Golf clubhead and method of manufacturing the same

A method of making a golf clubhead,

• containing a main body and a face member, the main body including a main shell portion having a hollow and a tubular inner extension of a hosel protruding in the hollow, and at least a part of the tubular inner extension separating from the inner surface of the main shell portion, said method comprising:
• making a first lost form corresponding to the main shell portion;
• making a second lost form corresponding to the tubular inner extension;
• fixing the second lost form to the first lost form to make a third lost form corresponding to the main body;
• making a casting mold using the third lost form;
• and casting a metallic material into the main body using the casting mold wherein the main body is provided between the tubular inner extension and the inner surface of the main shell portion with a bridge, the bridge having a thickness less than an outer diameter of the tubular inner extension and a total length less that the length of the tubular inner extension.

A method of making a component of a golf clubhead comprising

• dividing the component into a first piece having a hole and a second piece having a hole,
• making a first lost form corresponding to the first piece,
• making a second lost form corresponding to the second piece,
• combining the first lost form and second lost form into a third lost form corresponding to said component, inserting a round bar into a hole of the first lost form and a hole of the second lost form, the round bar made of a material same or similar to a casting mold,
• making the casting mold using the third lost form with said round bar, and
• casting a metallic material into said component using the casting mold.

A method of making a gold clubhead,

• The golf clubhead comprising a main body and a face member, the main body comprising a main shell portion having a hollow and a tubular inner extension of a hosel protruding in the hollow, and at least a part of the tubular inner extension separating from the inner surface of the main shell portion,
• the method comprising:
• making a first lost form corresponding to the main shell portion;
• making a second lost form corresponding to the tubular inner extension;
• fixing the second lost form to the first lost form to make a third lost form corresponding to the main body;
• making a casting mold using the third lost form;
• and
• casting a metallic material into the main body using the casting mold so that the main body has a single piece structure and the separating part of the tubular inner extension has a length (L1) of from 20 to 38 mm.