Patent Publication Number: US-2023150047-A1

Title: Guide dresser, cutter heads and methods of use thereof

Description:
TECHNICAL FIELD 
     The present disclosure generally relates to a guide dresser, cutter heads and methods of use thereof, and more particularly to guide dressers having movable cutter assemblies for milling a saw guide. 
     BACKGROUND 
     Production of lumber from raw logs typically involves a first step, called primary breakdown, which involves recovering an elongate square center from a log using head rig equipment. Head rigs generally comprise a large stationary circular saw or a band saw and a travelling carriage. The travelling carriage rotationally transports a log back and forth through the head rig to remove a series of rounded slabs from outer edges of the log thereby producing the squared center of the log, which is commonly called a “cant”. In some processes, cants are produced with two squared-off opposing sides. Primary breakdown typically produces 2-sided and 4-sided cants, rounded edge slabs, and sometimes, large boards. 
     The cants, slabs and boards produced during primary breakdown are further processed during secondary breakdown processes whereby large rectangular side flitches having two opposing parallel sides, are cut from the sides of cants with band saws or circular saws. Flitches are then typically broken down into functional lumber with equipment having multiple parallel circular saw blades mounted onto a fixed driven arbor, commonly known as circular gang saws. The processing step for producing flitches from cants is known as “reducing” while production of functional lumber from flitches comprises multiple steps referred to as “edging” and “re-sawing”. High volume throughput systems often combine the reducing and edging steps into one piece of equipment operating under high saw speeds to enable rapid cutting of wood against high pressures forced by rapid throughput of cants and flitches. 
     Pressing forces applied by high volume throughput of flitches and lumber pieces against circular gang saws often cause undesired lateral movements and vibrations of individual saw blades resulting in deterioration in blade stability and reduced dimensional accuracy in the final finished lumber pieces. It is common practice to provide saw guides interposed between individual blades to maintain their spacing and to minimize the extent of vibration that may occur. The saw guides are securely fixed into place between the individual circular blades by engagement with equipment frame rails or other support elements to provide stability to the saw blades prior to commencing operations. 
     Accurate saw guides improve the performance of the saws (e.g. gang saws) in the production of lumber. In this regard, guide dressers have been developed to mill and machine saw guides to improve and maintain their longevity and accuracy. However, existing guide dressers and cutter heads are not accurate enough to maintain saw guides within desired tolerances. Also, existing guide dressers and cutters are difficult to set properly. 
     A need therefore exists for an improved guide dresser and cutter heads that exhibit ease of use and a high degree of accuracy in milling and machining saw guides. 
     SUMMARY 
     The present disclosure provides guide dressers, cutter heads and methods for milling or machining a saw guide. The present disclosure recognizes that there are problems in the current existing guide dresser technologies in respect of the apparatus, cutter heads and methods, and provides an improved guide dresser and cutter heads. 
     An advantage of the present disclosure is the provision of guide dressers and components thereof (e.g. cutter assemblies, cutter heads, etc.) having improved characteristics over existing technologies, tools, processes and systems. 
     In an embodiment, the present disclosure relates to a guide dresser for milling a saw guide, the guide dresser comprising: a rail or slide system; a first cutter assembly slidably mounted on the rail or slide system, the first cutter assembly having a first rotatable cutter head; a second cutter assembly slidably mounted on the rail or slide system, the second cutter assembly having a second rotatable cutter head; and a guide mount for receiving and maintaining in a stationary position a saw guide, the stationary position being between the first rotatable cutter head and the second rotatable cutter head and the rail or slide system aligned for moving each of the first cutter assembly and second cutter assembly towards or away from the guide mount, the guide dresser being adjustable between an open position and a closed position by slidable movement of the first cutter assembly, the second cutter assembly, or both, wherein: when in the open position, one or both of the first cutter assembly and the second cutter assembly are positioned away from the guide mount on the rail system, and when in the closed position, both the first cutter assembly and the second cutter assembly are positioned proximal to the guide mount on the rail system, such that both the first cutter head and second cutter head are capable of contacting the saw guide when it is received within the guide mount. 
     In an embodiment, the present disclosure relates to a method for milling a saw guide, the method comprising: moving a first cutter assembly and a second cutter assembly on a rail or slide system to engage a first cutter head of the first cutter assembly and a second cutter head of the second cutter assembly against opposing sides of a stationary saw guide; and milling or machining the stationary saw guide. 
     In an embodiment, the present disclosure relates to a cutter head, the cutter head comprising a circular disc and one or more removable knife retention apparatuses, each of the one or more removable knife retention apparatuses for receiving a knife. 
     In an embodiment, the present disclosure relates to a cutter head, the cutter head comprising a circular disc having two or more grooves on a face thereof, each groove of the two or more grooves for receiving two or more cutting implements. 
