Abstract: A golf club shaft used with putter type club heads for making a putting stroke on the green of a golf course is made from high-modulus fibers which results in an ultra-high stiffness putter shaft with high frequency, low tip deflection, and high torsional and bending rigidity. The ultra-high stiffness putter shaft prevents unwanted face twisting during the impact of a golf ball during a putting stroke, allowing for greater putt accuracy.

Abstract: Described herein is a golf club shaft used with putter type club heads for making a putting stroke on the green of a golf course. The putter shaft is made from high-modulus fibers which results in an ultra-high stiffness putter shaft with high frequency, low tip deflection, and high torsional and bending rigidity. The ultra-high stiffness putter shaft prevents unwanted face twisting during the impact of a golf ball during a putting stroke, allowing for greater putt accuracy.

Abstract: The method of producing tubular golf club shafts (10) of the same longitudinal stiffness and varying weights by wrapping composite materials on a tapered mandrel (15), or mandrels, having a given taper profile, producing a core (30) of angle-fiber-and-resin material and a shell (31) of longitudinal-fiber-and-resin material, and varying the weight of the cores to vary the shaft weight while maintaining the core size and the shell size the same. This is accomplished by moving the core along a taper profile to compensate for the change in the amount of material, thus maintaining the longitudinal stiffness/bending profile the same in the shafts of greatly varying weight. A representative family of shafts (10) has nominal weights of 55, 65, 75, 85, 95 and 105 grams, with the same stiffness/bending profile.

Abstract: Apparatus and method for locating the neutral bending plane of an elongated flexible shaft, typically a golf club shaft, by mounting one end portion of the shaft in a clamping mechanism having a rotatable clamp member that permits the shaft to turn about its longitudinal axis while being driven through a motion simulating a golf swing, with sufficient speed to cause the inertial loading of the shaft by its own mass, enhanced by a head weight, to turn the clamp member and the shaft into alignment with the path of movement of the shaft during the simulated swing. A brake fixes the shaft in this position during the swinging motion. A first embodiment uses a rotary motor to rotate the shaft in a radially projecting position about a stationary axis, with a clamping mechanism and brake mechanism on a base plate mounted on the motor shaft.

Abstract: Apparatus and method for locating the neutral bending plane of an elongated flexible shaft, typically a golf club shaft, by mounting one end portion of the shaft in a clamping mechanism having a rotatable clamp member that permits the shaft to turn about its longitudinal axis while being driven through a motion simulating a golf swing, with sufficient speed to cause the inertial loading of the shaft by its own mass, enhanced by a head weight, to turn the clamp member and the shaft into alignment with the path of movement of the shaft during the simulated swing. A brake fixes the shaft in this position during the swinging motion. A first embodiment uses a rotary motor to rotate the shaft in a radially projecting position about a stationary axis, with a clamping mechanism and brake mechanism on a base plate mounted on the motor shaft.

Abstract: A flex-segmented golf club shaft having tip and butt sections of preselected stiffness and flex characteristics, respectively, that are formed as separate pieces, with the larger butt section overlapping and fused to the smaller tip section and forming an external step in the shaft profile. An alternative embodiment has three such sections and two steps. The method of forming the shaft by wrapping a preselected tip section from a selection of available sections on a mandrel having a pronounced step, and then wrapping a preselected butt section from a selection of available sections on the mandrel in overlapping relation with the tip section, to provide optimized characteristics for a particular golf swing.