a front stop mechanism disposed downstream from the input section and mounted to the front stop support plate, wherein translation of the front stop support plate along a general direction of the material flow path varies {HEAD ~ a distance} between the front stop mechanism and {TAIL ~ the input section}; and 
between
a front stop mechanism disposed downstream from the input section and mounted to the front stop support plate , wherein translation of the front stop support plate along a general direction of the material flow path varies { HEAD ~ a distance } between the front stop mechanism and { TAIL ~ the input section } ; and
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 OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH