Punching die set

Claim 1

A PUNCHING DIE SET FOR USE ON A BASE AND TO BE ACTUATED BY A RAM COMPRISING A SUBSTANTIALLY FLAT MAGNESIUM PUNCH PLATE, A SUBSTANTIALLY FLAT MAGNESIUM DIE PLATE, MOUNTING MEANS FOR MOUNTING THE PUNCH PLATE AND DIE PLATE IN PARALLEL FOR MOVEMENT TOWARD AND AWAY FROM EACH OTHER THE MOUNTING MEANS INCLUDING INTERCHANGEABLE GUIDE PINS HAVING ANNULAR SLOTS AROUND THEIR PERIPHERY, PRELOADED SPRINGS MOUNTED TO TEND TO SEPRATE THE PUNCH AND DIE PLATES AND FIRST GUIDE PIN RETAINING RINGS PLACED IN THE GUIDE PIN ANNULAR SLOTS SO AS TO SECURE THE GUIDE PINS TO THE PUNCH PLATE AND SECOND GUIDE PIN RETAINING RINGS PLACED IN THE GUIDE PIN ANNULAR SLOTS SO AS TO ALLOW A PORTION OF THE GUIDE PIN TO MOVE THROUGH THE DIE PLATE DURING THE PUNCHING OPERATION BUT TO LIMIT THE RETURN TRAVEL OF THE PUNCH PLATE UNDER THE URGING OF THE PRELOADED SPRINGS, TO THE NORMAL OPEN POSITION OF THE DIE SET WHEREBY THE GUIDE PINS MAINTAIN ALIGNMENT BETWEEN THE PUNCH AND DIE PLATE WHEN THE DIE SET IS COMPRESSED BETWEEN THE RAM AND THE BASE.