A hybrid golf club shaft set is provided that includes a composite shaft subset including shafts formed entirely of composite, a composite/metal shaft subset including shafts formed of composite/metal combination shafts, and a metal shaft subset including shafts formed entirely of metal. The composite shaft subset preferably includes the long irons with the lowest lofts such as the two, three, and four iron shafts. The composite/metal shaft subset preferably includes the middle irons with medium lofts such as the five, six, and seven iron shafts. The metal shaft subset preferably includes the short irons with the highest lofts such as the eight, nine, and wedge shafts.
The present invention relates to methods for optimizing the flexibility of each shaft comprised in a set of golf clubs. In general, based on a golfer's estimated swing speed, skill level and/or other relevant factors, an appropriate category of golf club shafts is selected. Each category of golf club shafts employ a unique range of shaft flexibility. The range of flexibility exhibited by categories of golf club shafts optimized for golfers with relatively higher swing speeds is greater than the range of flexibility exhibited by categories of golf club shafts optimized for golfers with relatively slower swing speeds. Similarly, the range of flexibility exhibited by categories of golf club shafts optimized for golfers of relatively higher skill levels is greater than the range of flexibility exhibited by categories of golf club shafts optimized for golfers of relatively lower skill levels.
A device for coupling two shaft members of differing diameters. The device includes a barrel and a reaction mass. The barrel is hollow and includes an outside coupler formed by the exterior surface of an upper portion of the barrel, an inside coupler formed by the inside surface of the barrel, and a reaction mass interface formed by the exterior surface of a lower portion of the barrel. The outside coupler is sized to fit inside a hollow end of the first shaft member. The inside coupler is sized to receive the second shaft member. The reaction mass slides over the second shaft member and into position on the reaction mass interface of the barrel. The parts are secured together with an adhesive.
Lightweight articles comprising a polymeric material at least partially coated with a fine-grained metallic material are disclosed. The fine-grained metallic material has an average grain size of 2 nm to 5,000 nm, a thickness between 25 micron and 5 cm, and a hardness between 200 VHN and 3,000 VHN. The lightweight articles are strong and ductile and exhibit high coefficients of restitution and a high stiffness and are particularly suitable for a variety of applications including aerospace and automotive parts, sporting goods, and the like.
Lightweight articles comprising a polymeric material at least partially coated with a fine-grained metallic material are disclosed. The fine-grained metallic material has an average grain size of 2 nm to 5,000 nm, a thickness between 25 micron and 5 cm, and a hardness between 200 VHN and 3,000 VHN. The lightweight articles are strong and ductile and exhibit high coefficients of restitution and a high stiffness and are particularly suitable for a variety of applications including aerospace and automotive parts, sporting goods, and the like.
