Abstract:
A runner for a snowmobile ski is fabricated from flat metal plate stock and incorporates mounting features for securing the runner to the ski and a wear strip of a relatively harder material provided on and projecting from a lower surface of the runner body. A quick release mounting system is provided for attaching the runner to the ski, including quick installation and release wedge mounting systems. The thin runner blade and wear strip are of the same thickness and are joined by a brazed joint. The invention contemplates a method of fabricating the runner and a method of mounting the runner.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a division of application Ser. No. 12/459,319 filed Jun. 30, 2009, now abandoned, which is a division of application Ser. No. 12/283,689 flied Sep. 15, 2008, now U.S. Pat. No. 7,614,627, which is a division of application Ser. No. 11/546,745 flied Oct. 13, 2006, now U.S. Pat. No. 7,497,447, which is a division of application Ser. No. 10/857,523 flied Jun. 1, 2004, now U.S. Pat. No. 7,185,897. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Technical Field 
     This invention relates generally to replaceable runners for snowmobile skis, and method of making same more particularly to the mounting of such runners on the ski. 
     2. Related Art 
       FIG. 1  is a cross sectional end view of a conventional snow ski outfitted with a typical wear bar or runner that is used to enhance the traction of the snow ski, particularly on icy terrain. The conventional runner includes an elongated runner body fabricated of cast steel rod that extends between opposite ends. A pair of threaded studs are welded to the top surface of the runner body and extend through associated openings in the ski. Nuts are threaded onto the exposed upper ends of the threaded studs and are tightened to draw the upper surface of the runner body tightly against the underside of the ski to secure the runner rigidly, but removably, in place. A slot is cut in a lower surface of the runner body and a carbide wear strip is brazed therein. The carbide wear strip presents an exposed lower running surface for engaging a terrain and enhancing the traction and thus steerability of the skis, particularly on icy or packed snow conditions. While such runners are effective at enhancing the steerability of the skis, they are rather bulky and take time to replace, particularly if the threads of the mounting studs become corroded, making removal of the nut difficult. Moreover, the runners are prone to loosening due to constant vibration and stress placed on the mounting system causing the nuts to unthread over time. 
     It is an object of the present invention to improve upon runner systems for snowmobile skis and to simplify the construction and mounting of such runner systems. 
     SUMMARY OF THE INVENTION AND ADVANTAGES 
     A runner constructed according to one aspect in the invention is mountable on a ski of an ice-going vehicle and comprises an elongate runner body fabricated of a first material having longitudinally opposite ends, an upper surface and a lower surface. At least two mounting members extend from the upper surface of the runner body. A wear strip, fabricated of a second material relatively harder than that of the first material, projects from the lower surface of the runner body and presents an exposed ice-engaging runner body surface. According to the invention, the runner body and the at least two mounting members are fabricated of a single piece of flat metal plate of the first material. 
     The invention has the advantage of providing a runner in which the runner body and mounting members are fabricated of the same material and further which have a flat plate construction, thereby minimizing the weight of the overall runner and simplifying the construction of the runner. Unlike the prior art runners in which the mounting members are separately fabricated from the runner body and then joined by a separate brazing or welding operation in the typical form of a threaded cylindrical stud, the present invention has the advantage of incorporating the manufacture of the mounting members in with the manufacture of the runner body, thereby simplifying the construction and manufacture of the runner. 
     According to a further aspect of the invention, an improved mounting system is provided for readily mounting and unmounting the runner to and from a snow ski. In particular, the mounting members are formed with a wedge-engaging surface which is preferably arranged transverse to the longitudinal direction of the mounting members. The wedging surfaces are operative to interact with a wedge connection that acts between the wedging surface and the snow ski to forceably draw the mounting members through associated openings in the ski, bringing an upper surface of the runner body tightly against an underside of the snow ski. This wedging approach to mounting the runner body is to be used in place of the traditional threaded stud and nut-type mounting system of conventions runners and is less prone to loosening when subjected to stress and vibration during use. In addition, the wedge-type mounting system provides a convenient quick-release feature to the runner, enabling a user to quickly and conveniently mount and dismount the runner which is advantageous, particularly in competitive snowmobile racing conditions where time is crucial. 
     According to another aspect in the invention, a snowmobile ski assembly is provided having a longitudinally extending ski with an upper and lower surface and at least two longitudinally spaced runner openings extending between the surfaces. A runner is provided having a runner body extending longitudinally between opposite ends and having an upper surface and a lower surface. At least two mounting members extend from the upper surface of the runner body and are spaced longitudinally from one another at a distance to enable the mounting members to be extended through the runner openings from the lower surface of the ski. A hard wear strip which may comprise carbide, projects from a lower surface of the runner and provides an ice-engaging running surface to enhance traction. According to the invention, the mounting members comprise flat portions which are simple to make and weigh less than the traditional threaded stud mounting members of prior art runners. The flat portion mounting members further are readily adaptable to the wedge lock mounting system described above and thus shares the same advantages. 
     According to a further aspect of the invention, a method of fabricating a runner of the type described is provided and includes the stamping of the runner body from a thin flat plate of metal with mounting features which facilitate quick coupling and decoupling to and from the underside of a snowmobile ski. In one configuration, the mounting features are formed by concurrently stamping transverse wedge openings in the runner body. In another configuration, the mounting features are formed by concurrently stamping mounting members which are integral with the upper surface of the runner body. The method contemplates the concurrent stamping of wedging surfaces that comprise wedge holes or notches extending through the mounting members. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features and advantages of the present invention will become more readily appreciated when considered in connection with the following detailed description and appended drawings, wherein: 
         FIG. 1  is a front end cross-sectional view representative of a prior art snowmobile ski and runner assembly; 
         FIG. 2  is a front end cross-sectional view of a snowmobile ski and runner assembly constructed according to a first embodiment of the present invention; 
         FIG. 3  is a side elevation view of a runner constructed according to a first embodiment to the invention and mounted in the assembly illustrated in  FIG. 2 ; 
         FIG. 4  is an enlarged rear cross-sectional view taken along the section line  4 - 4  of  FIG. 3 ; 
         FIG. 5  is a side cross-sectional view taken generally along the section line  5 - 5  of  FIG. 2 ; 
         FIGS. 6-7  are greatly enlarged fragmentary cross-sectional end views, similar to  FIG. 2 , but illustrating the steps involved in installing the runner in position on the ski; 
         FIG. 8  is fragmentary cross-sectional end view, similar to  FIGS. 6 and 7 , illustrating a final installation step; 
         FIG. 9  is a greatly enlarged top cross-sectional view, taken along the line  9 - 9  of  FIG. 8 ; 
         FIG. 10  is a front end cross-sectional view of a snow ski and runner constructed according to a second embodiment of the invention; 
         FIG. 11  is a front end cross-sectional view of a snow ski and runner assembly constructed according to a third embodiment of the invention; 
         FIG. 12  is a cross-sectional side view taken generally along section line  12 - 12  of  FIG. 11 ; 
         FIGS. 13-14  are fragmentary sectional side views of a snow ski and runner assembly, constructed according to a fourth embodiment of the invention, illustrating sequential steps of installation; 
         FIGS. 15-19  are enlarged front cross-sectional end views taken through carbide receiving slot of the runner body illustrated in  FIG. 3 , illustrating successive steps in the manufacture of a runner according to the invention; 
         FIG. 20  is a front end cross-sectional view of a snowmobile ski and runner assembly constructed according to a fifth embodiment of the invention; 
         FIG. 21  is a front end cross-sectional view of a snow ski and runner assembly constructed according to a sixth embodiment of the present invention; 
         FIG. 22  is a greatly enlarged sectional side view, taken along the line  22 - 22  of  FIG. 21 ; 
         FIG. 23  is a bottom view, taken along the line  23 - 23  of  FIG. 24  illustrating the initial stamping or die cutting of the blank utilized to form the runner body illustrated in  FIGS. 21 and 22 ; 
         FIG. 24  is a sectional end view, taken along the section line  24 - 24  of  FIG. 23  illustrating the footprint in a planar position; 
         FIG. 25  is an end elevational view illustrating a subsequent step of the manufacture with the wings in the folded position illustrated in phantom lines; 
         FIG. 26  is an end elevational view illustrating the folded runner body in an inverted position in which time the carbide wear bar is brazed into a socket formed in a base of the runner body; 
         FIG. 27  is an end elevational view after the brazing of the wear bar has been completed; 
         FIG. 28  is a side sectional view, taken along the section line  28 - 28  of  FIG. 27 ; and 
         FIG. 29  is a bottom view, taken along the line  29 - 29  of  FIG. 27 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A traction increasing wear bar or runner constructed according to a first presently preferred embodiment of the invention, as indicated generally at  10  in  FIGS. 3 and 4 , shown mounted on a snowmobile ski  12  in FIGS.  2  and  5 - 9 . The ski  12  includes a ski runner  11 , which may be fabricated from plastic material, having a vertically depressed, centrally disposed, elongate keel  13  provided with opposed side walls  15 . 
     The runner  10  includes a runner body  14  which is fabricated as a single piece, stamped, die cut or otherwise totally concurrently cut from a flat sheet or plate of metal stock of a first material, such as steel or aluminum-based metals. The runner body  14  extends longitudinally between opposite ends  16 ,  18  and has an upper surface  20 , a lower surface  22  and opposed lateral side surfaces  23  extending therebetween. The runner  10  includes mounting features associated with the runner body  14  which are concurrently stamped and operate to mount the runner  10  to the ski  12  in a manner to be described in greater detail below. According to the first embodiment, the mounting features are in the preferred form of at least a pair of mounting members  24  projecting from and integral with the upper surface  20  of the runner body  14 . ( FIG. 3 ). The mounting members  24  are preferably fabricated of the same sheet stock material as that used to form the runner body  14  and are preferably concurrently stamped or die cut at one time and as one piece with the runner body such that the mounting features are incorporated into the one piece construction of the runner body  14 . The mounting members  24  thus have a flat plate construction and extend transverse to the longitudinal axis of the runner body  14 . The mounting members  24  are spaced longitudinally from one another by a distance corresponding to an associated set of longitudinally spaced ski runner openings  26 , formed in the ski  12 , as illustrated best in  FIG. 5 . The ski runner openings  26  may have a slot-shaped configuration corresponding generally to the cross-sectional size and shape of the mounting members  24  or, as illustrated in FIGS.  2  and  5 - 9 , with particular emphases on  FIGS. 5 and 9 , the runner openings  26  may have a generally cylindrical shape with the width of the mounting members  24  being sized to engage or be spaced slightly from the walls of the runner openings  26  as shown in  FIGS. 5 and 9  such that the walls of the runner openings provide both for and aft and side to side support to the mounting members despite being circular in cross-section rather than rectangular. As such, the flat plate mounting member feature can be readily adapted as a retrofit to existing snowmobile skis  12  fitted with cylindrical runner openings  26  that previously would have been used to receive cylindrical threaded mounting studs of prior art runners, such as that shown representatively in  FIG. 1  described in the background. The mounting members  24  are preferably free of screw thread features. 
     A wear strip  28  is joined to the lower surface  22  of the runner body  14 . The wear strip  28  is fabricated of a second material, such as a carbide material, which is relatively harder and thus more wear resistant than that of the first material of the runner body  14 . For example, the wear strip  28  can be fabricated of a hard carbide material, whereas the runner body  14  can be fabricated of an aluminum-based material of lesser hardness. The runner body  14  is preferably formed with a wear strip notch  30  that is recessed in the lower surface and which is spaced from the ends  16 ,  18  but extends fully across the entire width of the runner body  14  so as to be open to the opposing side surfaces  23  of the runner body. The wear strip  28  preferably has a width or thickness corresponding to that of the runner body  14  and a length corresponding to that of the notch  30 . The height of the wear strip  28  exceeds the depth of the notch  30  such that the wear strip  28  projects downwardly from the lower surface  22  of the runner body  14  to present an exposed ice-engaging runner surface for engaging the terrain on which the ski  12  runs, such as on ice or snow-packed conditions. As illustrated in  FIGS. 2 ,  8  and  10  the runner body  14 , mounting members  24 , and wear strip  28  lie in the same vertical plane P. As illustrated in  FIG. 9 , the transverse thickness T of the runner body  14  and mounting members  24  is uniform and substantially equal throughout. 
     With reference to  FIGS. 15-19 , a process is provided for joining the wear strip  28  to the runner body  14 . As mentioned, the invention contemplates using an aluminum-based material for the runner body which presents challenges since aluminum is prone to forming a very tough, stable oxide on its surface which is resistant to forming a metallurgical bond with another material at the interface as the oxide serves as a barrier to the intermixing of metals. The invention provides one technique for addressing and overcoming the challenges of joining the wear strip  28  to an aluminum runner body  14 , which could equally be used when materials other than aluminum are used for the runner body, such as steel. As shown in  FIGS. 15-18 , the method involves inverting the runner  10  such that the lower surface  22  of the runner body  14  is facing upwardly. When so positioned, a flux agent  34  is introduced to the notch  30  ( FIG. 16 ). The flux agent  34  is one chosen to interact favorable during joining to break up any oxides or other impurities or impediments to promote the formation of a metallic bond at the interface of the materials to be joined. In the preferred method, a strip  36  of brazing material is laid in the notch  30  overtop the fluxing agent  34 , as illustrated in  FIG. 17 . The wear strip  28  is then placed in the notch  30  atop of the strip of braze material- 36 , as shown in  FIG. 18 , and the pre-joined assembly of components is supported by relatively positioning the components and a guide  38  so that the guide  38  is at least partially around the components to hold them in position during joining. The guide  38  is shown in  FIG. 19  and preferably comprises a block of electrically non-conductive material, such as a ceramic material. The guide  38  is formed with a downwardly opening recess  40  that compliments the shape of the assembled components such that the walls of the recess engage and support the wear strip  28  in alignment with the runner body  14  during joining. Brazing is carried out preferably by induction heating. As shown schematically in  FIG. 19 , the assembled wear strip  28 , runner body  14  and guide  38  are placed in the presence of an induction heating field  42  which passes through the guide  38  and reacts at the interface to heat the runner body  14 , flux agent  34 , braze material  36  and wear strip  28  but without heating the guide  38 . On heating, the flux agent  34  reacts with the runner body  14  to break up any oxides on its surface simultaneously or near simultaneously with the melting of the brazed material  36  which then interacts with the surfaces of the runner body  14  and wear strip  28  to form, upon cooling, a metallic braze joint therebetween. When brazing of the strip  28  to the runner body  14  is completed, the entire assembly may be deposited into a quenching liquid such as oil to thru harden the runner body  14  to increased hardness (if the runner body  14  is steel) which is still less than the hardness of the carbide wear strip  28 . The quenching liquid preferably has a quenching rate of reducing the temperature of the product 600° F. per minute. Other quenching mediums include molten salt baths, polymers, etc. 
     Turning back to  FIGS. 2 through 9 , the means for mounting the runner  10  on the ski  12  according to the invention will now be described in connection with the first embodiment. As illustrated in  FIGS. 3 and 5 , the mounting members  24  are formed with wedge-engaging surfaces  44 , in the preferred form of mounting holes, provided adjacent the free ends of the mounting members  24 . To mount the runner  10  on the ski  12 , the free ends of the mounting members  24  are extended into the ski runner openings  26  from the lower surface  68  of the ski  12 . The ski  12  is preferably formed to include a pair of laterally spaced mounting blocks  46  mounted atop the ski  12  and defining an opening communicating with the runner openings  26  in position to receive the upper free ends of the mounting members  24  as they are extended through the ski runner openings  26 . The lateral spacing between the adjacent mounting blocks is sufficient to accommodate the introduction of the mounting members  24  and can be either a snug or loose fit with respect to the lateral thickness or width of the mounting members, but is preferably slightly greater in spacing than the thickness of the mounting members  24 . As shown best in  FIG. 6 , the mounting blocks  46  are formed with a cross-bore  48  for receiving a fastener  50  as described below. The fastener or coupling bolt  50  has a reduced diameter threaded end  52  with a conical shaped terminal end  54 . The threaded end section  52  transitions to an enlarged diameter unthreaded shank section  56  via an intermediate frustoconical shaped camming surface or ramp  58 . A bolt head  60  is secured to the free end of the shank  56 . The cross-bore  48  of the mounting blocks  46  has a shape complimenting that of the fastener  50  and includes a threaded section  62  and an adjoining frustoconical camming surface  64  provided on one half of the mounting blocks  46 , and an enlarged shank bore  66  provided on the other of the mounting blocks. If the mounting blocks  46  are formed of yieldable plastic material, the threaded sections  62  may comprises an internally threaded metal fastener, such as a T-nut. 
     The mounting hole  44  of the mounting members  24  is positioned along the mounting members  24 , such that when a user inserts the mounting members  24  the runner body  14  by hand into the runner openings  26  and extends the runner body  14  to the point where its upper surface  20  closely approaches a lower surface  68  of the ski  12 , there is a slight misalignment between the holes  44  and the mounting members  24  and the cross-bore  48  in the mounting blocks, such that the axis of the mounting holes  44  is slightly below the axis of the cross-bore  48 . According to the invention, there is a wedging action which occurs between the fastener  50 , the cross-bore  48  and the mounting holes  44  which acts to bring the axis of the holes into alignment and to urge the runner body  14  further upwardly into tight, stable engagement with the underside  68  of the ski to hold the runner firmly in place during operation. As the upper surface  20  engages the underside of the ski runner keel  13 , any undulations on the underside of the plastic material in the ski runner keel may slightly yield and compress under the force of the wedging action to facilitate the final upward positioning of the runner body  12 , with a preload, in tight clamping relation with the ski keel  13 . As illustrated in  FIG. 7 , the threaded section  62  of the fasteners  50  are guided through the shank bores  66 , mounting holes  44  and camming surface  64  into the threaded section  62 , whereupon turning the fasteners  50  to tighten it brings the camming surface  58  of the fasteners  50  into engagement with the upper edge of the mounting holes  44  of the runner body  14 . Further advancement of the fasteners  50  causes the mounting members  24 , and thus the runner body  14 , to cam upwardly across the camming surface  64 , whereupon the upper surface  20  of the runner body  14  is urged more and more into tight engagement with the lower surface  68  of the ski, until such point as the fastener  50  is advanced to where the unthreaded shank section  56  enters the mounting hole  44 , as illustrated in  FIGS. 2 ,  5  and  8 . In this manner, the runner  10  is firmly locked to the ski  12 , but yet is readily removable for replacement by simply unthreading the fastener  50  and inserting a pry tool, such as a screwdriver (not shown) in one of both notches  70  and to apply a downward prying force to withdraw the mounting members  24  from the runner openings  26 . 
     Alternate Embodiment 
       FIG. 10  illustrates an alternative embodiment of the invention wherein the same reference numerals are used to represent the same or like features, but are offset by  100 . The runner  110  is constructed identically to that of the runner  10  of the first embodiment. The mounting blocks  146  differ in that the cross-bores  148  are simply a straight bore of uniform diameter corresponding closely to that of the diameter of the mounting holes  144  of the runner  110 . A simple fastener  150  with a bolt head  160  and threaded end section  152  is passed through the cross-bore  148  and mounting hole  144  without any wedging action and is secured by a nut  72 . 
     Third Alternate Embodiment 
       FIGS. 11 and 12  illustrate a snowmobile ski and runner assembly constructed according to a third embodiment of the invention, wherein the same reference numerals are used to indicate the same or like features as that of the first embodiment, but are offset by  200 . In this embodiment, the runner body  214  lacks the projecting mounting members  24  employed in the first embodiment, and instead provides at least two and preferably at least three mounting holes  244  formed in the runner body  214  at locations between the ends  216 ,  218  and between the upper and lower surfaces  220 ,  222 . The wear strip  228  is formed and joined to the underside of runner body  214  in the same manner as that described in connection with the first embodiment. The ski  212  has its runner opening  226  ( FIG. 11 ) provided in the keel  213  form of an elongated vertical channel or slot  74  which is opened to the lower surface  268  of the ski  212 , but is closed at least in part to the upper surface thereof such that the runner  210  does not extend above the upper surface of the ski  212 . The keel  213  is formed with a plurality of cross-bores  76  which intersect the slot  74  in alignment with the mounting holes  244  of the runner body  214 . A fastener  78  is introduced into each cross-bore  76  and extends through the mounting holes  244  and is secured by an associated nut  80  for securing the runner  210  to the ski  212 . The invention contemplates that the cross-bore  76  can be configured to correspond to that of the cross-bore  48  of the first embodiment and the fastener  78  configured to correspond to that of the fastener  50  to provide wedging engagement of the runner  210  within the slot  74  of the ski  212  wherein an upper surface of the runner  210  would be urged under the camming action firmly against the upper base wall of the slot  74 . Depending on the thickness of the walls of the keel  213 , the squeezing force exerted by the relative turning of the bolt  78  and the nut  80 , the keel walls  215  can be compressed against opposite sides of the runner body  214 . 
     Fourth Alternate Embodiment 
       FIGS. 13 and 14  illustrate yet a fourth embodiment of the invention, wherein the same reference numerals are used to indicate the same or like features, but are offset by  300 . The runner  310  has a runner body  314  and mounting members  324  projecting from an upper surface  320  of the runner body  314 . The wedge-engaging surface  334  is in the form of a camming notch  82  formed in at least one and preferably all of the mounting members  324 , as illustrated best in  FIG. 13 . The camming notches  82  are preferably formed at the base of the mounting members  324  and taper inwardly to a point deepest at the base. The ski  312  is formed with runner openings  326  associated with the mounting members  324 . The runner openings  326  are oversized in relation to the width of the mounting members  24  one edge of each runner opening  326  is formed with a camming surface  84 . The mounting members  324  are initially introduced through the runner openings  326  with the camming notch  82  spaced longitudinally from the camming surfaces  84 , as illustrated in  FIG. 13 . The runner body  314  is then forceably slid longitudinally relative to the ski  312  by application of a force F applied to the runner  310  such as by a sharp blow from a hammer, to forceably urge the camming notches  82  into camming engagement with the camming surfaces  84  of the openings to drive the runner  310  further upwardly, bringing the upper surface  320  of the runner body  314  tightly against the lower surface  368  of the ski  312 . 
     As shown in  FIG. 13 , at least one of the mounting members  324  is formed with a retaining hole  86  which is initially misaligned with a corresponding retaining hole  88  formed in the ski. However, when the runner  310  is forced to the tightly wedged installed position of  FIG. 14 , the holes  86 ,  88  align, enabling a pin  90  to be installed therein to retain the runner  310  in position on the ski  312  against inadvertent loosening. To remove the runner  310 , the user simply pulls the pin  90  and then strikes the runner  310  with a hammer in the opposite direction to drive the camming notches  82  out of engagement with the camming surface  84  as in  FIG. 13 , allowing the runner  310  to be disassembled from the ski  312  and replaced. 
     Fifth Alternate Embodiment 
       FIG. 20  illustrates a further embodiment of the invention which, essentially is like the embodiment of  FIGS. 11 and 12 , except that instead of just a single runner  214 , there is provided a plurality of such laterally spaced longitudinally extending runners  214 , with two being shown. The keel  213  of the ski is formed with a corresponding plurality of laterally spaced apart, longitudinally extending grooves, channels or slots  74  in which the runners  214  are received. The fasteners  78  extend through the aligned openings  244  in the runners  214  and pass transversely through the slots  74  for securing the runners  214  releasably on the ski. The runners  214  are preferably identically constructed and thus interchangeable. The runners  214  are preferably discrete, separate structures that, when mounted, are spaced laterally from one another. If desired, the runner  214  may be of different lengths and/or may be longitudinally staggered. 
     Sixth Alternate Embodiment 
       FIGS. 21-22  and  27 - 29  illustrate yet a sixth embodiment of the invention wherein the same reference numerals are used to indicate the same or like features but are offset by  400 . The ski  412  and the keel  413  differ from the ski  12  and keel  13  in that the ski  412  and the keel are more flexible throughout their lengths to more closely follow any undulations in the underlying terrain being traversed. The ski  412  may be much thinner than the ski  12  and the keel  413  is much narrower than the keel  13  and does not include a downwardly opening slot therein or vertically extending therethrough. 
     As illustrated in  FIG. 22 , the runner  410 , rather than including a one piece runner body  14 , includes a plurality of longitudinally spaced apart, discrete, separate runner body segments, generally designated  99 . Each runner body segment  99  includes a runner body  414  which is fabricated as a single piece that is stamped or die cut in its entirety from a flat sheet or plate of metal stock, such as aluminum or steel. The stock material is of uniform thickness T ( FIG. 24 ) in the range of 3/16″ thick. The runner body  414  has a U-shape when longitudinally viewed, ( FIGS. 21 and 27 ) and includes an elongate central base  91  having laterally outer edges  91 A integrally coupled to the laterally inner edges  93 A of laterally spaced apart upstanding wings, legs or plates  93 . The plates  93  have aligned transverse mounting aperture  444  therethrough for pivotally receiving a pivotal coupling pin  478  when the holes  444  are aligned with a cross bore  476  in the keel  413 . The holes  444  and the cross bore  476  or each segment  93  are aligned with the holes  444  when the runner body segments  99  are mounted on the underside of the ski  412  as illustrated in  FIG. 22 . 
     The legs  93 , as laterally viewed in  FIGS. 22 and 28 , have a trapezoidal or truncated triangle shape. Each wing or leg  93  includes a laterally inner edge  93 A integrally coupled to one of the laterally outer edge portions  91 A of the base  91  and a laterally outer edge  95  disposed parallel to the laterally inner edges  93 A. 
     Each upwardly disposed wing, plate or leg  93  includes downwardly converging longitudinally spaced, forward and rearward sides or end edges  93 C and  93 D, respectively, which provide a clearance or spacing, generally designated by the arrow  94  between the adjacent segments  99 . This spacing allows each runner body  414 , when the ski  412  and keel  413  vertically flex or undulate along their lengths, to conform to the underlying terrain, and swing, in a to-and-fro path about the axis of one of the pins  478 , represented by the directions of the arrows  95  and  96 . 
     A hardened carbide strip  428  is disposed in a slot  430  which is stamped cut or machined in the underside of the base  91 . The strip  428  is then brazed or otherwise suitably coupled to the underside of the base  91  of each runner body segment  414 . 
     The lengths L and L 1  of the laterally inner and outer parallel edges  91 A and  95 , respectively, may typically be in the range of 2-2½″ and 3-3½″, respectively. The slot  430  has a width typically in the range of 3/16 to ½ inch and a depth of approximately ½ of the thickness T of runner body  414 . 
     As illustrated in  FIG. 28 , the wings and/or walls  93  include longitudinally spaced forward and rear edges  93 C and  93 D, respectively, which longitudinally diverge outwardly away from the base  91  in a direction toward the outer edge  95 . As illustrated in  FIG. 28 , when the wines  93  are folded upwardly, to the positions illustrated in  FIGS. 27 and 28 , longitudinally opposite ends  95  and  96  of the carbide wear bar  428 , also upwardly diverge and are disposed flush with the longitudinally spaced end edges or surfaces  93 C and  93 D, respectively. 
       FIGS. 23-27  illustrate successive steps in the manufacture of the runner  410  which includes a plurality of longitudinally aligned, longitudinally spaced runner bodies  414 . Each runner body  414  is stamped or die cut from a flat sheet of metal in the shape illustrated in  FIG. 23  that is sometimes referred to as a “footprint” and may be generally classified as having an “hour glass” or “bow tie” shape. The runner body  414  includes the central base section  91  having laterally opposite edges  91 A and  91 B integrally coupled at the fold lines F and F 1 , respectively, to the laterally inner edges  93 A of the pair of laterally outwardly extending legs  93 . The stamped out footprint illustrated in  FIG. 23  includes the wings  93  each in the form or shape of a trapezoid or truncated triangle having a laterally inner edge  93 A of a predetermined length L and a laterally outer terminal parallel edge  95  which has a length L 1  which is substantially greater than the length of the laterally inner wing edge  93 A. As illustrated in  FIG. 24 , when the hour glass shape is cut, a notch  430  is concurrently stamped into the underside of the central base section  91 . During the stamping operation, a mounting hole  444  is concurrently cut into each of the wings  93 . The wings  93  are then folded or rolled upwardly and inwardly, in the opposite direction represented by the arrows X and Y to the final positions illustrated in chain lines in  FIG. 24  and in solid lines in  FIG. 25 . The runner  410  is then inverted to the position illustrated in  FIG. 26  and a flux agent  434  and brazing material  436  are deposited into the slot  430  and the hardened wear strip  428  is deposited therein. The assembly is placed into an induction heater where brazing occurs as was previously described with regard to  FIGS. 2-9  so that the runner body is now in its finished position as illustrated in  FIG. 27 . The heated and brazed construction may be deposited into a quenching bath to harden the runner body  444 . 
     When the footprint of the runner body  414  is die cut as illustrated in  FIG. 23 , the holes  444  are concurrently cut and the slot  24  in the carbide wear strip is concurrently punched to form a slight elongate ridge R open the top surface of the base  91 . If desired, the ridge R can be removed via machining. Alternatively, the slot  24  may be machined into the undersurface to eliminate the formation of ridge R. 
     It is to be understood that the drawings and descriptive matter are in all cases to be interpreted as merely illustrative of the principles of the invention, rather than as limiting the same in any way, since it is contemplated that various changes may be made in various elements to achieve like results without departing from the spirit of the invention or the scope of the appended claims.