A processing stage may be included which has {HEAD ~ a pair} of surfaces configured to heat and compress {TAIL ~ the tow} therebetween 
A processing stage may be included which has { HEAD ~ a pair } of surfaces configured to heat and compress { TAIL ~ the tow } therebetween
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH