This particular attitude of small roller 50 assists in tending to lift and maintain the side edge portion 21a in the bight of the U shaped guide bar 48, keeping {HEAD ~ the sheet material} from migrating downwardly and out of {TAIL ~ the guide bar} 
This particular attitude of small roller 50 assists in tending to lift and maintain the side edge portion 21a in the bight of the U shaped guide bar 48 , keeping { HEAD ~ the sheet material } from migrating downwardly and out of { TAIL ~ the guide bar }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL