cutting edge 103 is defined by the cutting edges of the adapter-less blade portions 82' (FIGS. 9A and 9B)and the cutting edge of the blade portion 82 of the conventional jig saw blade disposed between the opposed adapter-less blade portions 82' along the length of the blade body 101. The non-working edge 104 is defined by the non- working edges of the opposed adapter-less blade portions 82' (FIGS. 9 A and 9B) and the non-working edge of the blade portion 82 of the conventional jig saw blade disposed between the opposed adapter-less blade portions 82' along the length of the blade body 101. In this embodiment, the thickness F of the blade body 101 is three-times the thickness E of the adapter 80 as shown in FIG. 10A.

[0060] In embodiments, the thickness F of the blade body 101 can be defined in a direction orthogonal to the longitudinal axis 105 of the blade body 101, and the thickness E of the adapter 80 can be defined in another direction orthogonal to the longitudinal axis 105 and parallel to the thickness F of the blade body 101 as shown in FIG. 10A.

[0061] The increased blade thickness of the improved jig saw blade 99 increases the width of the cutting action of the improved jig saw blade 99 as compared to the conventional jig saw blade (FIGS. 8A - 8C). For example, if the adapter 80 has a thickness of 0.054 inches, the blade body 101 will have a thickness of 0.162 inches. Such thickness of 0.162 inches is larger than the diameter of the rounded fileted corners of 0.125 inches formed by a CNC milling bit of 0.25 inches in diameter. Thus, the blade body 101 can be used to effectively square-off the rounded fileted corners in a finger joint formed by such CNC milling.

[0062] FIG. 11 shows an improved jigsaw blade 99' in a reference X-Y-Z coordinate system where the Y-axis extends in a direction toward the right side of the page, the Z- axis extends in a direction toward the top of the page, and the X-axis extends in a direction out of the page. The improved jigsaw blade 99' includes five separate parts that are attached to another. More specifically, two pairs of adapter-less blades 82' of FIGS. 9A and 9B are attached to one another and to opposite sides of the blade portion 82 of the jig saw blade of FIGS. 8 A and 8B in a similar manner as described above with respect to FIGS. 10A and 10B. In this embodiment, the thickness F’ of the blade body 101’ is five- times the thickness E of the adapter 80.

[0063] In embodiments, the thickness F’ of the blade body 101’ of improved jigsaw blade 99’ can be defined in a Y direction orthogonal to the longitudinal axis 105 (Z direction) of the blade body 101’, and the thickness E of the adapter 80 can be defined in another Y direction orthogonal to the longitudinal axis 105 (Z direction) and parallel to the thickness F’ of the blade body 101’ as shown in FIG. 11.

[0064] The increased blade thickness of the improved jig saw blade 99’ increases the width of the cutting action of the improved jig saw blade 99’ as compared to the conventional jig saw blade (FIGS. 8A - 8C). For example, if the adapter 80 has a thickness of 0.054 inches, the blade body 101’ will have a thickness of 0.27 inches. Such thickness of 0.27 inches is much larger than the diameter of the rounded fileted comers of 0.125 inches formed by a CNC milling bit of 0.25 inches in diameter. Thus, the blade body 101’ can be used to effectively square-off the rounded fileted comers in a finger joint formed by such CNC milling. Furthermore, if a 1 / 2 inch milling bit is used to make the finger joint, the radius of curvature at the back corners of the finger joint will be 1 / 4 inches (0.25 inches), therefore requiring a blade body thicker than 0.25 inches, such as the 0.27 inch thick blade body 101’ described above.

[0065] The parts that form the improved jigsaw blade 99 of FIGS. 10A and 10B (or the improved jigsaw blade 99' of FIG. 11) can be attached or secured together by many means. For example, an adhesive (such as cyanoacrylate) can be used to attach the adapter-less blade portions 82' to the blade portion 82 of the jigsaw blade of FIGS. 8 A and 8B. In another example, the adapter-less blade portions 82' can be welded to the blade portion 82 of the conventional jigsaw blade of FIGS. 8A and 8B. A preferred method of welding these blades together is TIG welding (Tungsten Inert Gas welding) also known as Gas Tungsten Arc Welding (GTAW), which is a type of arc welding process that uses a non-consumable tungsten electrode to create a weld. The weld would be formed on the backside of the blade. In yet another example, the adapter-less blades portions 82' can be bolted to the blade portion 82 of the jigsaw blade of FIGS. 8A and 8B as shown in FIG. 12. Combinations of the above attachment means can also be used.