     In an embodiment, the present disclosure relates to a kit comprising one or more components of the cutter heads described herein. For example, in an embodiment, the present disclosure relates to a kit comprising a circular disc for use as a cutter head, and one or more removable knife retention apparatuses. The kit may further comprise one or more knives for mounting in each of the removable knife retention apparatuses. In another embodiment, the kit may comprise a circular disc having two or more grooves on a face thereof for use as a cutter head, and two or more cutting implements. 
     Other aspects and embodiments of the disclosure are evident in view of the detailed description provided herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further advantages, permutations and combinations of the invention will now appear from the above and from the following detailed description of the various particular embodiments of the invention taken together with the accompanying drawings, each of which are intended to be non limiting, in which: 
         FIGS.  1 A-B  are side views of a guide dresser according to some embodiments of the present disclosure, wherein  FIG.  1 A  shows the guide dresser in an open position and  FIG.  1 B  shows the guide dresser in a closed position. 
         FIGS.  2 A-B  are top views of the guide dresser shown in  FIGS.  1 A-B , wherein  FIG.  2 A  is the guide dresser in the open position and  FIG.  2 B  is the guide dresser in the closed position. 
         FIGS.  3 A-E  show an exemplary cutter head of the present disclosure shaped as a circular disc and having knives contained within knife retention apparatuses.  FIG.  3 A  is a perspective view of a front side,  FIG.  3 B  is a top view of the front side,  FIG.  3 C  is a perspective view of a back side,  FIG.  3 D  is a side view, and  FIG.  3 E  is an extracted view of an exemplary knife retention apparatus. 
         FIGS.  4 A-C  show another exemplary cutter head of the present disclosure shaped as a circular disc and having carbide inserts as the milling implement.  FIG.  4 A  is a perspective view of a front side,  FIG.  4 B  is a top view of the front side, and  FIG.  4 C  is a side view. 
         FIGS.  5 A-B  show a cutter assembly according to some embodiments of the present disclosure, wherein  FIG.  5 A  is a front view and  FIG.  5 B  is a cross-sectional view along the A-A line sown in  FIG.  5 A . 
         FIG.  6    is an exploded perspective view of an exemplary pivot component for use in association with embodiments of the cutter assembly of the present disclosure. 
         FIG.  7    is an exploded perspective view of a two-part pivotable block component for use in association with embodiments of the cutter assembly of the present disclosure 
     
    
    
     DETAILED DESCRIPTION 
     Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the disclosure belongs. Although any methods and materials similar to or equivalent to those described herein can be used in the practice or testing of the present disclosure, the suitable methods and materials are described below. 
     The embodiments of the present disclosure pertain to guide dressers, cutter heads and methods having improved functionality for milling and machining saw guides. Guide dressers of the present disclosure have moveable cutter assemblies for engaging and disengaging a saw guide. In select embodiments, cutter assemblies are slidably mounted on a rail or slide system so as to be adjustable between an open position and a closed position. Cutter heads of the present disclosure have unique features and configurations for improved milling of a saw guide. 
     The present disclosure provides a number of advantages over existing technologies. For example, existing guide dressers are not accurate enough and are difficult to set properly. This is due to a number of factors, including for example the saw guide being fed into the cutters. Moreover, existing cutter heads are often set in position by hand and are rarely capable of milling a saw guide to desired or even acceptable tolerances. 
     An advantage of the present disclosure is the provision of guide dressers having improved characteristics over existing technologies, in particular having fewer moving parts and using a configuration by which improved cutter heads are moved directly into a saw guide for milling and machining operations. In the guide dressers of the present disclosure, the saw guide remains stationary and the cutter heads are fed into the saw guide on slidably mounted cutter assemblies. In certain embodiments, the process is automated and the cutter heads on respective cutter assemblies are fed into the saw guide using programmable computer numerical control (CNC) programming. 
     In some embodiments, the present disclosure relates to a guide dresser for milling a saw guide, the guide dresser comprising: a rail or slide system; a first cutter assembly slidably mounted on the rail or slide system, the first cutter assembly having a first rotatable cutter head; a second cutter assembly slidably mounted on the rail or slide system, the second cutter assembly having a second rotatable cutter head; and a guide mount for receiving and maintaining in a stationary position a saw guide, the stationary position being between the first rotatable cutter head and the second rotatable cutter head and the rail or slide system aligned for moving each of the first cutter assembly and second cutter assembly towards or away from the guide mount, the guide dresser being adjustable between an open position and a closed position by slidable movement of the first cutter assembly, the second cutter assembly, or both, wherein: when in the open position, one or both of the first cutter assembly and the second cutter assembly are positioned away from the guide mount on the rail system, and when in the closed position, both the first cutter assembly and the second cutter assembly are positioned proximal to the guide mount on the rail system, such that both the first cutter head and second cutter head are capable of contacting the saw guide when it is received within the guide mount. 
     It will be appreciated that while the exemplary embodiments of the guide dresser as shown in the figures herein have the rail or slide system in a horizontal orientation generally parallel to the ground or floor, other configurations are contemplated, such as for example where the slide or rail system is tilted or in an up/down configuration. The rail or slide system also need not provide slidable movement in a linear direction, but may also provide a curved path of movement or any other configuration. 
     Reference will now be made in detail to exemplary embodiments of the disclosure, wherein numerals refer to like components, examples of which are illustrated in the accompanying drawings that further show exemplary embodiments, without limitation. 
       FIGS.  1 A-B  and  FIGS.  2 A-B  illustrate side and top views, respectively, of an exemplary embodiment of a guide dresser  10  according the present disclosure. The guide dresser  10  as shown in  FIGS.  1 A-B  and  FIGS.  2 A-B  comprises a rail or slide system  12 , a first cutter assembly  20  having a first rotatable cutter head  22  and a motor  24 , a second cutter assembly  30  having a second rotatable cutter head  32  and a motor  34 , and a guide mount  40 . The guide mount  40  is capable of receiving a saw guide  50 . 
     In the guide dressers of the present disclosure, the first cutter assembly  20  and the second cutter assembly  30  are slidably mounted on the rail or slide system  12 . By “rail or slide system”, it is meant to refer to any arrangement of components that allow for movement of the first and second cutter assemblies ( 20 ,  30 ). The rail or slide system  12  may, for example and without limitation, include wheels, tracks, trolleys, grooves, slides, bearings, or any combination thereof. In an embodiment, the rail or slide system  12  is a track-and-trolley system. In an embodiment, the rail or slide system  12  comprises a ballscrew and linear bearings. By “slidably mounted”, it is meant to refer to any type of movement whereby the cutter assembly ( 20 ,  30 ) is moved from one position to another while attached to the rail or slide system  12 , or components thereof. The first cutter assembly  20  and the second cutter assembly  30  may be mounted on, or attached to, the rail or slide system  12  by any suitable means. 
     In some embodiments of the present disclosure, the rail or slide system  12  comprises a single continuous rail or slide component having both the first cutter assembly  20  and the second cutter assembly  30  slidably mounted thereon. For example, the rail or slide system  12  may extend a length that traverses past (e.g. in front of) the guide mount  40 , with the first cutter assembly  20  mounted on the rail or slide system  12  on one side of the guide mount  40 , and the second cutter assembly  30  mounted on the rail or slide system  12  on the other side of the guide mount  40 . 
     In other embodiments, the rail or slide system  12  comprises a separate apparatus or structure for each of the first cutter assembly  20  and the second cutter assembly  30 . For example, as shown in  FIGS.  1 A-B  each of the first cutter assembly  20  and the second cutter assembly  30  may be mounted on its own rail or slide apparatus ( 14   a,    14   b ). 
     The rail or slide system  12  may be configured for linear movement of each cutter assembly ( 20 ,  30 ), meaning that the cutter assemblies ( 20 ,  30 ) are moved along a straight path in the rail or slide system  12 . Alternatively, the rail or slide system  12  may have a configuration that provides for non-linear movement of the cutter assemblies ( 20 ,  30 ). For example, the cutter assemblies ( 20 ,  30 ) may travel along a curved or arched path to approach the position of the guide mount  40 . 
     Irrespective of the configuration of the rail or slide system  12 , movement of the cutter assemblies ( 20 ,  30 ) may be manual, automated, or any combination thereof. In an embodiment, the position of each cutter assembly ( 20 ,  30 ) on the rail or slide system  12  is controlled with programmable controller, such as a programmable logic controller (PLC) and/or computer numerical control (CNC) programming. In an embodiment, the rail or slide system  12  comprises its own independent motor to drive movement of each cutter assembly ( 20 ,  30 ) on the rail or slide system  12 . The motor may, for example, be a servo motor. In an embodiment, the rail or slide system  12  comprises servo motor-controlled ballscrew and linear bearings for programmable and repeatable positioning of each cutter assembly ( 20 ,  30 ). The rpm and spherical alignment of the cutter heads ( 22 ,  32 ) may also be similarly control by manual processes, automated processes, or a combination thereof. 
     Referring again to  FIGS.  1 A-B  and  FIGS.  2 A-B , the first cutter assembly  20  and the second cutter assembly  30  each have respective rotatable cutter heads ( 22 ,  32 ). As used herein, the term “rotatable cutter head” is intended to refer to the cutting apparatus for engaging and milling a saw guide  50 . The rotatable cutter head is, for example, mounted on a spindle to which rotational movement is applied. The rotational movement may be from any suitable source. In an embodiment, each cutter assembly ( 20 ,  30 ) has a motor ( 24 ,  34 ) to drive the rotational movement. The motor ( 24 ,  34 ) may, for example, be a belt drive motor which supplies rotational movement to a belt that is connected to both the motor and a spindle connect to the cutter heads ( 22 ,  32 ). In some embodiments, each cutter assembly ( 20 ,  30 ) has its own motor ( 24 ,  34 ) and drive system for providing rotational movement to the cutter heads ( 22 ,  32 ). In other embodiments, a single motor may be used to provide rotational movement to the cutter heads ( 22 ,  32 ) on both cutter assemblies ( 20 ,  30 ). Other arrangement and configurations to provide rotational movement to the cutter heads ( 22 ,  32 ) will be well-appreciated by the skilled person. 
     In operation, the guide dressers of the present disclosure maintain a saw guide  50  in a stationary position. In this regard, the guide dressers comprise a guide mount  40  for receiving and maintaining a saw guide  50  in this stationary position. By “stationary position”, it is meant that the saw guide  50  is held in a fixed or substantially fixed position while one or both of the cutter assemblies ( 20 ,  30 ) are moved along the rail or slide system  12  to engage the saw guide  50 . The guide mount  40  is configured for removable attachment of the saw guide  50  and is of sufficient strength to withstand the forces imparted by the cutter heads ( 22 ,  32 ) and keep the saw guide  50  stationary during milling operations. 
     The guide mount  40  is in a suitable position on the guide dresser  10  to place the saw guide  50  between the first rotatable cutter head  22  and the second rotatable cutter head  32 . By this, it is meant that when the first cutter assembly  20  and second cutter assembly  30  travel to an end of, or position on, the rail or slide system  12  that is proximal to the guide mount  40 , the cutter heads ( 22 ,  32 ) are positioned so as to be capable of engaging the saw guide  50  for milling and machining operations. In some embodiments, the guide mount  40  is positioned between the first cutter assembly  20  and second cutter assembly  30 , but slightly askew so that the guide mount  40  does not interfere with the ability of the cutter heads ( 22 ,  32 ) to contact the saw guide  50 . In some embodiments, the guide mount  40  is positioned to one side of the guide dresser  10  and the guide mount  40  has an extension component that places the saw guide  50  in the stationary position between the first rotatable cutter head  20  and the second rotatable cutter head  30 . 
     In operation, the rail or slide system  12  permits movement or travel of the first rotatable cutter head  20  and the second rotatable cutter head  30  towards and away from the guide mount  40  to alternate between an “open position” and a “closed position”. Thus, the guide dresser  10  of the present disclosure is capable of being adjusted between an open position and a closed position. 
     As used herein, the expression “open position” is intended to refer to a configuration of the guide dresser  10  whereby both the first cutter assembly  20  and second cutter assembly  30  are positioned away from the guide mount  40  on the rail or slide system  12 . By “positioned away”, it is meant that the cutter assembly ( 20 ,  30 ) is in a position on the rail or slide system  12  that the cutter head ( 22 ,  32 ) would not be capable of engaging or contacting the saw guide  50  when the saw guide  50  is received by the guide mount  40 . In an embodiment, in the open position both the first cutter assembly  20  and second cutter assembly  30  are positioned as far away from the guide mount  40  as is permitted by the rail or slide system  12 . In other embodiments, the first cutter assembly  20  and second cutter assembly  30  may independently be at any distance away from the guide mount  40  along the rail or slide system  12 , and each may be at the same or a different distance away from the guide mount  40 . 
     As used herein, the expression “closed position” is intended to refer to a configuration of the guide dresser  10  whereby both the first cutter assembly  20  and second cutter assembly  30  are positioned such that both the first cutter head  22  and second cutter head  32  are capable of contacting the saw guide  50  when it is received within the guide mount  40 . In the closed position, the guide dresser  10  can operate to mill both sides of the saw guide  50 . 
     In addition to the open position and closed position, it should be understood that the guide dresser  10  disclosed herein is capable of being operated in such a manner that only one of the cutter assemblies ( 20 ,  30 ) is positioned to allow the cutter head ( 22 ,  32 ) to engage or contact the saw guide  50 , and thereby mill a single side of the saw guide  50 . 
     In an embodiment, the guide dresser  10  of the present disclosure is fully enclosed within an encasement having a door. In an embodiment, the door is located to provide access to the guide mount  40 . For milling a saw guide  50 , a user or automated controller need only open the door and install a saw guide  50  on the guide mount  40 . Installation of the saw guide  50  on the guide mount  40  is an easy process and is accurately repeatable to provide for reliability in accuracy of milling. In an embodiment, the guide dresser  10  can only be operated when a magnetic door lock is engaged. 
     Referring now to  FIGS.  3 A to  3 E , each cutter assembly of the present disclosure includes a cutter head ( 22 ,  32 ). An embodiment of a cutter head ( 22 ,  32 ) of the present disclosure is shown in  FIGS.  3 A to  3 E . In this embodiment, the cutter head ( 22 ,  32 ) comprises a circular disc  60  and one or more removable knife retention apparatuses  70 , each of the one or more removable knife retention apparatuses for receiving a knife  80 . The circular disc  60  is shaped like a wheel, having a front surface, a back surface and an outer perimeter surface. The circular disc  60  may have apertures traversing from its front surface to back surface. By “front surface” it is meant the side that performs the milling of the saw guide  50 , and the back surface is the opposite side. Each of the knife retention apparatuses  70  can be permanently or removably mounted on the front surface of the circular disc  60 . 
     In an embodiment, the knife retention apparatus  70  is a configuration that can be removably mounted to the circular disc  60 . An exemplary embodiment is shown in  FIG.  3 E  where the knife retention apparatus  70  comprises a knife holder  72 , a knife gib  74 , a knife clamp  76 , and one or more knife gib screws  78 . In this configuration, the knife  80  is positioned between the knife holder  72  and the knife gib  74 , with the knife jib  74  pressing against the knife  80  by way a force applied from the one of more knife screws  78 . The knife clamp  76  is on the opposite side of the knife screws  78  from the knife gib  74  to act as a counterbalance to the force of the knife screws  78 , for example by way of opposing notches in the knife gib  74  and knife clamp  76  into which at least a portion of the knife screw  78  is received. In some embodiments, the knife holder  72  and the knife clamp  76  include one or more mounting apertures for receiving a pin  82  protruding from the circular disc  60 . In an embodiment, the pins  82  are dowel pins. The mounting apertures and pins  82  provide accuracy and rigidity the positioning of the knife retention apparatus  70 , and therefore the position of the knife  80 . 
     Many adjustments to the configuration of the knife retention apparatus  70  can be made. For example, the knife holder  72  can be manufactured to allow any desired knife angle by adjusting the angle of the wall of the knife holder  72  against which the knife  80  is held. In an embodiment, the angle can be any angle between about 15.0° and about 80.0° relative to the front surface of the circular disc  60 . In an embodiment, the angle is between about 45.0° and about 75.0° relative to the front surface of the circular disc  60 . As shown in  FIG.  3 A , the knife holder  72 , knife gib  74 , and knife clamp  76  may be of an elongate shape configured to substantially span a radius of the circular disc  60  when mounted on the circular disc  60 . By “elongate shape”, it is meant a structure that is longer in one direction (e.g. length) than in other directions (e.g. width, height). For example, and without limitation, an elongate shape may be similar to a rectangle in shape. By “substantially span a radius of the circular disc”, it is meant to extend from near the center of the circular disc  60  to near the outer edge of the circular disc  60 . This shape and configuration may be preferred for rigidity and accuracy, but other configurations can also be used. 
     In an embodiment, each knife retention apparatus  70  includes two or more knife screws  78 . In an embodiment, each knife retention apparatus  70  includes 2, 3, 4, 5 or more knife screws  78 . In an embodiment, each knife retention apparatus  70  includes three knife screws  78 . 
     The cutter head ( 22 ,  32 ) may include any number of the knife retention apparatuses  70  on the circular disc  60 . In an embodiment, cutter head ( 22 ,  32 ) includes 2, 3, 4, 5, 6, 7, 8, 9, 10 or more knife retention apparatuses  70  on the circular disc  60 . In a particular embodiment, cutter head ( 22 ,  32 ) includes 3, 4 or 5 knife retention apparatuses  70  on the circular disc  60 . The components of the knife retention apparatuses  70  may mounted on the circular disc  60  by any suitable means. In an embodiment, the knife retention apparatus  70  is mounted to the circular disc  60  by screws, bolts or other types of fasterners. In operation, each knife retention apparatus  70  would have a knife  80  received therein, with the blade protruding outwards. 
     Another exemplary embodiment of a cutter head ( 22 ,  32 ) of the present disclosure is shown in  FIGS.  4 A to  4 C . In this embodiment, the cutter head ( 22 ,  32 ) comprises a circular disc  90  having grooves  92  on a front face thereof. By “front surface” it is again meant the side that performs the milling of the saw guide  50 . Similar to circular disc  60 , circular disc  90  having grooves  92  may have apertures traversing from its front surface to back surface. By “grooves”, it is meant an indent or depression in the surface. 
     The grooves  92  may be of any suitable shape to receive two or more cutting implements  94 . In an embodiment, each groove  92  is an elongate shape configured to substantially span a radius of the circular disc. By “elongate shape”, it is meant an indent or depression that is longer in one direction (e.g. length) than in other directions (e.g. width, height). For example, and without limitation, an elongate shape of groove  92  may be a channel, in particular a linear channel. By “substantially span a radius of the circular disc”, it is meant to extend from near the center of the circular disc  60  to near or at the outer edge of the circular disc  60 . As shown in  FIG.  4 A , in an embodiment groove  92  extends from near the center of the circular disc  60  to the outer perimeter, with a portion of the outer perimeter surface also removed to form the groove  92 . In other embodiments, the groove  92  may not extend into the outer perimeter surface, but rather may end just before the outer edge of the circular disc  92 . 
     The cutter head ( 22 ,  32 ) may include any number of grooves. In an embodiment, the cutter head ( 22 ,  32 ) has at least two grooves  92 . In an embodiment, the cutter head ( 22 ,  32 ) has 2, 3, 4, 5, 6, 7, 8, 9, 10, or more grooves  92 . In an embodiment, the cutter head ( 22 ,  32 ) has 3, 4 or 5 grooves  92 . In an embodiment, the cutter head ( 22 ,  32 ) has 3, 4 or 5 grooves  92  and each of the grooves  92  is an elongate shape configured to substantially span a radius of the circular disc. In an embodiment, the cutter head ( 22 ,  32 ) has three grooves  92  and each of the grooves  92  is an elongate shape configured to substantially span a radius of the circular disc. 
     The cutting implements  94  may be positioned at any suitable position within the groove  92  to expose a cutting surface for milling a saw guide  50 , and there may be any suitable number of cutting implements  94  within each groove  92 . In an embodiment, each groove  92  has at least two cutting implements  94  that are separate from each other. In an embodiment, each groove  92  independently has 2, 3, 4, 5, 6, 7, 8, 9, 10, or more cutting implements  94  that are separate from each other. In an embodiment, each groove  92  independently has 3, 4 or 5 cutting implements  94  that are separate from each other. Each groove  92  may have the same or a different number of cutting implements  94 . In an embodiment, each groove  92  has four cutting implements  94  that are separate from each other. 
     In an embodiment, when two or more of the cutting implements  94  are positioned within a respective groove  92 , the two or more cutting implements  94  are substantially equally spaced from each other along a radially extending wall within each groove  92 . By “substantially equally spaced apart” it is meant that the distance or spacing between each of the cutting implements  94  along a length of the groove  92  is about the same. An example of this is shown in  FIG.  3 A  where cutting implements  94  that are of a square shape are each spaced about the same distance from each other within groove  92 . In other embodiments, the cutting implements  94  may not be equally spaced apart within the groove  94 . 
     In an embodiment, when there are two or more grooves  92 , the cutting implements  94  in each groove  92  may be radially offset from the cutting implements in another groove  92 . For example, the cutting implements  94  in each groove  92  may be offset from the center of the circular disc  90  by a different distance. An example of this is shown in  FIG.  4 B  where the cutting implement  94  closest to the center of the disc in each groove is positioned a different distance away from the center (as shown by A, B and C). By spacing identical cutting implements  94  at different distances from the center of the circular disc  90 , and then having the cutting implements  94  equally spaced apart within the groove  92 , this causes each cutting implement  94  to follow a different circular path upon rotation of the cutter head ( 22 ,  32 ). Thus, upon circular rotation, the two or more cutting implements  94  in each groove cuts a different circular area than the two or more cutting implements  94  in the other grooves. By “circular area” it is meant to refer to the area in the circular path of all of the cutting implements  94  within a respective groove. Since the cutting implements  94  are spaced apart, there would be alternating ‘cut’ and ‘cut’ paths for each groove  92 . In an embodiment, the cutting implements  94  in each groove can be arranged such the different circular area cut by the cutting implements  94  in each groove overlaps with a portion of the different circular area cut by the cutting implements  94  in at least one of the other grooves. This can be configured for any number of grooves  92  and any number of cutting implements  94  within each groove  92 . 
     The cutting implements  94  may be any suitable cutting device for milling a saw guide  50 . In an embodiment, the cutting implement  94  is a knife. In an embodiment, the cutting implements  94  are comprised of carbide. In an embodiment, the cutting implements  94  are approximately square or rectangle pieces of carbide. The cutting implements  94  may be secured to the circular disc  90  in any suitable manner. In an embodiment, the cutting implements  94  are secured to the circular disc  90  a screw or a clamp. In operation, each cutting implement  94  protrudes outwards from the grooves  92  by a sufficient amount to provide for milling of a saw guide  50  (see exemplary in  FIG.  4 C ). The angle of the wall of the groove may be adjusted to change the angle by which the cutting implement  94  contacts the saw guide  50 . 
     In an embodiment, the guide dresser  10  as disclosed herein comprises the cutter heads ( 22 ,  32 ) as disclosed herein. Combined usage of the guide dresser  10  and cutter heads ( 22 ,  32 ) of the present disclosure is advantageous in providing more accurate and reliable milling of saw guides  50 . 
     Referring now to  FIGS.  5 A and  5 B , in some embodiments one or both of the first cutter assembly  20  and the second head cutter assembly  30  may include a pivot component  100  for adjusting alignment of the respective cutter head ( 22 ,  32 ) in relation to a saw guide  50  to be milled. The pivot component  100  may be located on the underside of the cutter assembly ( 20 ,  30 ) and may be integral thereto or a separate component attached in some manner to the cutter assembly ( 20 ,  30 ). When equipped, the pivot component  100  is capable of allowing each cutter assembly to tilt independently in any direction to thereby adjust the alignment of the cutter heads ( 22 ,  32 ) in relation to a saw guide. Titling of the cutter heads ( 22 ,  32 ) can provide for more accurate and precise milling and machining of the saw guide. Since the cutter heads ( 22 ,  32 ) can tilt in any direction by way of the pivot component  100 , the pivot component  100  provides a means of spherical adjustment. 
     In an embodiment, the pivot component  100  of the cutter assembly ( 20 ,  30 ) allows for adjusting vertical alignment of the respective cutter head ( 22 ,  32 ). By “vertical alignment” it is meant to refer to the vertical plane of the cutter head ( 22 ,  32 ), which may be perfectly perpendicular to the plane of travel of the cutter assembly ( 20 ,  30 ) on the rail or slide system  12 , or may be slightly offset. In an embodiment, the vertical alignment is perfectly perpendicular to the plane of travel of the cutter assembly ( 20 ,  30 ). In an embodiment, the vertical alignment a straight up-down orientation. In some embodiments, the vertical alignment is offset from perpendicular to the plane of travel by about 0.1°, about 0.2°, about 0.3°, about 0.4°, about 0.5°, about 0.6°, about 0.7°, about 0.8°, about 0.9°, about 1.0°, about 1.25°, about 1.5°, about 1.75°, about 2.0°, about 2.25°, about 2.5°, about 2.75°, about 3.0°, about 3.5°, about 4.0°, about 4.5°, or about 5.0°. 
     In an embodiment, both the first cutter assembly  20  and the second cutter assembly  30  comprise a pivot component  100  for independently adjusting alignment of the respective cutter heads ( 22 ,  32 ). 
     In an embodiment, the pivot component  100  includes an upper part  102  and a lower part  104 . The upper part  102  and lower part  104  may be of any suitable configuration to allow pivotable movement therebetween. In an embodiment, the upper part  102  is shaped like a spherical plate having a curved bottom that rests within a cupped portion of the lower part  104  (e.g. a spherical plate atop a spherical cup). 
     With reference to  FIG.  6   , a further embodiment of a pivot component  100  is shown in which the upper part  102  and a lower part  104  each comprise a threaded bore  106  for receiving a bolt (not shown) to affix the upper part  102  to the cutter assembly ( 20 ,  30 ) and the lower part  104  to the slide or rail system  12  or a base that is slidably mounted to the rail or slide system  12 . Further, one or more convex caps  108  (e.g. protruding circular bumps) are provided on the shoulder of the cupped surface of the lower part  104  to facilitate the ease of pivotable adjustments. 
     Further suitable pivot components  100  for use in association with the guide dresser of the present disclosure may include a two-part pivotable block component, for example as disclosed in U.S. Pat. Nos. 9,199,320 and 10,267,450. 
     An exemplary two-part pivotable block component  110  that may be used in association with the cutter assembly ( 20 ,  30 ) of the present disclosure is shown in  FIG.  7   . The two-part block component  110  comprises an upper block  112  and a lower block  114 . The upper block  112  may be provided with threaded bores  111   a  aligned with bores  113   a  for receiving and engaging aligning bolts (not shown). Alternatively, the lower block may be provided with threaded bores for engaging aligning bolts inserted through bores provided therefore in the upper block. 
     The upper block  112  may be provided with a bore AA for receiving therethrough a post extending downward from the cutter assembly ( 20 ,  30 ). The upper block  112  has an outwardly inclined downward extending shoulder BB in the form of a frustoconical surface having a plane relative to a horizontal plane, selected from a range of between about 5° to about 75°, and more particularly between about 10° to about 45°. An exemplary suitable plane is about 10°, about 12.5°, about 15°, about 17.5°, about 20°, about 22.5°, about 25°, about 27.5°, about 30°, about 32.5°, about 35°, about 37.5°, about 40°, about 42.5°, about 45°, about 47.5°, or about 50°. 
     The lower block  114  may be provided with a bore CC that has a larger diameter than bore AA provided in upper block  112 . It is preferable that the diameter of bore CC provides a gap between the lower block  114  and a post extending therethrough, for example a gap of about 2 mm, about 3 mm, about 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, or anywhere therebetween. The lower block  114  has an inwardly receding inclined shoulder DD in the form of a frustoconical surface having a plane relative to the plane of the outwardly extending shoulder BB, that is offset to the plane of AA for example by about 0.25°, about 0.50°, about 0.75°, about 1.0°, about 1.25°, about 1.5°, about 1.75°, about 2.0°, about 2.25°, about 2.5°, about 2.75°, about 3.0°, about 3.5°, about 4.0°, about 4.5°, or about 5.0°. The offset in the planes between the outwardly inclined shoulder BB of upper block  112  and the inwardly receding inclined shoulder DD of lower block  114  enables precise pivotable adjustments of the cutter assembly ( 20 ,  30 ) in a three-dimensional space, and thereby alignment of the cutter head ( 22 ,  32 ). If so desired, one or more convex caps  116  may be provided on the upper shoulder BB or the lower shoulder DD (as shown in  FIG.  7   ) to facilitate the ease of pivotable adjustments of the two-part block component  110 . It is optional and within the scope of the present disclosure to provide the lower block  114  with an outwardly inclined upward extending shoulder, and to provide the upper block  112  with the inwardly receding inclined shoulder. 
     In other embodiments, the present disclosure relates to a method for milling a saw guide, the method comprising: moving a first cutter assembly  20  and a second cutter assembly  30  on a rail or slide system  12  to engage a first cutter head  22  of the first cutter assembly  20  and a second cutter head  32  of the second cutter assembly  30  against opposing sides of a stationary saw guide  50 ; and milling or machining the stationary saw guide  50 . 
     In an embodiment of the methods herein, the position of each cutter assembly ( 20 ,  30 ) on the rail or slide system  12  is controlled with programmable controller, such as a programmable logic controller (PLC) and/or computer numerical control (CNC) programming. In an embodiment, the rail or slide system  12  comprises its own independent motor to drive movement of each cutter assembly ( 20 ,  30 ) on the rail or slide system  12 . The motor may, for example, be a servo motor. In an embodiment, the rail or slide system  12  comprises servo motor-controlled ballscrew and linear bearings for programmable and repeatable positioning of each cutter assembly ( 20 ,  30 ). The rpm and spherical alignment of the cutter heads ( 22 ,  32 ) may also be similarly control by automated processes. 
     In an embodiment of the methods disclosed herein, milling of a saw guide  50  using the movable cutter assemblies ( 20 ,  30 ) and the cutter heads ( 22 ,  32 ) of the present disclosure is capable of cutting to high tolerances (e.g. cut to within 0.0005″). 
     In other embodiments, the present disclosure relates to a kit comprising one or more components of the cutter heads ( 22 ,  32 ) described herein. For example, in an embodiment, the present disclosure relates to a kit comprising a circular disc  60  for use as a cutter head ( 22 ,  32 ), and one or more removable knife retention apparatuses  70  as disclosed herein. The kit may further comprise one or more knives  80  for mounting in each of the removable knife retention apparatuses  70 . In another embodiment, the kit may comprise a circular disc  90  having two or more grooves  92  on a face thereof for use as a cutter head, and two or more cutting implements  94 . 
     In the present disclosure, all terms referred to in singular form are meant to encompass plural forms of the same. Likewise, all terms referred to in plural form are meant to encompass singular forms of the same. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. 
     As used herein, the term “about” refers to an approximately +/−10% variation from a given value. It is to be understood that such a variation is always included in any given value provided herein, whether or not it is specifically referred to. 
     It should be understood that the compositions and methods are described in terms of “comprising,” “containing,” or “including” various components or steps, the compositions and methods can also “consist essentially of or” consist of the various components and steps. Moreover, the indefinite articles “a” or “an,” as used in the claims, are defined herein to mean one or more than one of the element that it introduces. 
     For the sake of brevity, only certain ranges are explicitly disclosed herein. However, ranges from any lower limit may be combined with any upper limit to recite a range not explicitly recited, as well as, ranges from any lower limit may be combined with any other lower limit to recite a range not explicitly recited, in the same way, ranges from any upper limit may be combined with any other upper limit to recite a range not explicitly recited. Additionally, whenever a numerical range with a lower limit and an upper limit is disclosed, any number and any included range falling within the range are specifically disclosed. In particular, every range of values (of the form, “from about a to about b,” or, equivalently, “from approximately a to b,” or, equivalently, “from approximately a-b”) disclosed herein is to be understood to set forth every number and range encompassed within the broader range of values even if not explicitly recited. Thus, every point or individual value may serve as its own lower or upper limit combined with any other point or individual value or any other lower or upper limit, to recite a range not explicitly recited. 
     Therefore, the present disclosure is well adapted to attain the ends and advantages mentioned as well as those that are inherent therein. The particular embodiments disclosed above are illustrative only, as the present disclosure may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Although individual embodiments are dis-cussed, the disclosure covers all combinations of all those embodiments. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. Also, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee. It is therefore evident that the particular illustrative embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the present disclosure. If there is any conflict in the usages of a word or term in this specification and one or more patent(s) or other documents that may be referenced herein, the definitions that are consistent with this specification should be adopted. 
     Many obvious variations of the embodiments set out herein will suggest themselves to those skilled in the art in light of the present disclosure. Such obvious variations are within the full intended scope of the appended claims.