Abstract: A golf club set which comprises a plurality of golf clubs having shafts of different tapered section lengths, at least two golf club shafts of the set having differing taper lengths and preferably differing taper angles, the tapered section length of the shaft increases as the shaft length increases for each club throughout the set, and vice versa. Accordingly, each shaft throughout the set of shafts has a distinct taper length. The distinct variable taper clubs provide efficient energy transfer, better feel perception by the golfer, greater ball flight distance, less ball flight dispersion, and greater club stability.

Abstract: A golf club set which comprises a plurality of golf clubs having shafts of different tapered section lengths, at least two golf club shafts of the set having differing taper lengths and preferably differing taper angles, the tapered section length of the shaft increases as the shaft length increases for each club throughout the set, and vice versa. Accordingly, each shaft throughout the set of shafts has a distinct taper length. The distinct variable taper clubs provide efficient energy transfer, better feel perception by the golfer, greater ball flight distance, less ball flight dispersion, and greater club stability.

Abstract: A tubular blank for producing golf club shafts comprises a butt section having a uniform cross-sectional configuration along its length, a tip section also having a uniform cross-sectional configuration along its length, and a tapered section interconnecting the butt and tip sections. Metallurgically formed rifling on the interior surface of the blank extends throughout the entirety of the butt, tip and tapered sections. The golf club shafts produced from these blanks have increased strength and stiffness which is a direct result of the interior rifling. A set of golf club shafts preferably is produced from a group of these tubular blanks with each blank of the group having the same length and the same natural frequency. Predetermined portions are then selectively removed from the tip and butt sections.

Abstract: A golf ball striking device has a framework with a club and shaft assembly rotatably mounted to the framework for movement along a swing path in a first vertical plane. A golf ball tee assembly is also rotatably mounted to the framework for free movement in a second vertical plane into any one of a plurality of positions, and structure is provided for releasability locking the golf ball tee assembly in place at the selected position. A golf ball tee is located at the outer end of the golf ball tee assembly for holding a golf ball in the first vertical plane in the swing path of the club and shaft assembly. A structural arrangement on the golf ball tee assembly maintains the tee vertical at any of the plurality of positions of the golf ball tee assembly. A motivator is connected to move the club and shaft assembly along its swing path for striking a golf ball on the tee.

Abstract: A special purpose calculator for determining the optimum degree of flexibility for a matched set of golf clubs, tailored to the driving capability of the individual golfer. The calculator first correlates the effective driving capability of the individual to an empirically determined optimum flexibility index, which index is based on a standard club length, hosel length, tip insertion depth, and swing weight of the golf club. The calculator next compensates for desired differences, in for example club length and swing weight, to determine a shaft with a compensated flexibility index which will provide the same "feel" as the standard club. The calculator can then also be used to determine the requisite head weights, both wood and iron, as a function of desired club length and swing weight so as to provide the proper flexibility for that individual. For optimum results, the flexibility index is determined by measuring the vibration frequency of the shaft.

Abstract: Method of producing variety of golf club shafts from universal blank shaft of given length includes steps of determining actual natural frequency of blank shaft. Selected amounts of shaft length are then removed from both tip and butt end portions of blank in correlation with natural frequency of blank. Total amount removed from blank solely depends upon length of shaft desired while selected amounts removed from tip and butt end portions of blank solely depend upon natural frequency of shaft desired. As proportional amount removed from tip portion increases, frequency of produced shaft also increases. Conversely, as proportional amount removed from tip portion decreases, frequency of produced shaft also decreases.

Abstract: Method of producing matched golf clubs comprises steps of determining under similar conditions frequency of each golf club shaft of plurality of shafts. Shafts are selected from plurality such that frequencies thereof fall on predetermined gradient formed by plot of shaft frequency and shaft length. Frequency increments between successive shaft lengths along gradient are substantially equal. Subsequent mating of shafts with selected club heads produces integrated and correlated matched golf clubs. Matched set of shafts and clubs is also described.