Patent Publication Number: US-9901794-B2

Title: Golf club head with removable component

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 14/150,035, filed Jan. 8, 2014, which is a continuation-in-part of U.S. patent application Ser. No. 13/545,329, filed Jul. 10, 2012, which is a continuation-in-part of U.S. patent application Ser. No. 13/185,324, filed Jul. 18, 2011 (now U.S. Pat. No. 8,226,499), which is a continuation of U.S. patent application Ser. No. 12/696,468, filed Jan. 29, 2010 (now U.S. Pat. No. 7,980,964), which is a continuation of U.S. patent application Ser. No. 11/110,733, filed Apr. 21, 2005 (now U.S. Pat. No. 7,658,686). 
     U.S. patent application Ser. No. 13/545,329, filed Jul. 10, 2012, is also a continuation-in-part of U.S. patent application Ser. No. 13/539,958, filed Jul. 2, 2012, which is claims the benefit of and priority to U.S. Provisional Application No. 61/513,509, filed Jul. 29, 2011. 
     U.S. patent application Ser. No. 13/545,329, filed Jul. 10, 2012, is also a continuation-in-part of U.S. patent application Ser. No. 13/407,087, filed Feb. 28, 2012, which is a continuation-in-part of U.S. patent application Ser. No. 12/643,154, filed Dec. 21, 2009 (now U.S. Pat. No. 8,147,354). 
     The contents of each of the above listed applications are hereby incorporated by reference herein in their entireties. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a golf club, and more particularly to a wood-type club head with separable components. 
     BACKGROUND 
     Some golfers desire a golf club that they can personalize to their playing style. For example, increasing heel or toe-weighting can help correct for a hook or a slice. However, adjustable golf clubs are fraught with problems. The adjustment mechanisms interfere with golf club aerodynamics and also trap soil or other environmental grime. Also, since the adjustment mechanisms can be fragile, they can break during golf. Additionally, the adjustment mechanisms add undesirable mass to the club head. 
     Some attempts have been made to move the mechanisms to the interior of the golf club. For example, U.S. Pat. No. 8,206,243 to Stites describes a club head with movable weight members contained internally. Unfortunately, the removable crown part for accessing the weight members may not cope with stress well. During a powerful drive, the crown may crack or pop off of the club head, causing great frustration to the golfer. It may be found that the removable crown—having much less structural support than the material of the body surrounding the crown—deforms differently than the body and flexes out of shape relative to the body, leading to rapid failures. Also, some removable body part designs such as shown in U.S. Pat. No. 8,435,135 to Stites do not really open up a hollow club head, but simply add a component on top of a fully enclosed part of a club head, or they only provide very limited access to the interior of the club head (e.g., U.S. Pub. 2010/0160091 to Boyd). 
     SUMMARY 
     The invention provides a golf club head with a fully removable component that can withstand the stress of repeated hits. When assembled, the removable component is held in place by a fastening mechanism that holds the component against the club head body. The fastening mechanism includes structural elements that distribute the holding force across the component and tend to equalize the forces around the periphery where the component meets the body. The fastening mechanism may include a post that reaches across the open space within the hollow club head, pulling the removable component towards an opposed main club head body. Preferably, the post receives an assembly screw. The post is connected to the removable component via a plurality of radiating truss structures to distribute forces across the component. The removable component is mated to the club head body at an opening in the body with a periphery complementary to a periphery of the component. The fastening mechanism tends to equalize stresses around this periphery, thus creating a golf club that can be opened but that is also highly effective for playing golf as well as being durable. 
     Since a golf club of the present invention can be opened, it may include a mechanism on the inside for use by a golfer, such as an electronic device or an adjustment mechanism. The golf club may include a weight adjustment system that allows the club to be custom-fitted to a golfer. A weight adjustment system can include a plurality of mount points at which one or more removable weights can be mounted. For example, each mount point can include a threaded receptacle and each weight can include a threaded post. Additionally or alternatively, the club head can include a non-threaded adjustment system that uses Velcro or an adhesive to provide a highly-adjustable mass distribution system. In some embodiments, the adjustment system uses other means such as channels, prongs, spikes, edges, etc., and attachable material such as silicone caulk or other sticky or gummy material that can be pressed in. The adjustment system can include snap-together or snap-in weights or any other suitable mechanism. Where the club head uses threaded weight members, the club head can be provided along with a tool for tightening the weight down on a mount point or removing it. In this way, a golfer can have the club fitted to his or her personal playing style, and can close the club by fastening the removable component in place so that an exterior of the club is smooth and free of features relating to weight mounting and thus can be aerodynamically optimized. 
     Since the adjustable components are contained within an enclosed club head, they are additionally protected from the elements. The adjustable components themselves will not tarnish through rapid exposure to environmental elements. Additionally, the exterior surface of the club head has minimal creases, deformations, inlets, or pockets that may trap and retain dirt and grime—which could otherwise interfere with the mass distribution of the club head. 
     In certain aspects, the invention provides a golf club head that includes a main club head body member defining a hosel, a ball-striking face, and at least a portion of a crown and a sole of the golf club head. The club head has a removable component interchangeably coupleable to the main club head body member at an attachment perimeter to create a playable club. The removable component may be a crown or a sole, for example, or the removable component may define a two-part club head (e.g., a clam-shell club head) or a multi-part club head. 
     The attachment perimeter may include a plurality of tabs and corresponding recesses. Preferably, the main club head body member includes a boss with a screw extending therethrough, the screw being threadably engaged with a post extending from an inner surface of the removable component. A washer may be included, disposed around the screw and retaining the screw within the boss. The removable component may include a majority of a crown and may optionally also include a portion or a majority of a heel-side skirt of the club head, a portion or a majority of a toe-side skirt of the club head, or both. The main club head body member may define a face cup, a hosel, and at least a portion of a sole of the club head. In some embodiments, the main club head body member comprises a majority of the sole. 
     In certain embodiments, the main body member includes a first piece defining the hosel and surrounding the ball-striking face, and an intermediate piece connected to the first and defining a cutaway with an inner periphery at the attachment perimeter. 
     In some embodiments, the club head body includes at least one mount point on an inside surface for attachment of a removable weight. The club head preferably also includes a weight attached to at least one of the mount points. The club head may include a plurality of mount points, wherein the removable weight can be threadably attached to any one of the plurality of mount points. Each mount point may include a casting and a threaded insert disposed within the casting. 
     Aspects of the invention provide a system for fitting a golf club that includes a hollow golf club head defining a crown, a sole, a hosel, and a ball striking face. The system also includes a plurality of mount points disposed on an inner surface of the golf club head with at least one weight member releasably coupleable to any of the plurality of mount points and a removable component for accessing the weight member and the mount points. The plurality of mount points may include at least one mount point on a toe-side of an inside surface of the sole, at least one mount point on a heel side of an inside surface of the sole, or both. Additionally or alternatively, the plurality of mount points includes at least one mount point on a forward area of an inside surface of the sole, at least one mount point on an aft area of an inside surface of the sole, or both. In some embodiments, each mount point comprises a raised casting with a threaded insert therein. 
     Each weight member may include a rigid body, a viscoelastic dampener on a mounting side of the rigid body, a threaded post extending from the mounting side, and a tool interface obverse to the threaded post. The weight member can have a screw extending through the rigid body and providing the threaded post, and a retaining washer holding the screw in the rigid body. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a club head of the present invention. 
         FIG. 2  shows a sole of a club head. 
         FIG. 3  depicts a club head with a removable component released. 
         FIG. 4  illustrates an adjustable mass system according to embodiments of the invention. 
         FIG. 5  gives a view into club head with its crown panel removed. 
         FIG. 6  shows a detail view of an inner periphery of a cutaway of club head body. 
         FIG. 7  depicts an alternative embodiment of removable component. 
         FIG. 8  presents an alternative structure for a removable component. 
         FIG. 9  illustrates a removable crown according to certain embodiments. 
         FIG. 10  shows a club head with a removable crown. 
         FIG. 11  depicts a removable component with a gasket. 
         FIG. 12  depicts an embodiment in which gasket has an L shaped cross-section. 
         FIG. 13  shows a removable component with an L-shaped edge. 
         FIG. 14  shows a two-layer gasket. 
         FIG. 15  shows a close-up detail view of a two layer gasket. 
         FIG. 16  shows a gasket that uses an O-ring. 
         FIG. 17  shows a detail view of the gasket and O-ring. 
         FIG. 18  illustrates a club head body with a removable component removed. 
         FIG. 19  shows a removable weight and a weight mount point. 
         FIG. 20  illustrates a two-piece construction for removable weight. 
         FIG. 21  shows an embodiment in which a removable weight includes a screw. 
         FIG. 22  depicts a threaded insert and a casting of a mount point. 
         FIG. 23  illustrates a threaded insert with a square cross-section. 
         FIG. 24  shows an embodiment for a removable weight. 
         FIG. 25  shows removable weight installed in club head. 
         FIG. 26  gives an informational guide. 
         FIG. 27  shows an informational display that may guide the location of weights. 
         FIG. 28  shows an exploded view of a golf club head. 
         FIG. 29  shows a cutaway view through club head. 
         FIG. 30  illustrate the use of O-ring to create a seal. 
         FIG. 31  shows a connection between crown and a club head body. 
         FIG. 32  depicts a removable component that sits on an intermediate piece. 
         FIG. 33  depicts an intermediate piece fixed to a club head body. 
         FIG. 34  gives another exploded view of club head. 
         FIG. 35  presents a cutaway view through an assembled club head. 
         FIG. 36  gives a detail view of an aft-area junction between components. 
         FIG. 37  gives a detail view of a forward-area junction between components. 
         FIG. 38  depicts a removable component with a plurality of tabs. 
         FIG. 39  shows a removable component and an intermediate piece. 
         FIG. 40  shows a club head with a subtractive mass adjustment system. 
         FIG. 41  gives a cross-section through a weight pad. 
         FIG. 42  shows an internal surface for a mass adjustment system. 
         FIG. 43  gives a close-up of a weight member. 
         FIG. 44  shows a set including translucent weights. 
         FIG. 45  depicts a false floor that includes holes for weight attachment. 
         FIG. 46  shows weight members for attachment to holes. 
         FIG. 47  shows an underside of a false floor. 
         FIG. 48  shows a club head with a removable component. 
         FIG. 49  depicts an assembly screw that fastens a removable component. 
         FIG. 50  illustrates a screw-down clamp mechanism. 
         FIG. 51  shows the use of a rigging mechanism. 
         FIG. 52  shows a capstan screw. 
         FIG. 53  shows a club head with an openable hatch. 
         FIG. 54  an shows openable hatch lifted around its hinged axis. 
         FIG. 55  shows mount points retaining weight members. 
         FIG. 56  shows a mount point and a weight member. 
         FIG. 57  shows a club head with a removable component. 
         FIG. 58  gives a perspective view of a club head. 
         FIG. 59  shows the back of a club head. 
         FIG. 60  gives a bottom view of a club head. 
         FIG. 61  illustrates turning a screw to unlock a removable component. 
         FIG. 62  shows pulling a lever to slide back a clamp. 
         FIG. 63  shows removing a cover. 
         FIG. 64  shows an interior of a club head. 
         FIG. 65  shows a cam lever on a club head. 
         FIG. 66  illustrates the cam lock mechanism provided by a shaft cam lever. 
         FIG. 67  depicts an alternative embodiment for a club head of the invention. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows a club head  101  of the present invention. Club head  101  may be any hollow type of club head such as any wood-type or hybrid-type club head. Preferably, club head  101  is a driver. Generally, club head  101  will include a club head body  105  defining an overall shape of the head. Club head  101  will generally include a ball-striking face  119  and a hosel  113 . Club head  101  also includes a removable component  109 . Any suitable portion of club head  101  may be removable. For example, removable component  109  may be a panel of the sole, the entire sole, an aft body, a crown panel, or other. As shown in  FIG. 1 , removable panel  109  is a crown portion of club head  101 . Club head  101  includes a mechanism to fasten removable panel  109  in place. 
       FIG. 2  shows a sole  123  of club head  101 . Visible on sole  123  is fastening mechanism  131  having screw  127  fastened therein. Screw  127  (or any other suitable fastener such as a barbed post, a cotter pin, or other binder) is accessible from an exterior of club head  101 . When screw  127  is in place, removable component  109  is held in place and club head  101  can be used in playing golf. A golfer can use a tool, such as a specialty tool with a custom tip, to unfasten screw  127  via a tool interface surface, such as a shaped recessed tool port. A golfer can unscrew screw  127  and release it, thereby releasing removable component  109 . 
       FIG. 3  depicts a club head  101  of certain embodiments with a removable component  109  released from club head body  105 . In the depicted embodiment, removable component  109  includes an exterior crown panel  301  and an interior crown frame  305 . While depicted in  FIG. 3  as separated, exterior crown panel  301  and interior crown frame  305  may preferably be fastened together as a single component, either by adhesive, co-molding, by being monolithically formed, or by other suitable means. 
     Removable component  109  includes a post  311  for receiving screw  127 . Component  109  is also held against body  105  by bumpers  325  to prevent rattling and to contribute to the playability of club head  101 . One insight of the invention relates to the need to distribute stresses about a perimeter of component  109  for club head  101  to be durable and effective for playing. Without being bound by any particular mechanism, it may be theorized that the impact of hitting a golf ball sends shock waves through a club head. Where a removable panel or component is a simple curved but featureless panel, it will deform differentially relative to an overall club head body. By inclusion of a frame  305  or equivalent set of trusses or buttresses providing radial support between attachment post  311  and crown panel  301 , deformation of removable panel  109  is minimized and made congruent with any deformation of club head body  105 . Thus during a hit, the overall club head responds as a holistic body and imparts energy to the ball in the form of a good coefficient of restitution—rather than dissipating energy through mismatched parts in the form of noise, cracking, or vibrations. Thus the depicted embodiments may provide unexpectedly good playing benefits in comparison to other structures. 
     Since club head  101  includes removable component  109 , access is provided to an interior of club head  101 . Since an interior of club head  101  is accessible, club head  101  can be modified or altered to affect the properties or shape of club head  101 . In certain embodiments, club head  101  includes a system of adjustable mass within the interior. In some embodiments, a removable component alters a shape of a club head. For example, a removable component may include a portion of, or all of, the hosel. A first removable component can be replaced with a second removable component to change a club from having a straight-necked hosel to an offset hosel. 
       FIG. 4  illustrates an adjustable mass system according to embodiments of the invention. As shown in  FIG. 4 , club head body  105  has removable component  109  removed revealing the interior. Club head  101  includes a set of weight mount points  401  therein. Each weight mount point  401  will typically include a mechanism  407  to which a removable weight may be affixed. Also shown in  FIG. 4  is a removable weight  413  affixed to a weight mount point  401  in a toe-side area of the inside of the sole of club head  101 . 
     Weight mount points  401  may be distributed in any suitable locations within club head  101 . In general, it may be preferable to include points  401  on an interior of the sole  123  of club head  101  as golfers may find benefit in keeping a club head center of gravity low. Club head  101  may include any number of mount points  401 , such as, for example, 1, 2, 3, 4, 5, 6, 10 s, etc. In the depicted embodiment, club head  101  includes four mount points  401 —one at each of face side, heel side, toe side, and aft side of the interior of sole  123 . In some embodiments, club head  101  is made to have a certain mass such that when a certain number of removable weights  413  (e.g., one or two) are included, the overall mass of club head  101  is a desirable value  FIG. 5  gives a view into club head  101  with its crown panel removed to illustrate the structure and orientation of frame  305 . Frame  305  is shown as having four arms extending from post  311  towards a periphery of the frame and tapering to points towards the periphery. When screw  127  is tightened from a sole surface of club head  101 , screw  127  pulls removable component  109  closed by tensile force. The tapering arms of frame  305  distribute the force across component  109 , making for a playable club. 
       FIG. 6  shows a detail view of a point where an arm of frame  305  meets an inner periphery of the cutaway of club head body  105 . Frame  305  may rest on bumpers  325 , which may be provided by a viscoelastic material such as rubber or urethane. Inclusion of viscoelastic bumpers or a gasket (discussed in greater detail below) provide for desirable vibration dampening. 
       FIG. 7  depicts an alternative embodiment of removable component  709 . Here, crown panel  301  sits on a frame  705  that has four substantially flat, vertical truss members extending from post  711  to a periphery of frame  705  (only two truss members are shown as frame  705  is drawn in cutaway view). Each of the four truss members substantially defines a triangle with a curved, crown-side edge, radiating away from the central post  711 . Central post  711  receives assembly screw  127 . Each of the radiating arms define open triangles to promote light weight. Central post  711  extends beneath the radiating arms. 
     Aspects of the invention relate to a removable component that provide the desirable features and good playing properties described here. For example, a removable component may include (e.g., as well as or instead of a truss) a heightened mass around the screw receptacle in which the thickness is tapered toward the other portion of the crown. In some embodiments, an internal truss structure is in a circular formation around the screw receptacle. The invention includes any structure that provides a solid consistent compression of the crown with the body. 
       FIG. 8  presents an alternative structure for a removable component  801  for use with club head body  105 . Here, each of the radiating arms includes a shape similar to two joined triangles, not open, radiating from thick central post  811 . Removable component  801  as shown in  FIG. 8  may be monolithically formed (i.e., not have a separate frame and crown panel). This may be preferred for cost and simplicity. 
       FIG. 9  illustrates a removable crown  901  according to certain embodiments. Removable crown  901  is generally characterized by a central post for receiving assembly screw  127  and a set of radiating truss members. Additionally, crown  901  has a pattern of cutaway portions with apparently irregular borders. It may be found that including a network of apparently irregular cutaways promotes weight savings and strength. On the radiating trusses, the irregular border cutaways are cut through the truss members to create apertures. On the crown panel itself, the irregular border cutaways are cut into the inside surface but not all the way through, so that the exterior surface remains intact. 
