An injection molding system is disclosed that includes a mold insert set and a shaft locking assembly that releasably attaches the mold insert set to a mold plate of the injection molding system. Each mold insert of the mold insert set defines at least a portion of a mold cavity. The shaft locking assembly is displaceable between a locked position in which the mold insert set is held to the mold plate and an unlocked position in which the mold insert set is removable from the mold plate.