A shim or badge is affixed to a golf club body to produce a cap-back iron, giving the appearance of a hollow-body iron. In this way, the golf club can be manufactured with the performance benefits of a game improvement iron, while providing the appearance of a blade, player's iron, and/or a hollow-body iron. For example, by using a lightweight and rigid shim or badge to close a cavity opening and extend into the toe portion in the golf club body, the golf club head can provide increased stiffness in the topline, while lowering CG. Various shim or badge arrangements and materials can be used, and a filler material and/or damper can be included within the cavity to improve sound and feel, while minimizing loss in COR.

Disclosed herein is a golf club head that comprises a body. The body comprises a sole portion, a crown portion, a skirt portion, and a face portion, positioned at a forward region of the golf club head, opposite a rearward region of the golf club head, and extending from a toe region to a heel region of the golf club head. At least a portion of the body is made of a titanium alloy. The golf club head also comprises a large weight, coupled to the sole portion of the body and made of a steel alloy. A mass of the large weight is at least 40% of a mass of the portion of the body made of the titanium alloy. A total mass of the large weight and the portion of the body made of the titanium alloy is at least 210 grams.

A golf club head that is capable improving on the inertia properties of a golf club head all while also improving the Center of Gravity (CG) location is disclosed herein. More specifically, the golf club head in accordance with the present invention achieves a relative low Moment of Inertia (MOI) about the Z-axis (MOI-Z) as well as a relatively low MOI about the Shaft-axis (MOI-SA), all combined with a high MOI about the X and Y-axis (MOI-X and MOI-Y) and maintaining a consistently and relatively low CG location measured along a direction tangent to the hosel axis along the X-Y plane (CG-B).

A golf club head that is capable improving on the inertia properties of a golf club head all while also improving the Center of Gravity (CG) location is disclosed herein. More specifically, the golf club head in accordance with the present invention achieves a relative low Moment of Inertia (MOI) about the Z-axis (MOI-Z) as well as a relatively low MOI about the Shaft-axis (MOI-SA), all combined with a high MOI about the X and Y-axis (MOI-X and MOI-Y) and maintaining a consistently and relatively low CG location measured along a direction tangent to the hosel axis along the X-Y plane (CG-B). The golf club head includes a frontal portion and a rear portion which may be secured together with rotational motion.

A resilient face insert for a golf club head, preferably a putter head, is disclosed herein. In particular, the face insert comprises a plurality of hinge features spaced from a striking surface to ensure consistent ball speed across the striking surface. At least a portion of each hinge feature extends parallel to the striking surface without making contact with the striking surface. In the preferred embodiment, each hinge feature comprises a tab portion that is spaced from the striking surface by a stem portion and that extends parallel to the striking surface. The hinge features may be co-molded with a polymeric backing material in order to further improve performance of the face insert.

Disclosed herein is a casting cluster for casting a body of a golf club head made of titanium or a titanium alloy. The casting cluster comprises a receptor and a plurality of runners coupled to the receptor and configured to receive molten metal from the receptor. The casting cluster also includes at least twenty-eight main gates. At least two of the main gates are coupled to each of the runners and each main gate is configured to receive molten metal from a corresponding one of the plurality of runners. The casting cluster further comprises at least twenty-eight molds. Each mold of the at least twenty-eight molds is configured to receive molten metal from a corresponding one of the main gates and to cast a body of a golf club head that has a volume of at least 100 cm.sup.3.

Methods of manufacturing a golf club head comprising one or more stiffening members proximate the face, and particularly solid rods or a plate with one or more cutouts, is disclosed herein. One method comprises the steps of preparing a wax mold of a golf club head including a plate stiffening member with excess material, casting the golf club head, and machining away the excess material. Another method comprises the steps of casting a golf club body, providing a plate stiffening member, providing a face component such as a face cup, tack welding the plate stiffening member and the face component to the golf club body, and welding these parts together.

An underwater training apparatus is disclosed. The underwater training apparatus may include a barrel. The barrel may contain a plurality of holes disposed across the barrel. Each of the holes of the barrel may pass through a wall of the barrel. The underwater training apparatus may also include a base funnel. The base funnel may contain a plurality of holes disposed across the base funnel. Each of the holes of the base funnel may pass through a wall of the base funnel. The underwater training apparatus may also include a handle. The handle may mechanically couple the barrel and the base funnel.

Disclosed herein is a golf club head comprising at least one crown opening and at least one crown insert attached to the body and covering the at least one crown opening. The golf club head further comprises at least one sole opening and at least one sole insert attached to the body and covering the at least one sole opening. The golf club head additionally includes at least one weight member configured to clamp first and second ledges at selected locations along a sliding weight track. The golf club head also comprise a coefficient of restitution (COR) feature located on the sole of the golf club head. The at least one crown insert is formed from a composite material having a density between 1 g/cc and 2 g/cc. The at least one sole insert is formed from a composite material having a density between 1 g/cc and 2 g/cc.

Disclosed herein is a golf club head comprising at least one crown opening and at least one crown insert attached to the body and covering the at least one crown opening. The golf club head further comprises at least one sole opening and at least one sole insert attached to the body and covering the at least one sole opening. The golf club head additionally includes at least one weight member configured to clamp first and second ledges at selected locations along a sliding weight track. The golf club head also comprise a coefficient of restitution (COR) feature located on the sole of the golf club head. The at least one crown insert is formed from a composite material having a density between 1 g/cc and 2 g/cc. The at least one sole insert is formed from a composite material having a density between 1 g/cc and 2 g/cc.