Patent Publication Number: US-8534767-B2

Title: Manually rotatable tool

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 12/428,531, filed Apr. 23, 2009, which is a continuation-in-part of U.S. patent application Ser. No. 12/177,556, filed Jul. 22, 2008, now U.S. Pat. No. 7,635,168 which is a continuation-in-part of U.S. patent Ser. No. 12/135,595, filed Jun. 9, 2008, now U.S. Pat. No. 7,946,656 which is a continuation-in-part of U.S. patent Ser. No. 12/112,743, filed Apr. 30, 2008, now U.S. Pat. No. 8,029,068 which is a continuation-in-part of U.S. patent application Ser. No. 12/051,738, filed Mar. 19, 2008, now U.S. Pat. No. 7,669,674 which is a continuation-in-part of U.S. patent application Ser. No. 12/051,689, filed Mar. 19, 2008, now U.S. Pat. No. 7,963,617 which is a continuation of U.S. patent application Ser. No. 12/051,586, filed Mar. 19, 2008, now U.S. Pat. No. 8,007,050 which is a continuation-in-part of U.S. patent application Ser. No. 12/021,051, filed Mar. 19, 2008, now U.S. Pat. No. 8,123,302 which is a continuation-in-part of U.S. patent application Ser. No. 12/021,019, filed Jan. 28, 2008, which was a continuation-in-part of U.S. patent application Ser. No. 11/971,965, filed Jan. 10, 2008, now U.S. Pat. No. 7,648,210 which is a continuation of U.S. patent application Ser. No. 11/947,644, filed Nov. 29, 2007, now U.S. Pat. No. 8,007,051 which was a continuation-in-part of U.S. patent application Ser. No. 11/844,586, filed Aug. 24, 2007, now U.S. Pat. No. 7,600,823. U.S. patent application Ser. No. 11/844,586 is a continuation-in-part of U.S. patent application Ser. No. 11/829,761, filed Jul. 27, 2007, now U.S. Pat. No. 7,722,127. U.S. patent application Ser. No. 11/829,761 is a continuation-in-part of U.S. patent application Ser. No. 11/773,271, filed Jul. 3, 2007, now U.S. Pat. No. 7,997,661. U.S. patent application Ser. No. 11/773,271 is a continuation-in-part of U.S. patent application Ser. No. 11/766,903, filed Jun. 22, 2007. U.S. patent application Ser. No. 11/766,903 is a continuation of U.S. patent application Ser. No. 11/766,865, filed Jun. 22, 2007, now abandoned. U.S. patent application Ser. No. 11/766,865 is a continuation-in-part of U.S. patent application Ser. No. 11/742,304, filed Apr. 30, 2007, now U.S. Pat. No. 7,475,948. U.S. patent application Ser. No. 11/742,304 is a continuation of U.S. patent application Ser. No. 11/742,261, filed Apr. 30, 2007, now U.S. Pat. No. 7,469,971. U.S. patent application Ser. No. 11/742,261 is a continuation-in-part of U.S. patent application Ser. No. 11/464,008, filed Aug. 11, 2006, now U.S. Pat. No. 7,338,135. U.S. patent application Ser. No. 11/464,008 is a continuation-in-part of U.S. patent application Ser. No. 11/463,998, filed Aug. 11, 2006, now U.S. Pat. No. 7,384,105. U.S. patent application Ser. No. 11/463,998 is a continuation-in-part of U.S. patent application Ser. No. 11/463,990, filed Aug. 11, 2006, now U.S. Pat. No. 7,320,505. U.S. patent application Ser. No. 11/463,990 is a continuation-in-part of U.S. patent application Ser. No. 11/463,975, filed Aug. 11, 2006, now U.S. Pat. No. 7,445,294. U.S. patent application Ser. No. 11/463,975 is a continuation-in-part of U.S. patent application Ser. No. 11/463,962, filed Aug. 11, 2006, now U.S. Pat. No. 7,413,256. The present application is also a continuation-in-part of U.S. patent application Ser. No. 11/695,672, filed Apr. 3, 2007, now U.S. Pat. No. 7,396,086. U.S. patent application Ser. No. 11/695,672 is a continuation-in-part of U.S. patent application Ser. No. 11/686,831, filed Mar. 15, 2007, now U.S. Pat. No. 7,568,770. All of these applications are herein incorporated by reference for all that they contain. 
    
    
     BACKGROUND OF THE INVENTION 
     Formation degradation, such as drilling to form a well bore in the earth, pavement milling, mining, and/or excavating, may be performed using degradation assemblies. In normal use, these assemblies and auxiliary equipment are subjected to high impact, heat, abrasion, and other environmental factors that wear their mechanical components. Many efforts have been made to improve the service life of these assemblies. In some cases it is believed that the free rotation of the impact tip of the degradation assembly aides in lengthening the life of the degradation assembly by promoting even wear of the assembly. 
     U.S. Pat. No. 5,261,499 to Grubb, which is herein incorporated by reference for all that it contains, discloses a two-piece rotatable cutting bit which comprises a shank and a nose. The shank has an axially forwardly projecting protrusion which carries a resilient spring clip. The protrusion and spring clip are received within a recess in the nose to rotatable attach the nose to the shank. 
     U.S. patent application Ser. No. 12/177,556 to Hall, et al., which is herein incorporated by reference for all that it contains discloses, a degradation assembly comprises a shank with a forward end and a rearward end, the rearward end being adapted for attachment to a driving mechanism, with a shield rotatably attached to the forward end of the shank. The shield comprises an underside adapted for rotatable attachment to the shank and an impact tip disposed on an end opposing the underside. A seal is disposed intermediate the shield and the shank. 
     BRIEF SUMMARY OF THE INVENTION 
     In one aspect of the present invention, a tool assembly comprises a rotary portion and a stationary portion. The rotary portion comprises a bolster bonded to a diamond, symmetric, substantially conically shaped tip. The stationary portion comprises a block mounted to a driving mechanism. A compressible element is disposed intermediate and in mechanical contact with both the rotary and stationary portions. The compressible element is compressed sufficiently to restrict free rotation during a degradation operation. In some embodiments, the compressible element is compressed sufficiently enough to prevent free rotation. The tool assembly may be a degradation assembly. 
     In some embodiments, the compressible element comprises an o-ring under 20%-40% compression. The o-ring may also comprise a hardness of 70-90 durometers. The compression element may also act as a seal that retains lubricant within the assembly. The compression element may comprise any of the following: at least one rubber ball, a compression spring, a set screw, a non-round spring clip, a spring clip with at least one flat surface, a press fit pin, or any combination thereof. A first rubber compressible element may be disposed on the stationary portion and be in contact with a second rubber compressible element disposed on the rotary portion. 
     In some embodiments, the rotary portion of the assembly may comprise a puller attachment and/or a wrench flat. The rotary portion may also comprise a shield, such that a recess of the shield is rotatably connected to a first end of the stationary portion. The bolster may also wrap around a portion of the stationary portion. 
     In some embodiments, the compressible element may comprise a metallic material. The compressible element may be part of a metal seal, which is tight enough to prevent restrict or prevent free rotation. 
     In another aspect of the present invention the assembly may comprise a holder. The holder may be part of either the stationary or the rotary portion of the assembly. The holder may comprise at least on longitudinal slot. 
     In one aspect of the present invention, a degradation assembly comprises a bolster intermediate a shank and a symmetric, substantially conical shaped tip. The tip comprises a substrate bonded to a diamond material. The diamond comprises an apex coaxial with the tip, and the diamond being over 0.100 inches thick along the central axis of the tip. The shank is inserted into a holder attached to a driving mechanism. The assembly comprises a mechanical indexing arrangement, wherein the tip comprises a definite number of azimuthal positions determined by the mechanical indexing arrangement, each position orienting a different azimuth of the tip such that the different azimuth impacts first during an operation. 
     In some embodiments, the shank comprises substantially symmetric longitudinal flat surfaces. The shank may axially comprise a hexagonal shape, a star shape, or any other axially symmetric shapes. The shank may comprise and o-ring, a catch, a spring clip, or any combination thereof. The tip may be rotationally isolated from the shank. 
     In some embodiments, the bolster may comprise a puller attachment. The bolster may also be in communication with the driving mechanism through a press fit pin. 
     In some embodiments, the assembly may comprise a holder. The holder may be indexible, and the holder may comprise a substantially axially symmetric geometry. The holder may be in communication with the shank through a thread form. The holder may also comprise a spring loaded catch or a racketed cam. 
     In another aspect of the present invention, a method of utilizing a degradation assembly comprises, providing an degradation assembly comprising a bolster intermediate a shank and a tip, the tip comprising a substrate bonded to a diamond material comprising a symmetric, substantially conical shape, the diamond comprising an apex coaxial with the tip, and the diamond being over 0.100 inches thick along the central axis of the tip. Then an operator actuates the driving mechanism for a first period of time. Next, an operator rotates the degradation assembly along its central axis to another indexed azimuth. An operator then actuates the driving mechanism for a second period of time. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-sectional diagram of an embodiment of a pavement milling machine. 
         FIG. 2   a  is a cross-sectional and exploded diagram of an embodiment of a degradation assembly. 
         FIG. 2   b  is a cross-sectional diagram of another embodiment of a degradation assembly. 
         FIG. 3   a  is a cross-sectional diagram of another embodiment of a degradation assembly. 
         FIG. 3   b  is a cross-sectional diagram of another embodiment of a degradation assembly. 
         FIG. 4   a  is a cross-sectional diagram of another embodiment of a degradation assembly. 
         FIG. 4   b  is a cross-sectional diagram of another embodiment of a degradation assembly. 
         FIG. 5   a  is a cross-sectional diagram of another embodiment of a degradation assembly. 
         FIG. 5   b  is a cross-sectional diagram of another embodiment of a degradation assembly. 
         FIG. 6   a  is a cross-sectional diagram of another embodiment of a degradation assembly. 
         FIG. 6   b  is a cross-sectional diagram of another embodiment of a degradation assembly. 
         FIG. 7  is a cross-sectional diagram of another embodiment of a degradation assembly. 
         FIG. 8   a  is a perspective view of an embodiment of a snap ring. 
         FIG. 8   b  is a top view of an embodiment of a snap ring. 
         FIG. 8   c  is a perspective view of another embodiment of a snap ring. 
         FIG. 8   d  is a top view of another embodiment of a snap ring. 
         FIG. 9   a  is a cross-sectional diagram of another embodiment of a degradation assembly. 
         FIG. 9   b  is a cross-sectional diagram of another embodiment of a degradation assembly. 
         FIG. 10   a  is a cross-sectional diagram of another embodiment of a degradation assembly. 
         FIG. 10   b  is a perspective view of a diagram of another embodiment of a degradation assembly. 
         FIG. 11   a  is a cross-sectional diagram of another embodiment of a degradation assembly. 
         FIG. 11   b  is a perspective view of a diagram of another embodiment of a degradation assembly. 
         FIG. 12   a  is a cross-sectional diagram of another embodiment of a degradation assembly. 
         FIG. 12   b  is a cross-sectional diagram of another embodiment of a degradation assembly. 
         FIG. 13  is a flow chart of an embodiment of a method for manually rotating a degradation assembly. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION AND THE PREFERRED EMBODIMENT 
       FIG. 1  is a cross-sectional diagram that shows a plurality of degradation assemblies  101  attached to a driving mechanism  102 , such as a rotatable drum attached to the underside of a pavement milling machine  103 . The milling machine  103  may be an asphalt planer used to degrade man-made formations such as pavement  104  prior to placement of a new layer of pavement. The degradation assemblies  101  may be attached to the drum  102 , bringing the degradation assemblies  101  into engagement with the formation  104 . The degradation assembly  101  may be disposed within a block  105  welded or bolted to the drum attached to the driving mechanism  102 . A holder may be disposed intermediate the degradation assembly  101  and the block  105 . The block  105  may hold the degradation assembly  101  at an angle offset from the direction of rotation, such that the degradation assembly engages the formation  104  at a preferential angle. While an embodiment of a pavement milling machine  103  was used in the above example, it should be understood that degradation assemblies disclosed herein have a variety of uses and implementations that may not be specifically discussed within this disclosure. 
       FIG. 2   a  is a cross sectional exploded diagram of an embodiment of a degradation assembly  101 . In this embodiment the degradation assembly  101  comprises a rotary portion  200  in the form of a shield  201  and a stationary portion  203  in the form of a shank  204 . A conical diamond tip  206  may be bonded to the shield  201 . A compression element  208  in the form of an o-ring  205  may be adapted to be disposed intermediate the shield  201  and the shank  204 . A spring clip  202  may also be adapted to be disposed intermediate the shield  201  and the shank  204 . The o-ring may function as a grease barrier by maintaining grease intermediate the shield  201  and the shank  204 . 
     The embodiment depicted in  FIG. 2   b  discloses a 20%-40% compressed o-ring  205 . The o-ring  205  may be under enough compression that it reduces the cross sectional thickness of the o-ring by 20%-40%. The space between the shield  201  and shank  204  on the o-ring  205  may be small enough to put the o-ring in such a compressed state. It is believed that an o-ring compressed by 20%-40% by the inner surface of the shield and outer surface of the shank may provide enough friction to prevent free rotation of the rotary portion of the assembly  101  during degradation operations. The o-ring  205  may comprise a hardness of 70-90 durometers. The hardness of the o-ring  205  may influence the friction created between the o-ring  205  and the assembly and may also influence the durability and life of the o-ring  205 . The o-ring may also function as a seal to retain a lubricant intermediate the shield and the shank. In this embodiment the assembly  101  may be used in degradation operations until the tip  206  begins to show uneven wear or for a predetermined time period. The assembly may then be manually rotated such that a new azimuth of the tip is oriented to engage the formation first. A wrench flat  207  may be disposed on the rotary portion  200  of the assembly  101  to allow the rotary portion to be turned by a wrench. 
     The rotary portion  200  comprises a tip  206  comprising a cemented metal carbide substrate  260  and a volume of sintered polycrystalline diamond  261  forming a substantially conical geometry with a rounded apex. The diamond  261  is preferably 0.100 to 0.250 inches thick from the apex to the interface between the substrate  260  and diamond  261  through its central axis. The substrate  260  comprises a relatively short thickness, preferably less than the mentioned thickness of the diamond  261 . A short substrate  260  as identified may reduce the potential bending moments experienced by the substrate  260  during operation and therefore reduce the stress on the interface  262  between the substrate  260  and diamond  261  as well as the braze joint  263  bonding the substrate  260  to the rotary portion  200  of the assembly. Preferably, the substrate  260  is brazed to cemented metal bolster  301  affixed to the shield  201 . The shank  204 , bolster  301 , and substrate  260  are preferably share a common central axis. 
     The bolster  301  is preferably wider at its base than the largest diameter of the substrate  260 . However, preferably at their braze joint  263 , the surface of the substrate  260  is slightly larger than the surface of the bolster. This may allow the substrate  260  to overhang slightly. The overhang may be small enough that it is not visible after brazing because braze material may extrude out filling the gap formed by the overhang. While an overhang as small as described may seem insignificant, improvement in field performance is contributed, in part, to it and is believed to further reduce stresses at the braze joint  263 . 
     Preferably, the bolster  301  tapers from the interface with the substrate  260  to a second interface with a steel portion of the shield  201 . At this interface, the braze joint  263  is relieved at the center with a small cavity  265  formed in the bolster  301 . Also the thickness of the braze increases closer to the periphery of the braze joint, which is believed to help absorb impact loads during operation. Also, the steel curves around the corners of the bolster  301  at the second interface  264  to reduce stress risers. 
     The bolster&#39;s  301  shape tapers from the first interface  263  to the second interface  264  with a slightly convex form. The largest cross sectional thickness of the bolster  301  is critical because this thickness must be large enough to protect the steel beneath it as well as spread the formation fragment apart for effective cutting. 
     The described bolster  301  and tip  206  combination have proven very successful in the field. Many of the features described herein are critical for a long lasting degradation assembly  101 . In the prior art, the weakest part of the degradation assembly  101  is generally the impact tip  206 , which fail first. The prior art attempts to improve the life of these weaker tips by rotating the tips  206  through a bearing usually located between the inner surface of a holder bore and the outer surface of a shank  204 . This rotation allows different azimuths of the tip  206  to engage the formation at each impact, effectively distributing wear and impact damage around the entire circumference of the tip  206 . In the present invention, however, the combination of the tip  206  and bolster  301  is currently the most durable portion of the degradation assembly  101 . In fact, it is so durable, that at present the applicants have not been able to create a bearing capable of outlasting this combination. In most cases, the bearing will fail before the tip  206  or bolster  301  receives enough wear or damage sufficient to replace them. At present, the tip  206  and bolster  301  combination is outlasting many of the commercially sold milling teeth by at least a factor of ten. 
     The advantage of the rotary portion  200  with a bolster  301  and tip  206  that is substantially prevented from rotating during operation as described is an extended life of the overall degradation assembly  101 . Rotating the rotary portion manually at predetermined times, or as desired, allows the wear to be distributed around the tip  206  and bolster  301  as well. 
     The assemblies&#39; longer life benefits operators by reducing down time to replace worn assemblies and reducing replace part inventories. 
       FIG. 3   a  is a cross sectional diagram depicting o-ring  205  disposed within a recess formed in the shank  204 . The o-ring may still be under enough compression to substantially prevent the rotary portion&#39;s rotation.  FIG. 3   b  discloses a back up  350  also disposed within the groove. The back up  350  may comprise a metal ring with at least one substantially slanted surface. The back up  350  may be placed intermediate the o-ring  205  and the shank  204 . The back up  350  may aid in compressing the o-ring as well as protect it during assembly. 
       FIG. 4   a  discloses an additional compressive element  306 , which may also be an annular elastic element. The additional compressive element may be disposed substantially within the stationary portion  203  adjacent the first compressive element, which is within the rotary portion. It is believed that the interaction between these two elements  208  may generate sufficient friction to prevent free rotation. 
       FIG. 4   b  discloses a degradation assembly  101  with a rotary portion  200  comprising an integral shank  302 . The stationary portion  203  comprises a holder  303  with a bore adapted to rotational support the integral shank. A compressible element  208  in the form of at least one rubber ball  304  is disposed intermediate the shank  302  and the holder  303 . The compressible element may be a elastic ball, wedge, strip, block, square, blob, or combinations thereof. The assembly may also comprise an o-ring  205  disposed intermediate the shank  302  and the holder  303 . The o-ring may function as a sealing element to retain lubricant within the assembly. It is believed that the at least one rubber ball  304  may substantially prevent the rotation. The assembly  101  may also comprises a puller attachment  305  disposed on the bolster  301 . The puller attachment may be used to remove the rotary portion  200  of the assembly from the holder  303 . 
       FIG. 5   a  discloses a compression spring  401  is disposed within the holder  303  such that a portion of the spring  401  engages the integral shank  302 . It is believed that the compression spring  401  may put enough pressure on the shank  302  to prevent free rotation of the rotary portion  200 . 
       FIG. 5   b  discloses a press fit pin  402  as a compressible element  208 . It is believed that the press fit pin  402  is adjusted to put enough pressure on the shank  302  of the rotary portion  200  to prevent free rotation. 
       FIG. 6   a  discloses a set screw  403  adapted to energize a compressible element  208 . 
       FIG. 6   b  discloses an outer edge of the rotary portion with an integral shank than wraps around a portion of the holder  303 . A compressible element  208  in the form of a compressed o-ring  205  is disposed there between. The assembly may also comprise a snap ring  202  disposed intermediate the shank  302  and the holder  303 . The snap ring  202  may prevent the rotary portion  200  from separating from the stationary portion  203 . 
       FIG. 7  discloses a degradation assembly  101  disposed within a holder  303  and a block  104 . The rotary portion  200  comprises a bolster  301 , a shank  302 , and a holder  303 . The bolster  301  and the shank  302  are affixed to each other. The shank  302  is in mechanical communication with the holder  303  through a threadform  601 . The block  104  comprises a bore  604  with a neck  605  where the bore  604  narrows. The holder  303  may comprise a groove  606  adapted to receive the neck  605  of the bore  604  and a compressible element  208  in the form of at least one slot  602 . It is believed that the at least one slot  602  may allow the holder  303  to temporarily compress to allow the holder  303  to squeeze past the neck  605  within the bore  604  of the block  104  until the neck  605  is seated within the groove  606 . After the neck  605  has been seated in the groove  606  a portion  607  of the holder  303  comprising the slot  602  may occupy a portion of the bore  604  that is smaller than the natural circumference of the portion  607  of the holder  303 . This may cause the portion  607  of the holder  303  to exert an outward force onto the inner wall  603  of the holder  303 . It is believed that the force exerted by the portion  607  of the holder  303  onto the inner wall  603  of the bore  604  may prevent the assembly  101  from freely rotating but allow for manual rotation of the assembly  101 . 
       FIGS. 8   a - 8   d  disclose different embodiment of snap rings  202  that may be used as compressible elements  208  to prevent free rotation of an assembly  101  while still allowing for manual rotation.  FIGS. 8   a  and  8   b  disclose a snap ring  202  with an oval shape. When the snap ring is disposed intermediate the shank and holder the oval shape is forced into a circular shape causing a portion of the snap ring  202  to collapse onto the shank and holder preventing the free rotation. 
       FIGS. 8   c  and  8   d  disclose a snap ring  202  with at least a flat side  701 . The flat side  701  may also prevent free rotation by collapsing on both the shank and holder. 
       FIGS. 9   a  and  9   b  disclose rotationally indexible degradation assemblies  101 . The assembly comprises a holder  303  with a bore  802 . The shank  302  comprises longitudinal surfaces  801  complementary to those formed in the bore.  FIG. 8   a  discloses a the shank  302  with a hexagonal shape. The bore  802  in the holder  303  comprises a corresponding hexagonal shape of substantially the same proportions as the shank  302 . The shank  302  is adapted to be inserted into the bore  802  of the holder  303  in six different orientations due to the hexagonal shape of the shank  302 . Each of the different positions may orient a different azimuth of the tip  206  towards a working surface during operation. As one indexed location begins to wear the tip  206  the assembly  101  may be rotated to distribute the wear of the tip  206  to at another azimuth. 
       FIG. 9   b  discloses a shank  302  and bore  802  of the holder  303  forming a star shape. This shape would allow for multiple azimuthal positions of the conical diamond tip  206 . 
       FIGS. 10   a  and  10   b  disclose a rotationally indexible degradation assembly  101 . A bolster  301  is intermediate a conical diamond tip  206  and a shank  302 . An o-ring  205  may be disposed around the shank  302 . The assembly may be disposed within a holder  303 . The side of the bolster  301  opposite the conical diamond tip  206  may comprise circumferentially equally spaced holes  901 . These holes  901  may be adapted to receive interlocking elements  902 . The holder  303  may comprise corresponding holes  901  adapted to receive interlocking elements  902 . This embodiment may be used in degradation operations until the conical diamond tip  206  begins to show uneven wear at which time the rotary assembly may be detached from the holder  303  by pulling the holder  303  and the bolster  301  away from each other causing the press fit pins  902  to come out of their holes  901 . The bolster may then be rotated until another set of holes  901  align, the interlocking elements  902  are reinserted, and then the bolster  301  may be pressed onto the holder  303 . In some embodiments, the interlocking elements are integral to with the stationary or rotary portions of the assembly. 
       FIGS. 11   a  and  11   b  discloses a racketed cam system  1001  with a set of indexible teeth  1002  disposed around the shank  302 . The holder  303  may comprise a tab  1003  adapted to interface with the indexible teeth  1002  on the shank  302 . The tab  1003  and the teeth  1002  may interact in such a way that the tab only allows for the teeth  1003  to rotate in a single direction. The tab  1003  may also interfere with the single direction of rotation enough as to prevent free rotation of the assembly  101  while in use. 
       FIG. 12   a  discloses a rotary portion that comprises the conical diamond tip  206  and a shield  201 . The stationary portion of the assembly may comprise the shank  302 . The shank  302  may comprises equally circumferentially spaced flat surfaces  1102  adapted to receive a set screw  1101 . As a conical diamond tip  206  begins to wear the set screw  1102  may be loosened, the shield  201  rotated, and the screw  1102  reset. 
       FIG. 12   b  discloses an indexible holder  1201  that comprises axial flats. In this embodiment, the holder comprises a hexagonal shape. When the assembly  101  begins to show uneven wear the holder  1201  may be removed from a block, rotated, and then reinserted. 
       FIG. 13  is a flow chart of a method for rotating a degradation assembly to another index point to lengthen the life of the assembly. The steps include providing an degradation assembly comprising a bolster intermediate a shank and a tip, the tip comprising a substrate bonded to a diamond material comprising a substantially conical shape, the diamond comprising an apex coaxial with the tip, and the diamond being over 0.100 inches thick  1301 . The assembly may then be put into use by actuating the driving mechanism for a first period of time  1302 . Once the assembly shows enough uneven wear, the next step includes stopping the driving mechanism and rotating the degradation assembly to another index point  1303 . The degradation process is restarted by actuating the driving mechanism for a second period of time  1304 . 
     Whereas the present invention has been described in particular relation to the drawings attached hereto, it should be understood that other and further modifications apart from those shown or suggested herein, may be made within the scope and spirit of the present invention.