96 the swinging carrier 96 is formed with an open ended slot 100 straddling the support pin 84 co located on support pin 84 for pivotal motion is a swinging frame 102 having a first portion 104 extending therefrom for eventual connection to the rock shaft 48 of the feed mechanism a second portion 106 of the swinging frame 102 is formed with an open ended slot 108 therein straddling an enlarged slabbed section 97 of the support pin 98 on the swinging carrier 96 by referring to fig1 through 4 it can be seen that any swinging movement of the swinging carrier 96 will be transferred to the swinging frame 102 a sliding cam follower 110 is provided engaging on one side the rollers 94 and engaging on the other side thereof an edge cam 112 mounted on the feed shaft 32 the cam follower 110 is mounted to a holder 114 which is slideably mounted in the frame 85 a slot 115 is formed in the holder 114 allowing the feed shaft 32 to pass therethrough biasing means in the form of spring 116 and slide block 117 are provided for maintaining positive engagement of the cam follower 110 with cam 112 mounted adjacent to cam 112 on feed shaft 32 is a second cam 118 for influencing movement of a locking lever 120 which is also pivotally mounted on support pin 84 the locking lever l20 has an.