Golf driver with axis of rotation aligned performance optimization

Abstract

A golf club head and method of manufacture in which the club head is part of an assembly that turns about a single axis of rotation. This single axis of rotation for the golf club assembly utilizes a different structure to mitigate the effects of off-center impact. The design provides that any weight / mass distribution to preserve moment of inertia and energy transfer for ball speed at impact should be in or as near possible to a plane oriented perpendicular to this axis of rotation. The face curvature shaping and its radii are perpendicular to the axis of rotation to manage gear effect. Mass is added to the club head also on a line perpendicular to the axis of rotation in the heel and toe of the club.

Description

[0001] TITLE OF THE INVENTION Golf Driver with Axis of Rotation Aligned Performance Optimization

[0002] REFERENCE TO RELATED APPLICATION

[0003] This application is based on and claims priority of provisional patent application 63 / 551 ,564 filed February 9, 2024.

[0004] FIELD AND BACKGROUND OF THE INVENTION

[0005] Applicants’ invention teaches novel golf club design theory, structure, and means for improvement in golf drivers that provides maximum forgiveness for distance and accuracy during off-center impact The unavoidable human error of off-center impact is introduced by every player during every round of golf. No player is so skilled that he can hit golf shots without human error. More “forgiving” golf club designs mitigate the deleterious effects of human error due to off-center impact and will leave the player closer to his intended target, the hole, thereby improving his likelihood of lower scores. The play of golf has always been a simple distance and direction problem.

[0006] There are many diverse designs in golf drivers. However, applicants know of no prior designs that specifically address the problems and solutions set forth in this application. It is also readily observed by applicant that there are different categories of golf clubs in a “set” - each category being designed for specific purposes and playing situations. The golf driver uniquely hits the ball from an elevated tee above the playing surface. And the impact speeds with the driver are the highest speeds and produce the greatest distances in golf. The mass of the golf driver is the least in the set of clubs, while the length of the shaft is greatest. Design criteria for drivers are indeed unique. This suggests different design criteria from all of the other golf clubs, as all other golf clubs are used to hit the ball from the ground / playing surface instead. Broad generalities in golf club design are then not appropriate, as these different purposes dictate different design criteria for each category suggesting unique design answers for the different golf club categories.

[0007] Most golf club designs are first design-optimized for distance and direction performance based upon the assumption of direct central impact, i.e. an impact point in line with the center of gravity of the golf club head and direction of club head travel, thereby providing maximum energy transfer and the intended directional results. Maximum energy transfer during direct central impact is the first and most important design problem for most golf club design efforts, but perfect direct central impact rarely occurs.

[0008] FREE BODY ANALYSIS

[0009] It has long been observed (and every golfer knows from experience) that despite the considerable speed and momentum of the club head, off-center impact will rotate the club head out of its intended correct alignment, energy transfer from the golf club head to the golf ball will be lost / absorbed (during and due to this club head rotation), and the resultant golf ball rebound (shot) will be in an incorrect / unintended direction - with reduced energy transfer / distance, and unintended ball flight curvature will be added. Skilled and unskilled golfers alike can feel this club head rotation from off-center impact, and the unsatisfactory results are visible to every golfer.

[0010] Conventional wisdom in golf club design and empirical observation suggest that impact on the toe side of the face center will rotate the golf club head clockwise (as viewed from overhead by the player ! golfer), distance will be reduced, and “draw” sidespin will be introduced. The converse appears to be true for heel side impact. Still other conventional wisdom suggests impact above the face center will turn the club face upward, thereby increasing loft and producing higher trajectory ball rebound and again the converse seems true.

[0011] Our college physics professors would suggest to us that the appropriate method for examining the effects of off-center impact upon a golf club head design is that of analyzing a “free body moving through space.” Conventional wisdom for golf drivers has assumed we analyze the effects of off-center impact as a “free-body” moving through space and turning about its center-of-gravity due to off-center impact / collision with the golf ball. The external forces acting upon it during off-center impact would then rotate the club head about its center of gravity consistent with that point of force application. Conventional design theory based upon this “free body” analysis would also suggest that “gear effect” spin created during off-center impact could therefore generate gear effect spin in any direction. These have been the basic assumptions driving most golf club design theory development over the centuries.

[0012] OFF-CENTER IMPACT ERROR

[0013] Off-center impact is the most common human error in the play of golf, resulting generally in a loss of distance, misdirected ball rebound, and the introduction of ball sidespin called “gear effect”. Golf club designers have relentlessly sought ways to develop new means to improve energy preservation, face alignment, and direction (alignment / spin) during off-center impact.

[0014] Over the centuries golf has been played, golf club designers have settled into two basic strategies for dealing with the effects of off-center impact:

[0015] 1- higher moment of inertia (“MOI”) club head designs, and

[0016] 2- the addition of curvature to the face / impact surface namely addition of convex face curvatures to the impact surface of lower lofted clubs.

[0017] Conventional wisdom in contemporary golf club design suggests that higher MOI designs increase club stability and mitigate the energy-robbing club head rotation that occurs during off-center impact, thereby better preserving energy transfer (for distance) from the club head to the ball. Lower MOI club head designs suffer significant loss of distance with off-center impact.

[0018] Mis-direction of golf ball rebound and “gear-effect” sidespin are also both introduced by this club head rotation during off-center impact. Contemporary design suggests both can be managed with the addition of a convex face curvature - conventionally called bulge and roll. Bulge is face curvature from heel to toe, and roll is face curvature from top to bottom of the club face. A convex face curvature re-directs the rebound of the golf ball during off-center impact. This combination of mitigation strategies (increased MOI and the addition of convex face curvature) has contributed significantly to the accuracy and distance of contemporary golf club heads during off-center impact, and it represents the current state of the art in golf driver design.

[0019] INCREASED MOMEMT OF INERTIA (“MOI”) STRATEGIES

[0020] Golf club designers have long employed increased MOI design strategies to mitigate the effects of off-center impact. Higher MOI design is intended to stabilize club head misalignment and reduce energy transfer problems resultant from off-center impact.

[0021] Energy is consumed by the club head rotation from off-center impact during the collision with the golf ball. Contemporary golf club design uses several means for increasing MOI in golf club heads. Most commonly in contemporary design, we find hollow structures with perimeter weighting achieved through varied wall thicknesses of that structure, structures for additional weight attachments, and more recently multimaterial solutions that employ reduced density materials where the structural demands permit. And finally center of gravity positioning fore and aft in the club head structure is known to affect “polar” MOI / stability in club heads.

[0022] CONVEX FACE CURVATURE STRATEGIES (BULGE AND ROLL)

[0023] Face curvature strategies have also been developed over the years to answer the need for managing ball flight, spin, and directional corrections resultant from off- center impact. Optimized curvatures are determined experimentally and confirmed with feedback from highly skilled players and more precisely with carefully managed robot testing and analysis.

[0024] This convex face curvature is called “bulge” in the horizontal plane (from heel to toe) and “roll” in the vertical plane (from the bottom of the club head to its top). These bulge and roll curvatures are quantified as “inches of radius” - i.e. a 10-inch bulge radius and 14-inch roll might have been common in old-fashioned wooden driver clubs. Modern perimeter-weighted drivers with their higher MOI have slightly “flattened” the faces of golf drivers to become nearer to 14-inch bulge and 14+ inches of roll.

[0025] GEAR EFFECT SIDE SPIN

[0026] Off-center impact rotates the club head about its center of gravity, and launches the ball with reduced energy transfer. But this launch rebound is also in an unintended direction from the club face becoming mis-aligned as it rotates. Furthermore unintended flight curvature is introduced into the ball from “gear effect” side spin. Even the vertical launch angle is observed to be slightly changed with off-center impact.

[0027] Conventional wisdom based upon decades of experience and trial and error has taught golf club designers that adding convex curvature to the face of the lower lofted golf club heads can offset this misdirection in ball flight caused by the sidespin resultant from gear effect during off-center impact quite effectively.

[0028] In order to manage the sidespin created we must first understand how it is created. When the golf ball is compressed during impact, it is effectively “stuck” on the golf club face for an instant, and friction between the ball and the rotating club head adds side-spin ball rotation characteristics in the opposite direction of the club head rotation as the club head is turned during off-center impact. The ball spin phenomenon of “gear effect” is therefore introduced - adding spin to the golf ball rebound with its resultant influence upon ball spin and flight curvature. The gear effect spin is essentially in addition to the back spin already present from loft.

[0029] Further experience has taught us that when this convex curvature (conventionally bulge and roll) is added to the face impact surface properly, it can alter the ball flight rebound direction from that of an otherwise mis-directed off-center rebound. This ball flight curvature and gear effect spin phenomenon can therefore be managed effectively to result in ball flight curvature that actually returns to the originally intended target line - despite this off-center impact back.

