In the arrangement of FIG 8 it may be desirable to provide increased relief behind each primary cutter 21 to reduce {HEAD ~ the area} of {TAIL ~ wear} flat which develops behind the cutting edge as the cutter wears down 
of
In the arrangement of FIG 8 it may be desirable to provide increased relief behind each primary cutter 21 to reduce { HEAD ~ the area } of { TAIL ~ wear } flat which develops behind the cutting edge as the cutter wears down
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH