A third improvement comprises a sweepable member having a chamfered edge in a sweep direction, the edge making an angle of {HEAD ~ between about 5 8 degrees} with {TAIL ~ the plane} of the path 
with
A third improvement comprises a sweepable member having a chamfered edge in a sweep direction , the edge making an angle of { HEAD ~ between about 5 8 degrees } with { TAIL ~ the plane } of the path
OTH 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 HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH