Embodiments of golf club heads and methods to manufacture golf club heads are generally described herein. In one example, a golf club head may include a first body portion being hollow to define an interior cavity, a first body portion recess on a back wall portion below a horizontal midplane of the first body portion, and a second body portion removably coupled to the first body portion in the first body portion recess. The golf club head may include at least one fastener configured to fasten the second body portion to the first body portion, and a face portion having a back surface opposite the front surface and associated with a total back surface area. The back surface may include first back surface region associated with a first back surface area and coupled to a front portion of the first body portion. The face portion may include a second back surface region exposed to the interior cavity and associated with a second back surface area. The total back surface area may be equal to a sum of the first back surface area and the second back surface area, and the first back surface area may be less than 30% of the total back surface area. Other examples and embodiments may be described and claimed.

Described herein is a hollow body iron-type golf club head having a sole and ballast configured to relieve stress within a forward portion of the sole. In a first configuration, the golf club head comprises a ballast undercut for relieving stress. In other configurations, the ballast undercut is combined with additional stress relief features, such as a cascading sole near the face sole juncture, for further reductions to face thickness.

A shim or badge is affixed to a golf cub 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.

Embodiments of golf club heads, golf clubs, and methods to manufacture golf club heads and golf clubs are generally described herein. In one example, a golf club head may include a body portion including an interior cavity, a filler material in the interior cavity, and a face portion having a front surface, a back surface, a face perimeter defined by a face toe edge, a face heel edge, a face top edge, and a face sole edge. The face portion may further include a first back groove portion on the back surface located proximate to the face toe edge and extending from a location at or proximate to the face top edge toward the face sole edge, a second back groove portion on the back surface located proximate to the face top edge and extending from a location at or proximate to the face toe edge to a location at or proximate to the face heel edge, and a third back groove portion on the back surface located proximate to the face heel edge and extending from a location at or proximate to the face top edge toward the face sole edge. The first back groove portion and the second back groove portion, or the second back groove portion and the third back groove portion may be connected. The first back groove portion, the second back groove portion, and the third back groove portion may be at least partially filled with the filler material. Other examples and embodiments may be described and claimed.

Embodiments of golf club heads and methods to manufacture golf club heads are generally described herein. In one example, a set of golf club heads includes a plurality of golf club heads with ach golf club head having a distinct loft angle ranging from 19.5° to 47°. Each golf club head produces a loudness as a result of striking a golf ball at a predetermined golf club head speed. The loudness is in sone units and is based on a sound pressure measurement performed at a predetermined sampling rate and taken for a fixed duration of time with a microphone placed directly above the golf ball at a fixed vertical distance. For a golf club head speed of 80 mph, the loudness of each golf club head ranges from 82.58 to 92.76 sones and is inversely related to loft angle. For a golf club head speed of 85 mph, the loudness of each golf club head ranges from 86.85 to 97.07 sones and is inversely related to loft angle. For a golf club head speed of 90 mph, the loudness of each of golf club head ranges from 92.90 to 101.82 sones and is inversely related to loft angle. Other examples and embodiments may be described and claimed.

Embodiments are described herein of a bifurcated heat treatment apparatus and methods for localized heat treatment of a golf club hosel or golf club head. The heat treating method comprises a bifurcated process in which the golf club head is treated in the first heating unit via induction heating and then moved to the second heating unit for convection heating. Both steps are to localize the hosel heat treatment. The heat treatment apparatus may also include a cooling component, such as a heat sink, to ensure the body of the club head remains at the correct temperature during the second heating stage when the hosel is heated in isolation. The overall bifurcated method and apparatus of the localized heat treatment leads to a hosel or golf club head with at least two different hardness values to allow for manipulation of the material without cracking or fracturing.

Embodiments of a golf club head comprising a body having a body material density, a strike face having a strike face material density, and a coating comprising a coating material having a coating material density greater than the body material density or the strike face material density are described herein.

Embodiments of golf club heads and methods to manufacture golf club heads are generally described herein. In one example, a golf club head may have a body portion having a toe portion, a heel portion, a top portion, a sole portion, a front portion, a lead edge portion, a back portion, and an interior cavity. The golf club head may also have a polymer material partially or entirely filling the interior cavity. Other examples and embodiments may be described and claimed.

A golf club has a first shaft coupled to a club head, a second shaft configured to slidably engage a portion of the first shaft, a grip coupled to the second shaft, and an adjustable length shaft assembly received by the second shaft and configured to allow a portion of the first shaft to slide in relation to the second shaft in a first configuration, and to restrict a portion of the first shaft from sliding in relation to the second shaft in a second configuration. The grip is restricted from rotation about the first shaft or the second shaft as the first shaft slides in relation to the second shaft.

An iron-type golf club head incudes a body, a recessed channel, and a weight assembly. The body includes a striking face, a sole, and a back portion positioned between the sole and the striking face. The recessed channel is formed in the back portion. The weight assembly includes a weight at least partially disposed within the recessed channel and configured to move therein, a cover, and a fastener coupling the cover to the body and configured to retain the weight in the recessed channel indirectly by the cover.