       FIG. 10  shows a club head  101  of the present invention fitted with a removable crown  901 . Assembly screw  127  extends through the sole of the club head and engages with post  911  of removable crown  901 . This fastens crown  901  to main club head body  105 . The radiating trusses distribute impact energy when ball striking face  119  hits a golf ball, so that club head  101  maintains an overall cohesive form and good coefficient of restitution, imparting high energy to the golf ball. A removable weight  413  can be seen mounted within club head  101  in  FIG. 10 . Additionally, it can be seen that removable crown  901  meets club head body  105  at a seam defined by a flange portion of club head body  105  extending under removable crown  901 . This seam can be closed with a gasket, sealed with an adhesive, held together primarily by pressure from screw  127 , or held in any other suitable fashion. 
       FIGS. 11-17  depict embodiments of the mounting edge (i.e., the outer periphery) for a removable component  109  of a club head of the present invention. 
       FIG. 11  depicts a removable component with a gasket  1105  extending around an outer periphery of the component. Gasket  1105  is preferably a viscoelastic material to prevent rattling and to distribute stresses uniformly 
       FIG. 12  depicts an embodiment in which gasket  1106  has an L shaped cross-section and lies interposed between removable component  109  and main club head body  105 . It may be preferable to include this embodiment where removable component  109  and main club head body  105  are formed of unlike metals to mitigate galvanic corrosion between the metals. Additionally, the pliable form of gasket  1105  aids in forming a water-tight seal between removable component  109  and club head body  105 . 
     Another useful benefit of a gasket relates to production economy. A gasket may be included to hide deviations in tolerance between two edges and thus to create a solid visual appearance of a seal. This allows for manufacturing to meet a slightly relaxed fit tolerance, which can provide considerable savings in time and cost during production. 
       FIG. 13  shows a removable component  109  with an L-shaped edge enclosing gasket  1105 . This allows club head  101  to have the benefit of gasket  1105  in terms of excluding moisture and dampening shock and vibration but allows gasket  1105  to be concealed from an exterior of club head  101 . Concealing gasket  1105  may provide useful benefits in manufacturing as tolerances are more lenient and a uniform appearance of gasket  1105  may not be required, since having a non-uniform gasket  1105  will not interfere with an exterior surface of club head  101  and thus not interfere with aerodynamics (e.g., in the embodiment depicted in  FIG. 13 ). 
       FIG. 14  illustrates use of a two layer gasket. 
       FIG. 15  shows a close-up detail view of the two layer gasket of  FIG. 14 . Here, gasket  1105  is interposed between removable component  109  and interface layer  109 . Interface layer  1109  may be of a softer material than gasket  1105  to improve the fit between removable component  109  and club head body  105 . 
       FIG. 16  shows a gasket that uses an O-ring. Here, gasket  1105  is fitted with O-ring  1113  that extends around an outer periphery of removable component  109 . 
       FIG. 17  shows a detail view of the gasket  1105  and O-ring  1113 . O-ring  1113  protrudes from gasket  1105  and is itself compressible, which ensures a good fit between removable component  109  and club head body  105 . Thus the depicted embodiment may provide for excellent weatherproofing. Also, O-ring  1113  may be found to be an easily replaceable component, thus allowing a club head  101  with a removable component  109  to last a long time and since deterioration of an O-ring does not require that club head  101  be taken out of service. 
     Golf club head  101  has a removable component  109 , which provides access to an interior of the club head. This allows devices or mechanisms to be included inside of golf club head  101 . Any suitable device may be included in club head  101  including, for example, an electronic device such as a shot detector, computer, GPS unit, battery pack, etc. Additionally, club head  101  can include moveable or adjustable mechanisms so that mass properties of a club head can be adjusted. In some embodiments, club head  101  includes one or a set of removable weights  413 . 
       FIG. 18  illustrates a club head body  105  with removable component  109  removed revealing the interior. Club head  101  includes a set of weight mount points  401  therein. Weight mount ports may be arranged in any suitable locations in club head  101 . In some embodiments, a weight mount port  401  is included in one or more of the leading area of the inside sole surface, the trailing area of the inside sole surface, a toe side of the inside sole surface, and a heel side of the inside sole surface. In  FIG. 18 , weight mount point  401  on the toe side of the inside sole surface is shown as having a removable weight  413  mounted on it. 
     In some embodiments, a club head of the invention includes a non-threaded adjustment system that uses Velcro or an adhesive to provide a highly-adjustable mass distribution system. With a non-threaded adjustment system, mass can be added in any continuous or non-discrete arrangement and the mass-positioning possibilities are, in fact, endless. 
     In certain embodiments, the adjustment system uses other means such as channels, prongs, spikes, edges, etc., and attachable material such as silicone caulk or other sticky or gummy material that can be pressed in. For example, an inner surface of the club head can include a solid (e.g., metal, carbon fiber, etc.) honeycomb mesh frame and material such as clay, caulk, compound, etc., can be pressed into the holes in a desired pattern. The adjustment system can include snap-together or snap-in weights or any other suitable mechanism. 
       FIG. 19  illustrates a relationship between removable weight  413  and weight mount port  401 . Weight mount point  401  includes a mounting mechanism—here, a threaded socket  407 . Threaded socket  407  may be fixed into, or created within, weight mount point  401  by any suitable mechanism, such as welding, glue, press-fit, or others. In some embodiments, weight ports are cast as part of the surrounding component and threads are then tapped in. In certain embodiments, the area of the club head defines a casting (e.g., with Ti) and threads are then machined in. 
     Removable weight  413  includes a corresponding threaded post (and may also include a gasket, washer, or other mechanisms, to mitigate vibration and aid in good fit). Removable weight  413  can thus be fixed into, or removed from, an interior of golf club head  101  via a threaded interface. Removable weight  413  preferably includes a tool interface on an exterior surface.  FIGS. 20-25  illustrate constructions of removable weights  413  according to embodiments of the invention. 
       FIG. 20  illustrates a two-piece construction for removable weight  413 . Removable weight  413  sits in mount point  401 , which may be, for example, cast in titanium (e.g., where a portion of or all of a sole  123  of club head  101  is titanium). Removable weight  413  may be made of a dense material such as tungsten alloy. Disposed between the weight and the mount point is a polymer gasket  2005 . In some embodiments, polymer gasket  2005  is adhered to the bottom surface of the tungsten alloy removable weight  413 . Inside of the casting for the mount point is a threaded insert  407  (e.g., adhered to the Ti casting) or threads (e.g., tapped in) to receive threaded post of removable weight  413 . Polymer gasket  2005  may preferably include both horizontal walls as well as vertical walls surrounding the Ti casting of mount point  401  to aid in dissipating shear stresses associated with a ball strike. 
       FIG. 21  shows an alternative embodiment in which a removable weight  2113  includes a screw member  2127  extending through the weight body. A washer  2133  may be disposed between the head of the screw and the weight body. Optionally, a retaining ring may be included. Screw member  2127  mates with threaded insert  407 . 
       FIG. 22  depicts a relationship between threaded insert  407  and the casting of mount point  401 . By including a flat edge, a spline, a corner, or an irregularity, threaded insert can be prevented from rotating within mount point  401 . Threaded insert may have any suitable shape such as rectangle, star-shaped, hexagon, etc. 
       FIG. 23  illustrates an embodiment in which threaded insert  407  has a square cross-sectional shape to prevent rotation within mount point  401 . 
       FIG. 24  shows an embodiment for a removable weight  2401 . Cover  2417  defines an overall shape of removable weight  2401 . Cover  2417  houses insert  2415  that provides mass. Insert  2415  can be any material of a desired density and may be, for example, tungsten-loaded rubber. 
     In some embodiments, insert  2415  further houses a ring member  2409  for additional weighting. Ring member  2409  may be varied to give weight  2401  a desired mass. For example, ring member  2409  may be a steel ring selected from a set of varying thickness, or ring member  2409  may be made from any other suitable material. Cover  2417  may sport medallion  2405 . By including a separate medallion  2405 , different information may be added to weight  2401  after its intended mass is set (e.g., by inserting one or a plurality of ring member  2409 ). Thus, a plurality of cover  2417  can be manufactured uniformly and used to create a variety of different weights  2401 . Different weights  2401  can include different masses through the variation of ring member  2409  and the different masses can be communicated to the user by affixing a different medallion  2405  to the cover  2417 . 
     In certain embodiments, different weight members have different masses by having differing densities in their constituent materials. For example, a weight member body or screw may be made with metals or other materials of different densities (e.g., some tungsten screws, some aluminum screws, etc.) 
     Removable weight  2401  includes a screw extending therethrough for coupling to threaded insert  407 . In some embodiments, removable weight  2401  will include a retaining washer  2423  (e.g., rubber) to hold the screw inside of the weight. 
       FIG. 25  shows removable weight  2401  installed in club head  101 . Weight  2401  is mounted to point  401  on an inside surface of the sole  123  of club head  101  via threaded insert  407  fixed therein (e.g., by glue). In the depicted embodiment, it will be noted that the cover  2417  defines an inner cylinder member that sits on the extended cylindrical wall of mount point  401 . It may be found preferable to have weight  2401  bottom out, when being screwed into place, by having cover  2417  push against the protruding portion of mount point  401 , as depicted. Since insert  2415  is preferably a pliable material such as rubber, the lowermost surface of insert  2415  deforms to conform to the curved inner surface of sole  123  thereby stabilizing removable weight  2401  inside of club head  101 . 
     Since club head  101  can be opened and includes removable or repositionable weights, mass properties of the club head can be adjusted. In some embodiments, club head  101  can be opened by a golfer and re-closed (e.g., as many times as he or she would like). In certain embodiments, club head  101  is open initially, and is fitted to a golfer one time by adjusting the positions of the weights, and then closed and can optionally be sealed shut (e.g., by adhesive) once the club head is fitted to the golfer. Additionally, the club head may be provided with information to guide the positioning of weights. Information may be provided in the form of a color scheme, or labels on the weight mount points  401  or with an informational pamphlet, web page, computer program, or smart phone app that is made available to guide a golfer in locating weights. 
       FIG. 26  illustrates a way in which an interior of club head or an informational guide may be labelled to guide a golfer. In  FIG. 26 , the dashed circles and the numerals correspond to the dashed lines and numerals shown in  FIG. 27 . 
       FIG. 27  shows an informational display that may be used to guide a golfer in locating weights inside of club head  101 . As can be seen by considering  FIGS. 26 and 27  together, it will be noted that toe-side mount point  3  can aid in guiding the ball to the right and thus can correct a hook. Point  4  can guide the ball to the left and thus aid in correcting a slice. Point  1  can move a club head center of gravity back and increase MOI, making a club head more forgiving to off-center hits. Point  2  can create more drive, allowing a skilled golfer to obtain great distance with the club head. 
     An inside of a club head can include an informational display or other indicia on a surface or included (e.g., as a card, pamphlet, etc.) and can be printed, painted, electronic, etc. For example, a club head could include an LED or LCD screen that provides information such as a shot-tracking information, weighting suggestions, hit pattern history, etc. A club head could include slogans, inspirational phrases, initials. Information could be provided as a customizable feature, e.g., made-to-order for a golfer. For example, a golfer could opt to have a club head include a decal or a logo from a favorite sports team or an engraving or motto, etc. In some embodiments, a club head of the present invention is sold with one or a set of removable weights and the golfer is given information to guide the selection of location for the weights. For example, a printed card or pamphlet may be included with the packaging of the golf club. Alternatively, the golfer may be directed to a web page or computer program. A golfer may be provided with a single weight that, when taken with the mass of the club head, provides a desired overall weight (e.g., 195 grams, or 205 grams, etc.). In some embodiments, a golfer is provided with two (or more) weights that add up to the amount of mass necessary to provide the desired overall weight. For example, club head  101  may include a 1 gram weight and a 10 gram weight. Golfers can create a “draw bias” by putting the 10-gram weight in the heel (position  4  in  FIG. 16 ) and the 1-gram weight in the toe (position  3 ). They can create a “neutral bias” by swapping the weights, putting the 10-gram weight in the toe and the 1-gram weight in the heel. 
     Preferably, golf club head  101  is offered in a kit that includes the removable weights and one or more tools for adjusting the club head. For example, assembly screw  127  and the screw of a repositionable weight can include the same size tool interface, and a single tool can be provided. 
     The invention further provides additional embodiments of a golf club with a removable component that creates a playable, watertight club head when assembled.  FIGS. 26-31  illustrate an embodiment that uses an O-ring and a gasket.  FIGS. 32-39  show the use of an intermediate body piece. 
       FIG. 28  shows an exploded view of a golf club head  2601  with a removable component  2609 . Component  2609  sits on gasket  2615  which may be glued to the club head body  2605  (e.g., titanium). Assembly screw  127  is seated in club head body  2605  through the use of a shoulder member  2617  (e.g., Ti, Al, PTFE, carbon fiber, etc.) Screw  127  may be held in the place through a rubber washer or similar mechanism. O-ring  2621  extends around a perimeter of removable crown  2609 . 
       FIG. 29  shows a cutaway view through club head  2601 . It can be seen that center post  2611  extending down from removable component  2609  is fitted with a threaded insert  2619 . This may be, for example, an aluminum insert co-molded into crown  2609 . Screw  127  extends from screw shoulder  2617  to threaded insert  2619  to fasten removable component  2609  into place. 
       FIG. 30  illustrate the use of O-ring  2621  to create a seal between removable crown  2609  and club head body  2605  when the crown if fastened into place. Gasket  2615  helps seat crown  2609  in the correct position and prevents vibration or rattle between the parts. O-ring  2621  creates a moisture barrier and also can be replaced so that club head  2601  provides enduring utility. 
       FIG. 31  shows a leading edge of connection between crown  2609  and club head body  2605 . Crown  2609  seats on gasket  2615  and O-ring  2621  provides a seal. 
       FIG. 32  depicts an alternative embodiment in which removable component  3209  sits on an intermediate piece  3251 . Intermediate piece may be affixed to club head body  3205 . For example, intermediate piece  3251  may be composite, club head body  3205  may include titanium, and intermediate piece  3251  may be glued to club head body  3205 . A benefit of using intermediate piece  3251  includes forgiving manufacturing tolerances. Since the fabrication of club head body  3205  is not the same process that creates the mating surface or interface for attachment to a removable component, the manufacturing process need not satisfy both tolerances simultaneously. The inner perimeter of the cutaway portion of club head body  3205  can have greater variation in manufacturing, as it will be fixed to intermediate piece  3251  and finished. For example, gaps can be filled (e.g., with urethane or glue) and the surface may be finished (e.g., sanded and painted). Intermediate piece  3251  may be manufactured so that the inner perimeter of the cutaway through it will precisely match the outer perimeter of removable component  3209 . 
       FIG. 33  depicts a related embodiment in which intermediate piece  3251  is fixed to club head body  3205 . Here, intermediate piece  3251  includes an aft-most portion of club head  3201  and extends somewhat into a sole region of the club head. Preferably, intermediate piece  3251  is made with a ledge that slides into body  3205  and provides a mating surface for adhesive. Piece  3251  may be cemented to body  3205 , which may be, e.g., titanium. Intermediate piece  3251  may be made from any suitable material including metals and polymers. In some embodiments, intermediate piece  3251  includes carbon-fiber reinforced plastic. 
       FIG. 34  gives another exploded view of club head  3201  to illustrate assembly of removable crown  3209  to the club head. Here, intermediate piece  3251  is illustrate spaced away to aid visualization and will normally be glued to club head body  3205  by ledge  3255 . For manufacturing, ledge  3255  slides into body  3205  and provides a contact surface for glue. Post-manufacturing, removable component  3209  can be attached or removed through the use of screw  127 , which engages with a screw post in component  3209 , as discussed above. 
       FIG. 35  presents a cutaway view through an assembled club head  3201 , showing intermediate piece  3251  disposed between club head body  3205  and removable component  3209 . It can be seen that ledge  3255  on intermediate piece  3251  extends inside of body  3205 . 
       FIG. 36  gives a detail view of an aft-area junction between components for certain embodiments of the invention. For the depicted embodiment, intermediate piece  3251  presents a ledge that extends down into body  3205 . Removable component  3209  sits on a lip surrounding the cutaway through intermediate piece  3251 . 
       FIG. 37  gives a detail view of a forward-area junction between components. Ledge  3255  of intermediate piece  3251  slides under body  3205 . Here too, removable component  3209  sits on the lip surrounding the cutaway through intermediate piece  3251 . 
     One insight of the invention includes the recognition that a golf club—particularly a driver type club—undergoes severe shock during routine play as the club is used to hit a ball at very high speeds. Including a cutaway hole in the overall hollow body of the club head can compromise its structural integrity. During the shock of a shot, the club head can deform, with severe deformation potentially being introduced at seed points around the outer periphery of a removable component or the inner periphery of a cutaway if these points are not adequately supported. The embodiments depicted herein address the structural requirements of such a club head, for example, at least by including a central post with radiating arms. 
     The invention includes any structure that provides a solid consistent compression of the crown with the body. In certain embodiments, a central post uses compressive stress to hold the removable component in place and the radiating arms distribute that stress uniformly about the periphery. In some embodiments, the structure includes circular, elliptical, or oblong channels that emanate from a post, or a structure with a tapering thickness, or a structure with a honeycomb or rectangular lattice structure to provide crown rigidity. Embodiments of the invention provide additional stabilization for the interface between the outer periphery of the removable component and the inner periphery of the cutaway in the form of a gasket or O-ring (see above), or in the form of an interlocking mechanism. 
       FIG. 38  depicts an embodiment in which a removable component  3209  includes a plurality of tabs  3261  provided to interlock with corresponding recess on the club head (e.g., directly on club head body  105  or on intermediate piece  3251 . To best stabilize assembled club head  101 , it may be preferable to include a plurality of post  3261  (e.g., at least 6) distributed around the perimeter of the removable component. 
       FIG. 39  shows a relationship between a removable component  3209  and intermediate piece  3251 . The inner periphery of the cutaway through intermediate piece  3251  includes a plurality of recess  3265 , each corresponding to one of post  3261  on removable component  3209 . The posts and recesses stabilize the component on the club and prevent an edge of the component from shearing away from an edge of the cutaway during play, thus preventing the club head&#39;s overall form from being compromised. 
     In general, embodiments of the invention provide a metal wood golf club head with an access door or removable component on the upper or lower surface. A club head of the invention may include a mass adjustment system, e.g., on the interior of the club. In some embodiments, an upper surface or lower surface attachable shell gives access to the internal surface of a metal wood club head. The shell is fastened (screws, rivets, etc.) and sealed with an adhesive system (tape or “bead”) that prevents moisture from entering the head and provides good sound qualities. The adhesive system may not need strong adhesion to the door to be functional—e.g., it does not have to be excessively “sticky” to work. This may allow multiple installations and removals of the shell(s). 
     A mass adjustment system can be additive or subtractive. Additive mass systems have been illustrated and discussed above. An additive system is based on a minimum head structure that provides acceptable durability, sound, and ball launch conditions. The additive system than also uses mass that may be added. Additive mass may be provided by heavy tape, glued-in weights, screwed-in weights, “snap-in” weights, or any combination of them all to establish the optimum head weight, CG position and moment of inertia. In some embodiments, the head is originally formed through casting, stamping or composite build-up with no discretionary weight onboard—i.e. it is a light weight head. The head has basic functionality with good sound, acceptable durability, and acceptable golf ball launch conditions. Weight pad areas may be designated inside the head, for example, with markings for the placement of discretionary mass. Weights are located in specific combinations on the pad areas to obtain the desired head weight, center of gravity location, and moment of inertia. Weights can be heavy tape (commonly known as “lead tape”), snap-on, heavy metal infused thermoplastic, heavy metal infused rubber, heavy metal infused glue (i.e. “rat glue”), glued-on mass, screws, or others. 
     A subtractive system generally involves a club head that is manufactured to have a mass greater than a desired mass, such that the club can be customized by selectively removing mass. For example, a subtractive system may include specifically located weight pads that are molded (e.g., cast) into the head that can be machined away to establish the optimum head weight, CG position, or moment of inertia. 
       FIG. 40  shows a club head  4001  with a subtractive system. Club head  4001  includes a plurality of mass pads  4009 . Pad can be taken to mean a defined or raised area (e.g., in the sense that a concrete “pad” is poured when building a shed). Weight pads  4009  are preferably areas of the overall body shell of club head  4001  that are thicker than the surrounding areas. Weight pads  4009  are incorporated into the head (cast, stamped, welded) and the baseline head has excessive discretionary mass—i.e. it is heavy. The head has basic functionality, good sound, acceptable durability and acceptable golf ball launch conditions. 
       FIG. 41  gives a cross-section through a weight pad  4009  as manufactured initially in a club head  4001  with a subtractive system. The weight pads may be machined away in a specific pattern to obtain desired head weight, center of gravity location and moment of inertia. For example, a consultant at a pro-shop can use a rotary tool, such as the rotary tool sold under the trademark DREMEL with a grinding attachment, and can remove weight pads  4009  to bias the club head according to a golfer&#39;s swing style. 
     Other mass adjustment systems are provided by the invention for use in a golf club head. 
       FIG. 42  shows an internal surface for a mass adjustment system for a hollow golf club (e.g. driver). Attachment pegs  4209  are fixed to the interior surface of the sole (or other interior or exterior surface) of the golf club head. Pegs  4209  can be provided by a metal, polymer, or other suitable material. Pegs  4209  may be formed as part of the sole material or attached after the sole shape is formed. The depicted mass adjustment system may include one or a plurality of weight members  4213  for attaching to pegs  4209 . 
       FIG. 43  gives a close-up of a weight member  4213 . Weight member  4213  can include a pattern of holes on a bottom surface to correspond to a pattern of pegs  4209 . In an alternative embodiment, weight member  4213  includes a material that is deformable enough that the weight member is initially whole and solid, but is pushed down over pegs  4209 , causing the surface to break and receive pegs  4209  (e.g., a material like a rubbery gelatin) and may be made from silicone, rubber, a polymer, or a similar material. Weights  4213  can be made from a flexible polymer that forms to the shape of the sole surface and snaps onto the attachment pegs. Weights  4213  withstand the impact force when hitting the golf club, but can be removed by prying them off of the pegs. Weights  4213  may be various shapes, sizes, thicknesses and densities. Weights  4213  can be placed anywhere on the peg pattern to achieve desired performance attributes. 
       FIG. 44  shows a set including translucent weights  4413 . Translucent weights  4413  may be preferable to aid a user in understanding a mechanism by which the club head works. A golfer may view weights  4413  (e.g., as shown within  FIG. 44 ) and see pegs  4209  that are inside of weight  4413  and intuitively understand that the weights  4413  are part of a repositionable weight set and understand that they can remove and reposition the weights. 
       FIG. 45  depicts a reversed embodiment in which a club head includes a false floor  4501  that includes holes for weight attachment. False floor  4501  is attached on the interior side of the sole of the golf club head. 
       FIG. 46  shows weight members  4513  for attachment to the holes in false floor  4501 . 
       FIG. 47  shows an underside of the false floor  4501 . Flexible weights  4513  include pegs molded on the bottom that can snap into holes. Weights can be removed by prying them off. The pegs go through false floor to snap in place. 
     The invention provides mechanisms suitable for fastening a removable component to a club head. 
       FIG. 48  shows a club head  4801  with removable component  4809  that can be removed from main club head body  4805 . Central post  4811  extends from removable component  4809  and has a grooved side of the post. Assembly screw  4827  is threaded and the threads engage the groove portion of post  4811 . When screw  4827  is rotated from the outside, the threads pull down on central post  4811 , fastening removable component  4809  to club head  4801 . 
       FIG. 49  depicts an alternative embodiment in which assembly screw  4927  fastens removable component  4909  to main club head body  4905 . Component  4909  may include molded PEEK part  4915 , attached with adhesive and molded with metal thread insert. When screw  4927  tightens, interface surfaces  4937  make contact and translate force downward. Preferably, screw  4923  is captured loosely within boss  4959  on main club head body  4905 . 
       FIG. 50  illustrates a screw-down clamp mechanism that includes a clamp  5031 . Assembly screw  5027  pushes one edge of clamp  5031 , which thus engages and pulls down on mounting buttress  5011  of removable component  5009 . 
       FIG. 51  shows the use of a rigging mechanism in which rigging line  5111  extends through a system of cleats  5123  inside of club head  5101 . 
       FIG. 52  shows capstan screw  5127  in club head  5101 . Rigging line  5111  spools around capstan screw  5127  such that when the screw is rotated, it takes up rigging line  5111 . This applies tension to removable component  5109  through cleats  5123  mounted to removable component  5109 . The illustrates rigging mechanism based on rig-line  5111 , since it is tensioned by capstan screw  5127 , stabilizes club head  5101 , providing a club head that is enjoyable to play. 
       FIG. 53  shows a club head  5301  with an openable hatch  5309  connected to main club head body  5305 . 
       FIG. 54  shows openable hatch  5309  lifted around its hinged axis to reveal an interior of club head  5301 . The depicted structure may be a preferred embodiment, since  5309  is not immediately separable from club head  5301  and thus will remain with the club head. 
       FIG. 55  shows mount points  5501  retaining weight members  5513 . 
       FIG. 56  shows a mount point  5501  and a weight member  5513  as shown inside of a club head in  FIG. 55 . It can be seen that weight members  5513  may include a button that can be pressed to release them from mount points  5501  and that weight members may be inserted by sliding them into mount points  5501 . It may be found preferable to use non-round weight members so that they do not rotate during use of the club head. The cage shape of mount points  5501  may be preferred for fastening the weight members therein. 
       FIG. 57  shows a club head  5701  with removable component  5709  fastened by assembly screw  5727  according to certain embodiments. 
       FIG. 58  gives a perspective view of club head  5701 . 
       FIG. 59  shows the back of club head  5701  to reveal lever  5739  being held in place by assembly screw  5727 . 
       FIG. 60  gives a bottom view of club head  5701 . Shaft cam lever  6051  is visible. Lever  5739  is a central component of the assembly mechanism of club head  5701  and  FIGS. 61-63  illustrate the operation of the assembly mechanism. 
       FIG. 61  illustrates turning screw  5727  to unlock removable component  5709 . 
       FIG. 62  shows a second step—pulling lever  5739  to slid back clamp  5731 . 
       FIG. 63  shows the final step. A user may continue to pull on lever  5739 . Clamp  5731  drops, allowing cover  5709  to be removed. 
       FIG. 64  shows the interior of club head  5701  in some embodiments and depicts an alternative mass adjustment system of certain embodiment. The depicted system includes one or a plurality of assembly posts  6039  to which a mass member  6013  may be fastened. Mass member  6013  may be deformable with an internal shoulder that snaps over the flared head of post  6039 . A person can squeeze mass member  6013 , causing the internal shoulder to deform away from the flared head of post  6039 , allowing mass member  6013  to then be simply lifted off of post  6039 . Additionally or alternatively, mass member  6013  can be provided for one-time mounting on posts  6039 . Mass members  6013  may be non-deformable and may include an internal shoulder that snaps onto post  6039 . Mass members  6013  may be mounted to posts  6039  by an adhesive (e.g., epoxy). In certain embodiments, posts  6039  and mass members  6013  are both threaded and mass members  6013  are screwed onto posts  6039 . 
       FIG. 65  shows cam lever  6301  on club head  5701  for fastening a shaft to the club head. 
       FIG. 66  illustrates the cam lock mechanism provided by shaft cam lever  6051 . The depicted mechanism may be included to allow a golfer to easily adjust their shaft-club head attachment. 
       FIG. 67  depicts an alternative embodiment for a club head  6701  of the invention. Here, the weight mount points need not include a threaded insert. As discussed above, the threads may be tapped in or machined in. Alternatively, the weight members can be non-threadably mounted, e.g., by snap-fit or by adhesives. 
     As used herein, the word “or” means “and or or”, sometimes seen or referred to as “and/or”, unless indicated otherwise. Any documents referenced in the disclosure are hereby incorporated herein by reference in their entirety for all purposes. 
     Although these inventions have been disclosed in the context of certain preferred embodiments and examples, it will be understood by those skilled in the art that the present inventions extend beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the inventions and obvious modifications and equivalents thereof. In addition, while several variations of the inventions have been shown and described in detail, other modifications, which are within the scope of these inventions, will be readily apparent to those of skill in the art based upon this disclosure. It is also contemplated that various combinations or sub-combinations of the specific features and aspects of the embodiments can be made and still fall within the scope of the inventions. It should be understood that various features and aspects of the disclosed embodiments can be combined with or substituted for one another in order to form varying modes of the disclosed inventions. Thus, it is intended that the scope of at least some of the present inventions herein disclosed should not be limited by the particular disclosed embodiments described above. 
     References and citations to other documents, such as patents, patent applications, patent publications, journals, books, papers, web contents, have been made throughout this disclosure. All such documents are hereby incorporated herein by reference in their entirety for all purposes. 
     EXAMPLES 
     Example 1 
     Club heads were made that had a removable crown and did not include a structure of the invention. It was found that the main club head body broke on impact. Without being bound by any particular mechanisms, it may be theorized that the structures of the invention cause the body to compress and tension the crown in harmony with the body when the body deforms, thus providing support and avoiding breakage.