Once the extrudate is sufficiently buckled, {HEAD ~ the second diversion rod} is thereafter returned to {TAIL ~ its original position} 
is returned to
Once the extrudate is sufficiently buckled , { HEAD ~ the second diversion rod } is thereafter returned to { TAIL ~ its original position }
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL