Abstract:
The present invention relates to the application of surface coatings to treated aluminum articles utilized on aircraft, and more particularly to a system for masking portions of aluminum aircraft wheel and brake components for application of surface coatings to reduce or prevent wear and/or corrosion to the aluminum article. The system may be utilized for new aluminum aircraft components as well as aircraft components that have been subjected to non-destructive testing. The masking components are constructed and arranged to cooperate with portions of the aluminum component in a sequential manner to allow for application of multiple layers of primer and/or topcoat without removal of prior masking components so that a coated component complies with the manufacturer&#39;s written requirements for that component.

Description:
FIELD OF THE INVENTION 
     This invention relates to treated aluminum articles for aircraft, and more particularly to a system for masking portions of aluminum wheel and brake components for application of surface coatings to reduce or prevent wear and/or corrosion to the aluminum article. The system may be utilized for new aluminum aircraft components as well as aircraft components that have been subjected to non-destructive testing. 
     BACKGROUND OF THE INVENTION 
     Aluminum alloys are typically utilized for wheel and brake components on an aircraft. For example, aluminum alloys that are commonly used in wheel structures for aircraft include Aluminum Association Series alloys 2014-T6, 2040-T6 and 7050-T74. These alloys are specific alloys within the Aluminum Association Series of alloy classes 2XXX and 7XXX, respectively. These alloys are attractive due to their high strength and fracture toughness characteristics. Although the 2XXX and 7XXX aluminum alloys exhibit high strength characteristics, they are more prone to corrosion than other aluminum alloys. This corrosion includes general corrosion, pitting, stress corrosion cracking, and intergranular attack. 
     To counteract the problems related to corrosion, aluminum aircraft wheel and brake components are provided with a hard anodized coating. One type of accepted hard-anodized coating involves the application of a sulfuric acid anodic coating in combination with a sodium dichromate sealant to the aluminum surface. Thereafter, depending on the type of wheel assembly and the manufacturer&#39;s recommendations, portions of the wheel or brake may be further coated over the hard anodizing with the application of a primer. Other portions of the wheel may be further coated with a paint type topcoat. 
     One common type of aircraft wheel includes an inner wheel half and an outer wheel half. Bolts, washers and nuts hold the two halves together while an o-ring seals the joint between the two wheel halves. The inner wheel half additionally includes drive lugs or inserts for the interaction with the brake assemblies, and may include heat shields to reduce the transfer of brake heat to the wheel. An inner bore extends through both halves of the wheel and is constructed and arranged to house at least two bearing and seal assemblies, and may further be constructed to include retaining rings, grease retainers or the like. In addition, either half of the wheel may include sensors, thermal relief plugs, over-inflation plugs or the like that require ports or bores that extend through the thickness of the wheel. Another type of aircraft wheel includes an inner wheel half and an outer wheel half. The inner and outer halves are held together by a split ring. 
     Current maintenance practices for aircraft wheels require inspections of aircraft wheels at predetermined intervals and for various reasons. For example, inspections may be required for wheels that have exceeded a predetermined number of landings or have had a predetermined number of tire changes; or the aircraft may have suffered a catastrophic tire failure or an inspection may be required at annual aircraft inspections. While some of these inspections are simply visual inspections that can be accomplished by merely removing the tire from the rim, others require surface coatings to be removed for non-destructive testing (NDT). For example, a fluorescent penetrant inspection (FPI) is required during every major overhaul. In order to perform this inspection, the paint must be removed from the wheel. Following NDT inspection, provided the wheel checks to standards, the primers, lubricants and topcoats are reapplied to the wheel. The task of stripping and reapplying the paint for FPI inspection during maintenance and overhaul is labor intensive and significantly increases the cost of maintaining the aircraft. 
     In general, paint is removed from the wheel using chemical paint remover, or media blast equipment utilizing media like walnut shells, plastic, water or other media suitable for removing lubricant, primer and topcoat without damaging the hard anodized coating of the wheel or brake. The technician then refers to a manual for requirements relating to primer and/or topcoat coatings for the component. Different manufacturers and wheel constructions have different requirement as to which portions of the wheel get the various coatings. In a typical scenario, a technician will apply masking tape, paper, cardboard etc. to portions of a hard-anodized component such as a wheel that is devoid of other surface coatings. Any unwanted tape is thereafter trimmed away with a razor knife until the desired area is masked from receiving primer. The wheel will then be coated with a primer, via an air type spray gun, and dried. This step may be further complicated with the requirement of applying primer to both sides of the wheel which may require an extra drying cycle. After completion of the primer step, additional portions of the wheel will be masked with tape and trimmed with razor blades for application of a topcoat. The tape and any glue that remains attached to the wheel must be removed with solvents without damaging the primer or topcoat. The wheel can thereafter be assembled and shipped to a desired location for installation on an aircraft until the next inspection is required. 
     Therefore, there is a need in the art for a system of masking components that are adapted for temporary attachment to various aluminum components, such as aircraft wheels or brake components. The masking components should allow portions of the component to be masked from receiving unwanted surface coatings during an air gun spraying operation. The masking components should also be designed to be added over other masking components sequentially to allow for multiple coatings which may not be over the same portions of the component without removal of the masking components used for earlier coatings. The components should be easily removed after coating the component for reuse on other like constructed components. The masking components should also be constructed from a material that allows easy removal of prior coatings to allow for extended use of the masking components. 
     SUMMARY OF THE INVENTION 
     The present invention relates to the application of surface coatings to treated aluminum articles utilized on aircraft, and more particularly to a system for masking portions of aluminum aircraft wheel and brake components for application of surface coatings to reduce or prevent wear and/or corrosion to the aluminum article. The system may be utilized for new aluminum aircraft components as well as aircraft components that have been subjected to non-destructive testing. The masking components are constructed and arranged to cooperate with portions of the aluminum component in a sequential manner to allow for application of multiple layers of primer and/or topcoat without removal of prior masking components so that a coated component complies with the manufacturer&#39;s written requirements for that component. There are commercial considerations that are satisfied by the masking system or kit; considerations which are not entirely satisfied by state of the art products. The masking system is formed of relatively few component parts that are inexpensive to manufacture by conventional techniques. The masking system or kit is also capable of being packaged and shipped in a condensed state. In addition, the system is modular and facilitates the creation of a family of masking system and kits which may share common, interchangeable components. 
     Finally, there are ergonomic needs that the present masking system or kit satisfies to achieve acceptance by the end user. The masking system is easily and quickly assembled using minimal hardware and requiring a minimal number of tools. Further, the system does not require excessive strength to assemble or include heavy component parts. Moreover, the system assembles together in such a way so as not to require removal of previously attached masking components, whereby all of the masking components may be removed in a single operation. 
     Accordingly, it is an objective of the instant invention to provide a masking system for aluminum aircraft components. 
     It is a further objective of the instant invention to provide a masking system for aircraft components that is quick and easy to assemble with a minimum amount of tools. 
     It is yet another objective of the instant invention to provide a masking system for aircraft components that assembles in a sequential manner to allow multiple layers and types of coatings to be sequentially applied without removing the masking components from prior coating operations. 
     It is a still further objective of the invention to provide a kit of masking elements for masking aircraft components. 
     Other objects and advantages of this invention will become apparent from the following description taken in conjunction with any accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. Any drawings contained herein constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  is an exploded view of one type of an aircraft wheel; 
         FIG. 2  is a section view taken along lines  3 - 3  and  4 - 4  of  FIG. 1 ; 
         FIG. 3  is a section view taken along lines  3 - 3  of  FIG. 1 ; 
         FIG. 4  is a section view taken along lines  4 - 4  of  FIG. 1 ; 
         FIG. 5  is an exploded view of one type of aircraft wheel; 
         FIG. 6  is a section view taken along lines  6 - 6  of  FIG. 5 ; 
         FIG. 7  is a partial section view taken along lines  6 - 6  of  FIG. 5 ; 
         FIG. 8  is a partial section view taken along lines  6 - 6  of  FIG. 5 ; 
         FIG. 9  is a perspective view of one embodiment of an aircraft wheel; 
         FIG. 10  is a perspective view of the outer half of the aircraft wheel shown in  FIG. 9 , illustrating a masking kit; 
         FIG. 11  is a perspective view of the outer half of the aircraft wheel shown in  FIG. 10 , illustrated with the first bearing cup masking element in place; 
         FIG. 12  is a perspective view of the outer half of the aircraft wheel shown in  FIG. 10 , illustrated with the second bearing cup masking element in place; 
         FIG. 13  is a perspective view of the outer half of the aircraft wheel shown in  FIG. 10 , illustrated with the wheel packing masking element in place; 
         FIG. 14  is a perspective view of the outer half of the aircraft wheel shown in  FIG. 10 , illustrated with the inner bore masking element in place; 
         FIG. 15  is a perspective view of the inner half of the aircraft wheel shown in  FIG. 9 , illustrated with one embodiment of the masking kit of the present invention; 
         FIG. 16  is a perspective view of the inner half of the aircraft wheel shown in  FIG. 15 , illustrated with the first bearing cup masking element in place; 
         FIG. 17  is a perspective view of the inner half of the aircraft wheel shown in  FIG. 15 , illustrated with the second bearing cup masking element in place; 
         FIG. 18  is a perspective view of the inner half of the aircraft wheel shown in  FIG. 15 , illustrated with the first bearing cup masking element and packing groove masking element in place; 
         FIG. 19  is a perspective view of the inner half of the aircraft wheel shown in  FIG. 15 , illustrated with the first bearing cup masking element, packing groove masking element and packing surface masking element in place; 
         FIG. 20  is a perspective view of the inner half of the aircraft wheel shown in  FIG. 15 , illustrated with the second wheel bore masking element and drive lug masking element in place; 
         FIG. 21  is a perspective view of one embodiment of an aircraft wheel, illustrating a wheel having an inner portion and an outer slip ring; 
         FIG. 22  is a perspective view of the aircraft wheel shown in  FIG. 21 , illustrated with one embodiment of the masking kit of the present invention; 
         FIG. 23  is a perspective view of the inner portion of the aircraft wheel illustrated in  FIG. 21  with one embodiment of the masking kit of the present invention; 
         FIG. 24  is a perspective view of the inner portion of the aircraft wheel illustrated in  FIG. 21  with the first bearing cup masking element in position; 
         FIG. 25  is a perspective view of the inner portion of the aircraft wheel illustrated in  FIG. 21  with the second bearing cup masking element in position; 
         FIG. 26  is a perspective view of the inner portion of the aircraft wheel illustrated in  FIG. 21  with the first inner bore masking element and slip ring masking element in position; 
         FIG. 27  is a perspective view of the inner portion of the aircraft wheel illustrated in  FIG. 21  with the second inner bore masking element and slip ring masking element in position; 
         FIG. 28  is a perspective view of the inner portion of the aircraft wheel illustrated in  FIG. 21  with the second inner bore masking element, slip ring masking element and drive lug masking elements in position; 
         FIG. 29  is a perspective view of the slip ring portion of the aircraft wheel of  FIG. 21 , illustrated with one embodiment of the masking kit of the present invention; 
         FIG. 30  is a perspective view of the slip ring portion of the aircraft wheel of  FIG. 21 ; 
         FIG. 31  is a perspective view of the slip ring portion of the aircraft wheel of  FIG. 21 , illustrated with the sealing ring masking element in position; 
         FIG. 32  is a perspective view of the slip ring portion of the aircraft wheel of  FIG. 21 , illustrated with the first bearing surface masking element in position; 
         FIG. 33  is a perspective view of the slip ring portion of the aircraft wheel of  FIG. 21 , illustrated with the first bearing surface masking element and sealing ring masking element in position; 
         FIG. 34  is a perspective view of the slip ring portion of the aircraft wheel of  FIG. 21 , illustrated with the second bearing surface masking element in position. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described a presently preferred, albeit not limiting, embodiment with the understanding that the present disclosure is to be considered an exemplification of the present invention and is not intended to limit the invention to the specific embodiments illustrated. 
     Referring to  FIGS. 1-4 , one embodiment of an aircraft wheel  10  is illustrated. The aircraft wheel  10  includes an inner wheel half  12  and an outer wheel half  14 . Bolts  16 , washers  18  and nuts  20  hold the two wheel halves  12 ,  14  together while an o-ring  22  seals the joint between the two wheel halves. The inner wheel half  12  additionally includes drive lugs  24  or inserts  26  for the interaction with the brake assemblies and may include heat shields  28  to reduce the transfer of brake heat to the wheel  10 . An inner bore  30  extends through both halves of the wheel and is constructed and arranged to house at least two bearing and seal assemblies  32 , and may further be constructed to include retaining rings, grease retainers or the like (not shown). In addition, either half of the wheel may include sensors  34 , thermal relief plugs  36 , over-inflation plugs  38 , valve stem assembly  40 , wheel weights  42  or the like that require ports  44  or bores that extend through the thickness of the wheel. 
     Referring to  FIGS. 3 and 4 , the inner half  12  and outer half  14  of a wheel  10  are illustrated with the manufacturer&#39;s primer and topcoat specifications. As illustrated, the inner wheel half includes surfaces that require no paint designated by the indicator  1 . Surfaces that require primer only indicated by the designator  2 . Surfaces where overspray of primer and topcoat are allowed designated by the indicator  3 . The remaining surfaces require primer and topcoat. As indicated by the illustrations, the paint requirements of an aircraft wheel are very specific. Also illustrated is the difficulty that would be encountered in utilizing tape to achieve the manufacturer&#39;s specifications. 
     Referring to  FIGS. 5-8 , one embodiment of an aircraft wheel  10  is illustrated. The aircraft wheel  10  includes an inner wheel half  12  and an outer wheel half  14 . Bolts  16 , washers  18  and nuts  20  hold the two wheel halves  12 ,  14  together while an o-ring  22  seals the joint between the two wheel halves. The inner wheel half  12  additionally includes drive lugs  24  or inserts  26  for the interaction with the brake assemblies, and may include heat shields  28  to reduce the transfer of brake heat to the wheel  10 . An inner bore  30  extends through both halves of the wheel and is constructed and arranged to house at least two bearing and seal assemblies  32 , and may further be constructed to include retaining rings, grease retainers or the like (not shown). In addition, either half of the wheel may include sensors  34 , thermal relief plugs  36 , over-inflation plugs  38 , valve stem assembly  40 , wheel weights  42  or the like that require ports  44  or bores that extend through the thickness of the wheel. 
     Referring to  FIGS. 7 and 8 , the inner half  12  and outer half  14  of a wheel  10  are illustrated with the manufacturer&#39;s primer and topcoat specifications. As illustrated, the inner wheel half includes surfaces that require no paint designated by the indicator  1 . Surfaces that require primer only indicated by the designator  2 . Surfaces where overspray of primer and topcoat are allowed designated by the indicator  3 . The remaining surfaces require primer and topcoat. As indicated by the illustrations, the paint requirements of an aircraft wheel are very specific. Also illustrated is the difficulty that would be encountered in utilizing tape to achieve the manufacturer&#39;s specifications. 
     Referring to  FIG. 9 , an aircraft wheel prepped for repainting is illustrated. The wheel includes an inner half  12  and an outer half  14 . Each of the inner and outer halves includes a portion of the inner bore. 
     Referring to  FIGS. 10-14 , the outer portion of the aircraft wheel shown in  FIG. 9  is shown, illustrating one embodiment of an outer wheel half masking kit  13  of the present invention. The masking kit for the outer half  14  of an aircraft wheel  10  generally includes a first bearing cup masking element  46 , a second bearing cup masking element  48 , a first inner bore masking element  50 , a second inner bore masking element  52 , a packing surface masking element  66  and a tie rod assembly  68 . The first and second bearing cup masking elements are substantially round flat discs in shape having beveled edges  70  and a centrally located aperture  72 . The first and second bearing cup masking elements are sized to fit snugly into the inner bore so that a side surface of the masking elements sets against the bearing cup (race) while the beveled edge  70  faces away from the bearing cup to allow primer to be applied to the inner bore of the wheel half right up to the edge of the bearing cup. The central aperture  72  is sized for cooperation with the tie rod assembly to hold the bearing cup masking elements in place within the inner bore  30  as illustrated in  FIGS. 11 and 12 . Typically, in use, the wheel half would be spray coated with a primer at this stage of the wheel recoating. 
     Referring to  FIGS. 13 and 14 , installation of the inner bore masking elements  50 ,  52  and wheel packing surface masking element  66  are illustrated. The inner bore masking elements are generally disc shaped having a beveled outer perimeter edge  70  and a central aperture  72 . The inner bore masking elements  50 ,  52  are typically slightly larger in diameter than the bearing cup masking elements  46 ,  48 . The inner bore masking elements are constructed and arranged for placement into the inner bore having the beveled edges facing inward so that the outer edge  74  falls proximate to the topcoat paint requirements of the manufacturer. This location is generally close to the edge of the inner bore. The edge provides a suitable contact line to prevent paint and/or overspray from traveling into the inner bore. The central aperture  72  is sized and located to cooperate with the tie bolt holding the bearing cup masking elements in place. This construction allows the inner bore masking elements to be added to the assembly without requiring removal of the bearing cup masking elements. The wheel packing masking element  66  includes an inner face  76  having contours  80  that substantially match the contour of the wheel packing surface  84  ( FIG. 11 ) and feet  82  secured to outer surface  78 . The contoured inner face  76  allows the wheel packing masking element to be snapped onto the wheel packing surface  84  without the need for fasteners or adhesives. Once attached, the packing surface side of the wheel can be painted with topcoat. The wheel can then be inverted for support by the feet  82 , allowing the remaining portions of the wheel to be painted with topcoat. This eliminates a drying cycle that is typically required with the prior art. Once the topcoat layer has cured, the masking elements can be removed from the wheel half with tools for reuse. The masking elements are preferably constructed from a polymeric material such as plastic. In a most preferred embodiment, the masking elements are constructed from a high density polyethylene material (HDPE). This material has exhibited good temperature stability and overspray can be easily removed from surfaces after use. It should be noted that other materials may be utilized without departing from the scope of the invention. Such materials may include, but should not be limited to metals, woods, phenolics and suitable combinations thereof. 
     Referring to  FIGS. 15-20 , an inner half of an aircraft wheel  12  is illustrated with one embodiment of an inner wheel masking kit  11 . The inner wheel masking kit  11  generally includes a first bearing cup masking element  46 , a second bearing cup masking element  48 , a first inner bore masking element  50 , a second inner bore masking element  52 , a packing surface masking element  66 , a packing groove masking element  86  and a tie rod assembly  68 . The first and second bearing cup masking elements are substantially round flat discs in shape having beveled edges  70  and a centrally located aperture  72 . The first and second bearing cup masking elements are sized to fit snugly into the inner bore so that a side surface of the masking elements sets against the bearing cup (race) while the beveled edge  70  faces away from the bearing cup to allow primer to be applied to the inner bore of the wheel half right up to the edge of the bearing cup. The central aperture  72  is sized for cooperation with the tie rod assembly  68  to hold the bearing cup masking elements in place within the inner bore  30  as illustrated in  FIGS. 16 and 17 . Typically, in use, the wheel half would be spray coated with a primer at this stage of the wheel recoating. 
     Referring to  FIGS. 15 ,  18 ,  19  and  20 , installation of the inner bore masking elements  50 ,  52 , packing groove masking element  56 , wheel packing masking element  66  and drive lug masking elements  54  are illustrated. The inner bore masking elements are generally disc shaped having a beveled outer perimeter edge  70  and a central aperture  72 . The inner bore masking elements  50 ,  52  are typically slightly larger in diameter than the bearing cup masking elements  46 ,  48 . The inner bore masking elements are constructed and arranged for placement into the inner bore having the beveled edges facing inward so that the outer edge  74  falls proximate to the topcoat paint requirements of the manufacturer. This location is generally close to the edge of the inner bore. The edge provides a suitable contact line to prevent paint and/or overspray from traveling into the inner bore. The central aperture  72  is sized and located to cooperate with the tie bolt holding the bearing cup masking elements in place. This construction allows the inner bore masking elements to be added to the assembly without requiring removal of the bearing cup masking elements. The packing groove masking element  56  is sized and shaped to cooperate with the wheel packing groove  86  in an interlocking manner. The wheel packing groove generally is constructed and arranged to contain an o-ring or similar sealing type packing element. The wheel packing masking element includes an inner face  76  having contours  80  that substantially match the contour of the wheel packing surface  84  and feet  82  secured to outer surface  78 . The contoured inner face  76  allows the wheel packing masking element to be snapped onto the wheel packing surface  84  without the need for fasteners or adhesives, see  FIG. 19 . The drive lug masking elements  54  are generally elongated elements having a channel  88  sized for a slight interference fit with the drive lugs of the wheel half. This construction allows the drive lug masking elements to be snapped into place without adhesive or fasteners. Once attached, the packing surface side of the wheel can be painted with topcoat. The wheel can then be inverted for support by the feet  82 , allowing the remaining portions of the wheel to be painted with topcoat. This eliminates a drying cycle that is typically required with the prior art. Once the topcoat layer has cured, the masking elements can be removed from the wheel half with tools for reuse. The masking elements are preferably constructed from a polymeric material such as plastic. In a most preferred embodiment, the masking elements are constructed from a high density polyethylene material (HDPE). This material has exhibited good temperature stability and overspray can be easily removed from surfaces after use. It should be noted that other materials may be utilized without departing from the scope of the invention. Such materials may include, but should not be limited to metals, woods, phenolics and suitable combinations thereof. 
     Referring to  FIGS. 21-28 , an alternative wheel design and masking kit are illustrated. In this construction the wheel  90  and inner bore  30  are constructed as a single piece. A slip ring  92  cooperates with the outer diameter of the wheel to provide an outer tire bead. A split ring  95  fits between the wheel  90  and the slip ring  92  to position the slip ring on the wheel. An o-ring or similar seal (not shown) cooperates with packing groove(s)  86  formed into the outer diameter of the wheel. 
     Referring to  FIGS. 22-28 , the wheel portion  90  and the associated masking kit  96  are illustrated. The masking kit  96  generally includes a first bearing cup masking element  46 , a second bearing cup masking element  48 , a first inner bore masking element  50 , a second inner bore masking element  52 , an outer bearing surface masking element  94 , drive lug masking elements  54  and a tie rod assembly  68 . The first and second bearing cup masking elements are substantially round flat discs in shape having beveled edges  70  and a centrally located aperture  72 . The first and second bearing cup masking elements are sized to fit snugly into the inner bore so that a side surface of the masking elements sets against the bearing cup (race) while the beveled edge  70  faces away from the bearing cup to allow primer to be applied to the inner bore of the wheel half right up to the edge of the bearing cup. The central aperture  72  is sized for cooperation with the tie rod assembly  68  to hold the bearing cup masking elements in place within the inner bore  30  as illustrated in  FIGS. 24 and 25 . Typically, in use, the wheel half would be spray coated with a primer at this stage of the wheel recoating. 
     The inner bore masking elements  50 ,  52  are generally disc shaped having a beveled outer perimeter edge  70  and a central aperture  72 . The inner bore masking elements  50 ,  52  are typically slightly larger in diameter than the bearing cup masking elements  46 ,  48 . The inner bore masking elements are constructed and arranged for placement into the inner bore having the beveled edges facing inward so that the outer edge  74  falls proximate to the topcoat paint requirements of the manufacturer. This location is generally close to the edge of the inner bore. The edge provides a suitable contact line to prevent paint and/or overspray from traveling into the inner bore. The central aperture  72  is sized and located to cooperate with the tie bolt  68  holding the bearing cup masking elements in place. This construction allows the inner bore masking elements to be added to the assembly without requiring removal of the bearing cup masking elements. The outer bearing surface masking element  94  includes an inner cylindrical surface  98  having a diameter that substantially matches the outer diameter of the wheel bearing surface  100 . The outer surface of the outer surface bearing masking element includes feet  82  secured thereto. The sized inner diameter  98  allows the bearing surface masking element  94  to be slipped onto the wheel bearing surface  100  for attachment without the need for fasteners or adhesives, see  FIG. 26 . The drive lug masking elements  54  are generally elongated elements having a channel  88  sized for a slight interference fit with the drive lugs of the wheel portion. This construction allows the drive lug masking elements to be snapped into place without adhesive or fasteners. Once attached the exposed surfaces of the wheel can be painted with topcoat. The wheel can then be inverted for support by the feet  82 , allowing the remaining portions of the wheel to be painted with topcoat. This eliminates a drying cycle that is typically required with the prior art. Once the topcoat layer has cured, the masking elements can be removed from the wheel half with tools for reuse. The masking elements are preferably constructed from a polymeric material such as plastic. In a most preferred embodiment, the masking elements are constructed from a high density polyethylene material (HDPE). This material has exhibited good temperature stability and overspray can be easily removed from surfaces after use. It should be noted that other materials may be utilized without departing from the scope of the invention. Such materials may include, but should not be limited to metals, woods, phenolics and suitable combinations thereof. 
     Referring to  FIGS. 29-34 , the slip ring and associated masking kit  98  are illustrated. The masking kit generally includes a slip ring masking element  60 , a first bearing surface masking element  62 , a second bearing surface masking element  64  and a second tie rod  69 . In operation, the slip ring mask element is sized for insertion into the bearing surface of the slip ring  92 , see  FIG. 31 . At this stage the slip ring may be coated with a primer. The first and second bearing surface masking elements  62 ,  64  are constructed and arranged for placement into the bearing bore  102  having beveled edges  70  facing inward so that the outer edge  104  falls proximate to the topcoat paint requirements of the manufacturer. This location is generally close to the edge of the bearing bore. The edge  104  provides a suitable contact line to prevent paint and/or overspray from traveling into the bearing bore. The central aperture  72  is sized and located to cooperate with the tie bolt  68  to hold the bearing surface masking elements in place. This construction allows the bearing surface masking elements to be added to the assembly without requiring removal of the slip ring masking element. 
     All patents and publications mentioned in this specification are indicative of the levels of those skilled in the art to which the invention pertains. All patents and publications are herein incorporated by reference to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference. 
     It is to be understood that while a certain form of the invention is illustrated, it is not to be limited to the specific form or arrangement herein described and shown. It will be apparent to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is shown and described in the specification and any drawings/figures included herein. 
     One skilled in the art will readily appreciate that the present invention is well adapted to carry out the objectives and obtain the ends and advantages mentioned, as well as those inherent therein. The embodiments, methods, procedures and techniques described herein are presently representative of the preferred embodiments, are intended to be exemplary and are not intended as limitations on the scope. Changes therein and other uses will occur to those skilled in the art which are encompassed within the spirit of the invention and are defined by the scope of the appended claims. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in the art are intended to be within the scope of the following claims.