[0030] Conventional wisdom and experimentation have taught designers the correct amount of face curvature is most basically a matter of how far behind the face / impact point the club head center of gravity is located and what the clubhead MOI is. Both affect how rapidly the club head can be rotated by off-center impact thereby determining in large part the amount of gear effect spin imparted into the golf ball.

[0031] The correct amount of face curvature is whatever curvature is sufficient to neutralize the rebound mis-direction (from the club face misaligned during off-center impact) and then create the needed amount of gear effect ball spin directional correction during ball flight. This is done by matching the sidespin curvature with the mis-aligned rebound direction, so as to curve the ball flight from the incorrect direction caused by off-center impact back to the intended target line with this gear-effect influenced flight curvature. This is possible and can be determined experimentally. Better conceived golf clubs do this by design in the current state of the art.

[0032] Too much face curvature (a shape too convex) initiates rebound too far away from the intended target line and will not allow this curved ball flight to return to the intended target line. It stops short of returning to the target line. And conversely, too little curvature will result in ball rebound flight that begins on one side of the intended target line and actually curves across that target line to the opposite side. These correct determinations for face curvature are found empirically, as no formulae currently exist for calculating optimum bulge and roll.

[0033] “BULGE AND ROLL” AS A FUNCTION OF CENTER OF GRAVITY (CG) LOCATION

[0034] Conventional wisdom, experimentation, and study of club head MOI have also taught us the more rearward the center of gravity is located (or the more the MOI is increased), the flatter the face must be (i.e. less bulge and roll) to achieve optimum accuracy results from off-center impact. The converse is also true.

[0035] Thus, club heads with more forward centers of gravity or with reduced MOI require more bulging face curvature (increased convexity) to preserve their target line return accuracy. Design cosmetics and player preferences can be at odds with “gear effect” accuracy performance for this design attribute. Regardless, it is well-established that accuracy during off-center impact can absolutely be improved with correct bulge and roll curvature on the face of low-lofted golf club heads. And, it is worth noting that these directional optimizations can also be at odds with energy transfer optimizations. SUMMARY OF THE INVENTION

[0036] Applicant’s invention advances novel golf club design theory, providing new structure and means for golf driver design that make possible next thresholds of distance and accuracy performance responsive to the unavoidable human error of off- center impact. Applicant’s invention finds that the “free body’’ analytical methodology used for contemporary golf club design has been in error. Applicant’s invention asserts instead that the golf club head is part of an “assembly” that turns about a single axis of rotation and that it is not in fact a “free body” as contemplated by conventional golf club design wisdom (See Figure 1 ). This discovery of a single axis of rotation for the golf club assembly (hereinafter called “ART” or “ART Design”) suggests fundamentally different structure and means for development of MOI and face curvature strategies to mitigate the effects of off-center impact.

[0037] Applicant’s invention provides that any weight / mass distribution / structural strategies to preserve MOI (to counter club head rotation) and / or energy transfer for ball speed at impact should be oriented perpendicular to this same ART alignment club head rotation. Applicant’s invention further concludes that face curvature shaping and its radii must be properly dimensioned and constructed perpendicular to the “club head’s ART in order to offset gear effect ball spin properly. Applicant’s invention also requires only one face surface curvature aligned perpendicular to the ART to manage gear effect. MOI effectiveness is maximized by adding mass on a line perpendicular to the ART in the heel and toe of the club.

[0038] OBJECTS OF THE INVENTION

[0039] It is an object of the invention to increase accuracy and distance that better forgives and mitigates the effects of off-center impact as compared to prior art drivers. The advantage to the golfer using drivers that employ applicant’s invention is to hit longer and more accurate drives resulting in lower golf scores. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a perspective of the golf club driver of the conventional design in which the shaft is deformed during the swing and the upper portion of the shaft centerline is aligned with the golf club head center of gravity illustrating the various forces on the club head at impact.

[0041] Figure 2 is a perspective view of the inventive driver in which the shaft is deformed during the swing illustrating the axis of rotation in which the upper portion of the shaft centerline is aligned with the drooped golf club head center of gravity.

[0042] Figure 3 is a front view of a conventional golf club head illustrating the conventional club face curvature orientation which is horizontal for bulge and vertical for roll.

[0043] Figure 4 is a front view of applicant’s golf club head illustrating the axis of rotation face curvature orientation which is the face curvature perpendicular to the axis of rotation and placement of mass perpendicular to the axis of rotation.

[0044] Figure 5 is a front perspective view of applicant’s golf club head illustrating the placement of weights in the golf club head perpendicular to the axis of rotation.

[0045] DETAILED DESCRIPTION OF THE INVENTION

[0046] Applicant has determined that the golf club head is not a free body at impact. Applicant again asserts this analytical construct is in error. As seen in Figure 1 , golf club heads 10 are instead part of a golf club “assembly” 12 that includes the golf club head 10 that is rigidly attached to a shaft 14 with a shaft centerline 15 and a grip (not illustrated) at the top of the shaft 14. This complete assembly 12 of the club head 10, shaft 14 , and grip absolutely dictates what orientations the club head 10 rotation can take during off-center impact. A SINGLE AXIS OF ROTATION FOR GOLF DRIVER HEADS

[0047] As noted above, the golf clubhead 10 is not a “free-body” moving in space as our physics professors suggested. It is instead almost rigidly fixed to its shaft 14, which ultimately dictates its single Axis Of Rotation (ART) 16 as seen in Figures 1 and 2. This is also true in the other categories of golf clubs, namely hybrids, irons, wedges, and putters.

[0048] Because the shaft centerline 15 and the club head center of gravity are not aligned with one another (by USGA rule for all golf clubs except putters), centrifugal forces generated during the golf swing act on this entire golf club assembly 12 to deform the shaft 14. As seen in Figure 1 this deformation brings the upward portion of the shaft centerline 15 generally into closer alignment with a club head center of gravity 20 as it moves into impact, thereby introducing the dynamic effects of shaft “droop” 22, dynamic loft 24, and face closure 26. As can also be seen in Figure 1 , the deformed shaft has a lower portion of the shaft 14 with a centerline 17 passing through the bore 19 in the golf club head 10.

[0049] Figure 2 illustrates the ART 16 for a golf club assembly 12 with the upper shaft centerline 15 aligned with the golf club head 10 center of gravity 20 when the club head is drooped 22 due to swing forces. Rotation forces of the club head are illustrated by arrow 24.

[0050] As seen in Figure 3, golf clubs have a “lie” 28 which is defined as the angle between the centerline of the club’s shaft and the ground when the club is at rest on the ground. A normal driver lie angle is approximately 57 to 58 degrees, however it can be adjusted for each golfer generally between approximately 55 to 60 degrees. The lie angle 28 is important as it affects the accuracy of the shot when the club head impacts the golf ball. Bulge 29 is along the horizontal plane. Roll 31 is along the vertical plane. The planes are at right angles to each other.

[0051] As the design lie angle for most golf drivers is in the range of 57 to 58 degrees, so the lie angle becomes deformed. This is illustrated in Figure 4 with this “deformed” ART angle 30 is likely inclined to about 53 to 55 degrees relative to the sole of the club. This angle is also influenced by other variables like swing speed and shaft design stiffness and bend point as centrifugal forces are introduced during the swing.

[0052] It should be noted that the clubhead and shaft assembly can in fact only rotate about this one approximately deformed ART angle 30 from 53 to 55 degree with respect to the ART 16 which is defined by the upper portion of the shaft centerline 15 ( which is not deformed) extended at 21 through the club head center of gravity 20 relocated due to shaft deformation.

[0053] Club head rotation from off-center impact can therefore only turn the clubhead about this same ART 16 which is an approximate 53 to 55 degree axis (relative to the golf club sole), and this rotation is aligned nearly perpendicular to the ART 16 on the face as illustrated in Figure 2 as arrow 24 inclined perhaps 35 to 37 degrees clockwise from the vertical as shown by arrow 32 in Figure 4.

[0054] Among very high swing speed elite players, extraordinary composite shaft deformation has been observed through high speed photography during the forward swing and prior to impact - shaft twisting and bending of unexpected magnitude that may well exceed applicant’s 35-37 degree ranges noted above. Noteworthy, however, by the instant impact occurs, the club head orientation has been rectified to its properly squared design orientation, thereby re-establishing applicant’s ART axis of rotation.

[0055] Applicant’s invention therefore asserts a novel golf club design theory that the club head 10 only rotates (with the shaft component) about this one ART 16. Given the known and observed effects of off-center impact to both distance and direction, this should then be a foundational understanding for the design of golf clubs.

[0056] Therefore the gear effect ball spin phenomenon produced from this off-center impact should then be established perpendicular to this ART 16 thereby imparting ball spin perpendicular to this ART 16 as seen by line A - D in Figure 4 to optimize directional performance. Further, any strategies to mitigate club head rotation and / or energy transfer loss would need also to be established relative to this ART16.

[0057] One problem addressed by the invention is high toe off center impact which rotates the club head 10 clockwise and produces ART aligned counterclockwise spin. The high-toe gear effect ball spin has an axis of rotation inclined in the range of 35 to 40 degrees from the vertical and parallel to the ART 16, which is established by the deformed shaft golf club assembly 12. This 35 to 40 degree inclined ball spin axis provides resultant gear effect ball rotation that should be understood to have both horizontal and vertical ball spin components.

[0058] The horizontal ball spin component of the ART aligned gear effect sidespin introduces the observed gear-effect draw spin. But the vertical component of that ball spin also introduces the less obvious effects of overspin, effectively reducing the much larger back spin rates created by the loft at impact. The resultant high toe off-center impact produces golf ball rebound flight with a higher, right launch angle due to this club head rotation, reduced back spin from the vertical component of the ART aligned gear effect (providing flatter trajectories), and draw curvature from the horizontal component of gear effect.

[0059] Conversely, low-heel side impact rotates the club head counterclockwise and produces ART aligned ball flight changes with the opposite characteristics, namely lower launch angle, ball rebound mis-direction to the left of the intended target line, and gear effect spin increasing backspin and introducing fade ball flight curvature.

[0060] Applicant’s invention therefore concludes that face curvature shaping and its radii must be properly dimensioned and constructed perpendicular to the “club head’s” true ART 16 in order to offset gear effect ball spin properly. Applicant’s theory further concludes that the conventional design attributes for bulge and roll are in fact based upon flawed “free-body” design theory. In practice, when implementing applicant’ s invention, only one face surface curvature aligned perpendicular to the ART axis is needed.

[0061] ART ALIGNED WEIGHT DISTRIBUTION STRATEGIES

[0062] Applicant’s invention also teaches that this same ART-orientated club head rotation will benefit from ART aligned weight distribution in the golf club head for maximum MOI and energy transfer preservation during off-center impact. Therefore, designing both the golf club attributes of face curvature and weight distribution relative to this ART is essential to providing optimized golf driver accuracy and distance performance when off-center impact occurs.

[0063] Face curvature (bulge and roll) directional performance improvement has been observed for many years although not oriented or understood as described with the present invention. But hollow and multi-material club head structures have now introduced opportunities to significantly increase club head MOI for improved energy transfer preservation. Applicant's invention reveals more advanced design theory and structure now providing new and optimum understanding for how to construct these design attributes of weight distribution and face curvature.

[0064] With the present invention maximum MOI stability to preserve the greatest energy transfer (for maximized distance) and to combat club face mis-alignment from off-center impact are optimally established by concentrating mass in the club head in areas perpendicular to and maximum distances from the ART. This is accomplished by altering shape and structures and adding weight (mass) low in the heel and high in the toe on the sole of the golf club head as shown in the illustrations at locations 34 and 36 respectively which are along the axis 38 in Figure 5. Beyond the Figure 5 illustration, mass positioned maximum distances from ART 16 is most optimum.

[0065] As seen in Figure 5, applicant’s invention provides for the maximum forgiveness for energy transfer when off-center impact occurs by teaching that the weight distribution should be increased at locations high in the toe and low in the heel opposite each other and at maximum distances on a line drawn perpendicular from the true ART 16. This optimal positioning of weight relative to the ART for maximum MOI stability might be simultaneously optimized relative to the club center of gravity for optimum direct central impact launch performance. Bulge and roll axes are eliminated and replaced with a singular curvature from toe to heel perpendicular to the ART. Applicant’s face curvature is aligned perpendicular to the ART.

[0066] Implementing Applicant's teaching the following results are achieved.

[0067] 1. Off-center impact rotates the club head about the ART resulting in a changed launch angle due to this club head rotation and a resultant golf ball rebound direction altered right or left of the intended centerline relative to direct central impact launch ! rebound results.

[0068] 2. “Gear Effect” ball spin is imparted to the ball in these off-center impact cases with a ball spin axis parallel to the ART.

[0069] 3. The ball compressed on the clubface at impact is effectively “spun” with “gear effect” by the club head rotation prior to its rebound from the club face.

[0070] 4. The spin imparted to the ball is in the opposite directions of the club head rotation, but this novel orientation of the gear effect ball spin / club head rotation is now accordingly oriented with rotational axes parallel to the ART

[0071] 5. Implementing the ART aligned club head rotational theory obviates the need for two separate conventional “bulge and roll” curvatures as found in most conventional golf club designs to provide the needed Gear Effect management for ball flight directional corrections. They are instead replaced with a single convexly curved face surface roughly aligned from low in the heel to high in the toe. By adding or removing convex curvature to the face of the club head and perpendicular to the ART we can manage gear effect.

[0072] 6. By providing mass (weight additions) at locations high in the toe and low in the heel and at maximum distances perpendicular from the true ART, we provide for the maximum forgiveness for energy transfer when off-center impact occurs. This positioning of mass relative to the ART for maximum MOI stability may also provide for optimum direct central impact launch performance.

[0073] Thus there has been provided a golf club driver assembly that increases accuracy and distance that better forgives and mitigates the effects of off-center impact as compared to prior art drivers utilizing the concepts taught in this application. While the invention has been described in conjunction with a specific embodiment, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications and variations as fall within the spirit and scope of the appended claims.

Claims

What is claimed is:

1. A golf driver with means for improving distance and accuracy performance during off-center impacts comprising: a. a golf club assembly comprising a golf club head having a toe and heel, a shaft, and a grip mounted on the shaft, the golf club assembly rotating about a single axis of rotation during off-center impact, and having a striking club face surface that is substantially perpendicular to the desired target line and has a convex face curvature surface; b. placement of mass in the golf club head on a line perpendicular to the single axis of rotation for the golf club assembly; c. orientation of the convex face curvature surface of the club head for management of gear effect side spin for optimized accuracy relative to the single axis of rotation for the golf club assembly; whereby off-center impact on said club head will rotate the club head about the single axis of rotation.

2. The golf driver of claim 1 wherein the mass is positioned in the golf club head low in the heel and high in the toe of the golf club head.

3. The golf club driver of claim 1 wherein the convex face curvature surface follows a curve approximately perpendicular to the axis of rotation.

4. The golf club driver of claim 3 wherein the convex face curvature surface has its curvature alignment orientation generally from low in the heel to high in the toe of the golf club head.

5. The golf club driver of claim 4 wherein the convex face curvature is rotated approximately 35 to 40-degrees clockwise from a vertical axis viewed from down the target line for right-handed golf club heads and aligned perpendicular to the single axis of rotation.

6. The golf club driver of claim 5 wherein the axis of rotation being a line created during club impact with the golf ball extending from the center of the upper portion of the shaft through the center of the club head and offset between an angle of 52 degrees to 56 degrees from a club head lie angle of 57-58 degrees.

7. A method for designing a golf driver comprising the steps of: a. selecting a shaft and grip suitable for a given golfer golfer; b. selecting a golf club head of hollow construction and conventionally shaped with a partially flattened vertically disposed forward striking surface as prescribed by the rules of golf; c. determining the angle of deformation of the golf club head during the golf club swing; d. determining a single axis of rotation for the club head during off-center impacts, the single axis of rotation being a line extending from an upper portion centerline of the shaft through the golf club head center of gravity during the dynamic deformation caused by off center impact; e. imparting a forward convex surface to the forward striking surface, the forward convex surface having a curvature alignment from low in the heel to high in the toe.

8. The method of claim 7 and the further step of adding mass to the golf club head low in the heel and high in the toe and perpendicular to the single axis of rotation while remaining within the volumetric and moment of inertia limitations prescribed by the rules of golf.

9. The method of claim 8 and further orienting the curvature alignment of the convex surface from low in the heel to high in the toe such that it is rotated approximately 35 to 40-degrees clockwise from a vertical axis viewed from down the target line and aligned perpendicular to the single axis of rotation.

10. The method of claim 8 and the further step of attaching the shaft to the golf club head.

11. The method of claim 8 and the further step of orienting the convex surface of said club head relative to the single axis of rotation for management of gear effect side spin.

12. The method of claim 8 and the further step of adding mass done by shaping or altering materials or material thicknesses to the golf club head.

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