[0066] In embodiments, the cutting elements of the different parts of the elongate flat blade body of the improved jig saw blades described herein can be aligned with oneanother across the thickness of the blade body and along the length of the cutting edge of the blade body. In other embodiments, one or more cutting elements of the different parts of the elongate flat blade body of the improved jig saw blades described herein can be offset from one another across the thickness of the blade body and / or along the length of the cutting edge of the blade body.

[0067] In embodiments, the cutting elements of the cutting edge of the elongate flat blade body of the improved jig saw blade described herein can have a down-cut orientation extending away from the adapter of the improved jig saw blade, which is easier to fixture and handle. In alternative embodiments, the cutting elements of the cutting edge of the elongate flat blade body of the improved jig saw blade described herein can have an up-cut orientation extending toward the adapter of the improved jig saw blade. In still alternative embodiments, the improved jig saw blade described herein can have a mixture of up-cut and down-cut blades.

[0068] In alternate embodiments, the adapter and elongate flat blade body of the improved jigsaw blades described herein can be formed entirely from one solid piece of metal and stamped, laser cut, wire EDMed, and the like to form the contours and cutting elements required.

[0069] Note that the configurations of the blade body of the improved jigsaw blades described herein can be used to form a slot of a finger joint or box joint with a square corner.

[0070] FIG. 13 shows the improved jig saw blade 99 of FIGS. 10A and 10B squaring-off the rounded fileted comers of the slots of a finger joint initially formed in a piece of wood 1300 by CNC milling. The cutting edge 103 of the blade 99 can be as thick as the width of the slot to square-off two rounded filet corners of the slot at the same time. Alternatively, the cutting edge 103 of the blade 99 can be slightly thicker than the radius of the rounded filet corner and the rounded filet corners can be squared off one at a time by cutting action of the cutting edge 103 of the blade 99 and sliding the blade 99 from one side of the slot to the other.

[0071] Those well versed in machining can also appreciate that a simple rig can be constructed to hold the jig saw stationary, and the blade 99 perpendicular to the woodpiece / plank 130-to be cut. In this configuration, the slots of the fingers previously cut on the CNC machine can be slid into this fixture to a predetermined distance where the rounded filet comers can be squared off without deepening or damaging the slot.

[0072] Those well versed in machining can appreciate that rounded fileted corners formed by CNC milling can be removed by predrilling the comers of the slot prior to milling the slot as shown in FIG. 14. This forms holes 140 at the corner of the slots as shown.. Alternatively other patterns can be machined first to remove the rounded fileted corners. However, the problem with these methods of removing filets is that they are not cosmetically appealing and if used as a box comer, fluids can leak from the box.

[0073] In another aspect of the present disclosure, a jig saw can be fixtured on a movable platform to set the depth of the blade in the finger joint and to secure the workpiece to be cut in place. FIG. 15A shows a jig saw 150, integrally attached to base platform 151, with blade clamp 152 and jig saw blade 153. Blade clamp 152 contains a spring-loaded lever or knob that is pulled or twisted to open the clamp. The adapter 80 of the jig saw blade 153 (which can be any one of the jig saw blade embodiments described herein) is inserted into blade clamp 152 and the lever released to lock the jig saw blade 153 in place. Alternatively, some older model jig saws use set screws to hold the jig saw blade 153 in place (not shown).

[0074] It is desirable to adjust the jig saw blade 153 to precisely fit the depth of the finger joint to effectuate squaring off the rounded fileted corners of the finger joint. A means of providing such is to secure jig saw 150 to a linear slide 154. Linear slide 154 is comprised of linear bearing 155 which is rotatably fixed to block 157. When linear bearing 155 is rotated clockwise or counterclockwise, slidable stage 156 is moved left or right. Slidable stage 156 is attached to a platform 151 of jig saw 150 by means of bolts, or the like. This mechanism allows jig saw blade 153 to move left and right relative to base 157 which is stationary.

[0075] Scissors table 160 is used to raise and lower the workpiece to be cut, which in this case is a wood plank 158 with previously CNC-cut finger joints with rounded fileted corners. It is desirable to place the wood plank 158 slidingly between the bottom of jig saw platform 151 and the top 161 of scissors table 160. Note that when a down-cut bladeis used, the wood plank 158 need not be butted up against the underside of platform 151 as the force of the down-cut presses the wood plank 158 against the top 161 of scissors table 160. In this manner, the wood plank 158 can be moved right, to butt-up against base 157 at position 159, and once butted against base 157, it can be slid in and out of the plane of the drawing to effectuate squaring off one or more rounded fileted comers the finger joint.

[0076] Once the rounded fileted comer(s) the finger joint in the wood plank 158 has been squared off, the wood plank 158 can be withdrawn as illustrated in Fig. 15B and manually moved to the next finger joint, if desired.

[0077] Although the above describes the use of a jig saw blade with a standard adapter to fit into a standard blade clamp, a jig saw can be configured with a blade clamp that can be used to fit a blade of any thickness. In this case, a wide blade of uniform thickness without a thin adapter section can be made to fit this reconfigured jig saw.

[0078] There have been described and illustrated herein several embodiments of an improved jig saw blade with a thick cutting edge and methods and systems of forming a finger joint using the improved jig saw blade. While particular embodiments of the invention have been described, it is not intended that the invention be limited thereto, as it is intended that the invention be as broad in scope as the art will allow and that the specification be read likewise. It will therefore be appreciated by those skilled in the art that yet other modifications could be made to the invention without deviating from its spirit and scope as claimed.

Claims

WHAT IS CLAIMED IS:

1. A jig saw blade comprising: an adapter configured to be secured into a clamp receptacle or chuck of a jig saw; and an elongate flat blade body that extends from the adapter along a longitudinal axis, wherein the blade body defines a cutting edge with a plurality of cutting elements; wherein the adapter has a first thickness, and the blade body has a second thickness greater than the first thickness of the adapter.

2. A jig saw blade according to claim 1, wherein: the second thickness is defined in a direction orthogonal to the longitudinal axis of the blade body, and the first thickness is defined in another direction orthogonal to the longitudinal axis of the blade body and parallel to the second thickness.

3. A jig saw blade according to claim 1, wherein: the second thickness of the blade body defines the cutting width of the blade body.

4. A jig saw blade according to claim 1, wherein: the second thickness is at least two times the first thickness.

5. A jig saw blade according to claim 4, wherein: the second thickness is three times the first thickness; or the second thickness is five times the first thickness.

6. A jig saw blade according to claim 1, wherein: the blade body comprises a plurality of parts attached to one another to form a solid blade.

7. A jig saw blade according to claim 4, wherein: the plurality of parts are attached to one another by adhesive, welds, one or more bolts, or a combination thereof.

8. A jig saw blade according to claim 4, wherein: the cutting elements of the plurality of parts are aligned with one another across the second thickness of the blade body and along the length of the cutting edge of the blade body.

9. A jig saw blade according to claim 4, wherein: the cutting elements of the plurality of parts are offset from one another across the second thickness of the blade body and / or along the length of the cutting edge of the blade body.

10. A jig saw blade according to claim 1, wherein: the cutting elements of the blade body have a down-cut orientation; or the cutting elements of the blade body have an up-cut orientation, or the cutting elements of the blade body have a combination of down-cut orientation and up-cut orientation.

11. A jig saw blade according to claim 1, wherein: the adapter and the blade body are formed entirely from one solid piece of metal.

12. A jig saw blade according to claim 1, wherein: the adapter includes two protrusions disposed opposite one another.

13. A method of forming a finger joint, the method comprising: providing a finger joint formed by CNC milling, wherein the finger joint has rounded fileted corners in slots of the finger joint; and using the jig saw blade of claim 1 to square off the rounded fileted comers of at least one slot of the finger joint.

14. A method according to claim 13, wherein: the second thickness of the blade body is greater than the radius of the rounded fileted comers.

15. A method of forming a finger joint, comprising: providing a jig saw mounted to a linear slide, wherein the jig saw is configured to receive a jig saw blade according to claim 1, whereby the jig saw and jig saw blade are configured to slide together relative to a fixed backstop; providing a wood plank with a finger joint formed by CNC milling, wherein the finger joint includes rounded fileted comers in slots of the finger joint; butting the wood plank against the fixed backstop; and operating the jig saw and jig saw blade to cut the wood plank while sliding the jig saw and jig saw blade relative to the fixed backstop to square off at least rounded fileted corner of the finger joint.

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