A forged golf club face has a continuous outer layer of a first material encasing at least one inner layer made of second material. The materials may have differing properties, such as Young's Modulus, density, and strength properties, among others. By incorporating the different materials into the outer layer and the inner layer, the coefficient of restitution (COR) of the golf club face is improved without sacrificing durability. The club face is forged from a pre-formed billet having at least one monolithically encased inner layer.

A forged golf club face has a continuous outer layer of a first material encasing at least one inner layer made of second material. The materials may have differing properties, such as Young's Modulus, density, and strength properties, among others. By incorporating the different materials into the outer layer and the inner layer, the coefficient of restitution (COR) of the golf club face is improved without sacrificing durability. The club face is forged from a pre-formed billet having at least one monolithically encased inner layer.

Provided is a method for manufacturing an iron golf club head by forging a single round rod member with a pair of dies to form, as a single piece, a body and a neck into which a shaft is to be inserted. The method includes: a first step of heating the single round rod member into a heated material; a second step of placing the heated material in the pair of dies; and a third step of forging the heated material placed in the pair of dies. In the third step, the heated material is prevented from flowing out from parting surfaces of the respective dies at a sole side of the body in the pair of dies, and the heated material blocked at the sole side in the pair of dies flows toward each of a toe of the body and the neck in the pair of dies.

Provided is a method for manufacturing an iron golf club head by forging a single round rod member with a pair of dies to form, as a single piece, a body and a neck into which a shaft is to be inserted. The method includes: a first step of heating the single round rod member into a heated material; a second step of placing the heated material in the pair of dies; and a third step of forging the heated material placed in the pair of dies. In the third step, the heated material is prevented from flowing out from parting surfaces of the respective dies at a sole side of the body in the pair of dies, and the heated material blocked at the sole side in the pair of dies flows toward each of a toe of the body and the neck in the pair of dies.

A golf club head includes a metallic section, a polymeric section, and an adhesive material. The metallic section defines an opening and the polymeric section extends over the opening. The adhesive material is disposed between the metallic section and the polymeric section to form an adhesive joint therebetween. The adhesive joint has an adhesive retaining strength configured to inhibit the polymeric section from being detached from the metallic section when the adhesive material is at least partially cured. The metallic section and the polymeric section are also mechanically engaged with one another to form a mechanical joint therebetween having a mechanical retaining strength configured to inhibit the polymeric section from being detached from the metallic section. The adhesive retaining strength of the adhesive joint, alone, is greater than the mechanical retaining strength of the mechanical joint, alone, only when the adhesive material is at least partially cured.

A method of manufacturing a golf club head comprising a plurality of stiffening members proximate the face, and particularly solid rods or a plate with one or more cutouts, is disclosed herein. The method comprises the steps of preparing a wax of a golf club head body, the body comprising at least one through-holes, a hollow interior, and at least one receiving pocket, preparing waxes of one or more stiffening members, inserting the wax of the stiffening members into the through-hole and seating its opposite end in the receiving pocket, bonding each of the stiffening members to the body with an adhesive material to form a combined wax mold, and casting a golf club head from the combined wax mold.

A method of manufacturing a golf club head comprising a plurality of stiffening members proximate the face, and particularly solid rods or a plate with one or more cutouts, is disclosed herein. The method comprises the steps of preparing a wax of a golf club head body, the body comprising at least one through-holes, a hollow interior, and at least one receiving pocket, preparing waxes of one or more stiffening members, inserting the wax of the stiffening members into the through-hole and seating its opposite end in the receiving pocket, bonding each of the stiffening members to the body with an adhesive material to form a combined wax mold, and casting a golf club head from the combined wax mold.

A method for manufacturing a bicycle crank is revealed. After being extended, bent and forged, an aluminum alloy pipe becomes an L-shaped part formed by a cylindrical crankshaft portion and an oval crank portion integrally connected to each other. A plug is inserted into an outer end of the crank portion while a periphery of an outer end of the crankshaft portion is punched to form a shaft-connecting portion. An assembling hole is arranged at the outer end of the crank portion, corresponding to the plug. Thus a bicycle crank is produced. Thereby not only the assembly of the bicycle crank is easier and more convenient, the structural strength of the bicycle crank is increased effectively to against vibrations and impacts. The bicycle is lightweight and the bicycle crank is more streamlined so that consumers are attracted. Thereby the market competitiveness is increased.

A method for manufacturing a bicycle crank is revealed. After being extended, bent and forged, an aluminum alloy pipe becomes an L-shaped part formed by a cylindrical crankshaft portion and an oval crank portion integrally connected to each other. A plug is inserted into an outer end of the crank portion while a periphery of an outer end of the crankshaft portion is punched to form a shaft-connecting portion. An assembling hole is arranged at the outer end of the crank portion, corresponding to the plug. Thus a bicycle crank is produced. Thereby not only the assembly of the bicycle crank is easier and more convenient, the structural strength of the bicycle crank is increased effectively to against vibrations and impacts. The bicycle is lightweight and the bicycle crank is more streamlined so that consumers are attracted. Thereby the market competitiveness is increased.

A golf club head has an inner cavity and comprises a face member and a head main body which a front opening, which are connected to each other. The head main body comprises a sole portion, and a weight member which has a specific gravity greater than that of the head main body is fixed to an inner surface of the sole portion. A weld which fix the weight member to the sole portion is disposed at the peripheral edge of the weight member. The weight member has the width in the toe-heel direction of the head, which is smaller on its rear side than its front side.