A first drive unit moves the tool along {HEAD ~ at least two axes} to shape the workpiece similar to {TAIL ~ a desired surface} 
A first drive unit moves the tool along { HEAD ~ at least two axes } to shape the workpiece similar to { TAIL ~ a desired surface }
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL