An assembly jig comprises a platform, first and second parallel posts projecting from the platform, and a pillar projecting from the platform in a position equidistant from each of the posts and forward of an imaginary line between the posts such that the posts and the pillar are in a triangular arrangement. The pillar is shorter than the posts.

Examples of golf clubs and methods to manufacture golf clubs are generally described herein. In one example, a golf club may include a golf club head, a hosel portion, and a shaft. The hosel portion may be positioned rearward of a center of gravity of the body portion. The shaft portion may be coupled to the hosel portion and may have a first shaft portion and a second shaft portion. The first shaft portion may extend from the hosel portion and tilt toward the face portion with no lateral tilt toward a toe portion or a heel portion of the body portion. The second shaft portion may extend from the first shaft portion toward the heel portion and toward a face portion of the body portion. Other examples of golf club heads and methods to manufacture the same may be described and claimed.

A golf club head includes a striking face having a face center and defining a face plane. A vertical center plane is perpendicular to the face plane and passes through the face center. The golf club head further includes a hosel configured to receive a shaft and defining a hosel axis. The golf club head mass is between about 250 g and 320 g, a loft, L, is no less than 39°, a club head center of gravity is spaced rearward from the face plane by a distance, D5, such that D5≤7.69 mm−0.074 mm/°*L, and spaced from the vertical center plane by a distance, D7, that is no greater than 5 mm. A moment of inertia, Iyy, measured about an axis extending in the heel to toe direction and passing through the center of gravity, is no less than 1000 g*cm.sup.2.

A laser mandrel system that self-centers within a hosel bore of a golf club head to allow for precision adjustment of lie and loft is disclosed herein. The mandrel includes a one-piece housing with upper and lower portions, a laser centered within the upper portion of the housing, and a plurality of o-rings extending around an exterior or interior surface of a lower portion of the housing.

A laser mandrel system that self-centers within a hosel bore of a golf club head to allow for precision adjustment of lie and loft is disclosed herein. The mandrel includes a one-piece housing with upper and lower portions, a laser centered within the upper portion of the housing, and a plurality of o-rings extending around an exterior or interior surface of a lower portion of the housing.

Embodiments of putter-type golf club heads with adjustable loft and lie and methods of manufacturing of the same with adjustable loft and lie are generally described herein. These embodiments relate in particular to a putter-type club head with an adjustment portion that allows a user to change the loft and lie. The separate adjustment portions of the putter-type club head can couple the upper hosel to the body at a plurality of positions. An insert part of the adjustment portion has an upper section for receiving the upper hosel portion, a middle section, and a lower hosel portion. The sections of the adjustment portion can be coupled together by a fastener so that the sections are rotationally movable.

Embodiments of putter-type golf club heads with adjustable loft and lie and methods of manufacturing of the same with adjustable loft and lie are generally described herein. These embodiments relate in particular to a putter-type club head with an adjustment portion that allows a user to change the loft and lie. The separate adjustment portions of the putter-type club head can couple the upper hosel to the body at a plurality of positions. An insert part of the adjustment portion has an upper section for receiving the upper hosel portion, a middle section, and a lower hosel portion. The sections of the adjustment portion can be coupled together by a fastener so that the sections are rotationally movable.

Embodiments of a co-molded putter-type golf club head comprising a high-density chassis made of a first material and a low-density putter-type body made of a second material. The first material can be a high density metal (i.e., steel or tungsten, but not limited to). The second material can be a low density thermoplastic composite (i.e., polyphenylene sulfide (PPS), polyamide (PA), but not limited to). The chassis comprises a flow aperture, and one or more interlocking features. The putter-type body portion encases the entirety of the at least one interlocking feature. Further, the putter-type body encapsulates the chassis such that the body extends through, and completely fills the flow aperture, to interlock the body and chassis, and thus form the club head. Other embodiments may be described and claimed.

Embodiments of a co-molded putter-type golf club head comprising a high-density chassis made of a first material and a low-density putter-type body made of a second material. The first material can be a high density metal (i.e., steel or tungsten, but not limited to). The second material can be a low density thermoplastic composite (i.e., polyphenylene sulfide (PPS), polyamide (PA), but not limited to). The chassis comprises a flow aperture, and one or more interlocking features. The putter-type body portion encases the entirety of the at least one interlocking feature. Further, the putter-type body encapsulates the chassis such that the body extends through, and completely fills the flow aperture, to interlock the body and chassis, and thus form the club head. Other embodiments may be described and claimed.

A golf club head including a striking face, a sole extending aft from the striking face, a crown extending aft from the striking face, a skirt extending between the sole and the crown, an interior cavity defined by the striking face, the sole, the crown, and the skirt, an aperture formed through the sole, the aperture having an aperture length and an aperture width, wherein the aperture length is substantially larger than the aperture width, and a stiffening member affixed to the sole, wherein a portion of the stiffening member resides within the aperture, wherein the sole is constructed of a first material having a first density, the stiffening member is constructed of a second material having a second density, and wherein the second density is at least 30% less than the first density.