The torch is caused to make short and relatively rapid transverse oscillations of sweep across the width of a swath along the workpiece, the swath developing in {TAIL ~ the course} of {HEAD ~ a relatively slow feed} of the torch with respect to the workpiece 
The torch is caused to make short and relatively rapid transverse oscillations of sweep across the width of a swath along the workpiece , the swath developing in { TAIL ~ the course } of { HEAD ~ a relatively slow feed } of the torch with respect to the workpiece
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 TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH