{TAIL ~ An apparatus} for machining a workpiece to {HEAD ~ a predetermined contour} in accordance with a reference pattern comprises a cam mechanism which defines the reference pattern 
{ TAIL ~ An apparatus } for machining a workpiece to { HEAD ~ a predetermined contour } in accordance with a reference pattern comprises a cam mechanism which defines the reference pattern
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH