Golf club shaft and process of preparing same

A process for the preparation of a golf club shaft, comprising the steps of:

• providing an axially elongated mandrel having an outer diameter gradually increasing from one end thereof to the other end thereof;
• winding at least one sheet of a first prepreg, containing uniaxially oriented reinforcing fibers each having a modulus of 20,000 kgf/mm.sup.2 and a tensile strength of 500 kgf/mm.sup.2 or more and dispersed within a matrix of a first hardenable resin, around said mandrel to form a first wound layer axially extending from a first portion of said mandrel adjacent to said one end to a second portion of said mandrel 50-500 mm away from said first portion with said reinforcing fibers being oriented at an angle in the range of 0 to 5 degrees with respect to the axis of said mandrel;
• winding at least one sheet of a second prepreg, containing uniaxially oriented first carbon fibers each having a modulus of 29,000 kgf/mm.sup.2 or more and a tensile strength of 300 kgf/mm.sup.2 or more and dispersed within a matrix of a second hardenable resin, around said mandrel to form a second wound layer axially extending from said first portion of said mandrel to a third portion of said mandrel adjacent to said the other end thereof with said first carbon fibers being oriented at an angle in the range of 40 to 50 degrees with respect to the axis of said mandrel;
• then hardening said first and second wound layers so that a reinforcing layer of the hardened first resin reinforced with said reinforcing fibers and an inner layer of the hardened second resin reinforced with said first carbon fibers are formed around said mandrel;
• then winding a roving of second carbon fibers each having a modulus of 24,000 kgf/mm.sup.2 and a tensile strength of 450 kgf/mm.sup.2 or more and impregnated with a third hardenable resin around said inner layer to form a third wound layer extending to entirely cover said inner layer with said second carbon fibers being oriented at an angle in the range of 5 to 30 degrees with respect to the axis of said mandrel;
• then hardening said third wound layer to form an outer layer of the hardened third resin reinforced with said second carbon fibers and to thereby form an integral assembly composed of said reinforcing layer, said inner layer and said outer layer;
• and
• removing said mandrel from said assembly.