in a closed clamping position ready for processing members 62 64 66 and 68 hold cams 70 and 76 and part blank 32 in a stationary position relative to each other jig carriage 46 fig1 a and 2 also includes overhead structure 92 for closingly clamping and also openingly unclamping blank carrying jig 48 overhead structure 92 is supported by upright posts 88 90 which are mounted to the front and rear of jig carriage 46 mounted to the sides of posts 88 90 are ramps 94 only one of which is shown which align with cams 70 and 76 and cooperate with cam followers to prevent posts 88 90 from striking and damaging heads 34 and 36a 36g overhead structure 92 includes multiple vertical posts 96 welded between two horizontal rails 100 and 102 which create a rigid framework five air cylinders 104 attach to the top of lower rail 102 between rails 100 and 102 and include downwardly extending shafts 106 which attach to brackets 108 located along the top of top clamping member 62 air cylinders 104 are generally uniformly spaced along rails 100 and 102 to provide a uniform lifting force and also alternatively apply a downward clamping.