Apparatus for producing fastener assembly with molded internal helical flutes

An apparatus for use in a mold, comprising:

• a pin including a lower end and an upper end;
• a pin shoulder proximate the lower end of the pin;
• at least one helical groove at the upper end of the pin;
• a sleeve disposed about a portion of the pin;
• means for allowing the pin to rotate within and independent of the sleeve.

A method of molding, comprising the steps of:

• providing a mold defining a cavity and a shaft proximate the cavity;
• inserting a pin assembly into the shaft, wherein the pin assembly includes a pin comprising a grooved portion defining at least one helical groove, a sleeve disposed about a portion of the pin, and means to allow rotation of the pin;
• forming a gap between a portion of the walls of the shaft and the grooved portion of the pin;
• sealing at least a portion of the gap with a portion of the sleeve;
• injecting molten polymer into the cavity and the gap;
• cooling the polymer;
• and
• moving the sleeve in the direction of the gap, thereby causing the pin to rotate.