Improved method and apparatus for
interlocking hemmed together edges of inner and outer vehicle body panels with an improved
interlock joint. The inner panel blank is draw stamped and provided with PLP holes in a
stamping press. A plurality of conventional hardware components are then welded to the inner panel. Then
interlock holes are formed by a piercing tool moving through the inner panel border from its outboard to its inboard side while the inner panel is held by clamps and PLP pins. The hole piercing punch thus leaves cold worked upset material slightly raised inboard, rather than outboard, around the pierced
interlock hole margin. Then the inner panel subassembly is married to the outer panel and transferred to a hemming
station and again precisely clamped and positioned by PLP pins, whereupon hemming press gates are operable for hemming the
flange lip of the outer panel over the inner panel border. The final hemming steel of each gate carries
staking punches that individually strike a precision registered portion of such hemmed lip to deform it into locking engagement with the associated interlock hole. The upset material is thus flattened and accurately worked into
embedment into the interior surface of the hemmed
flange lip, rather than into the interior surface of the outer panel, thereby avoiding creating
read through problems on the outer panel.