the purpose of illustrating the invention and it is understood that the scope of the invention is not to be limited thereby a 5 u2033 long spinnerette was used of the type shown in fig1 the spinnerette had 12 rows of nozzles spaced 0 060 u2033 apart within each rows the nozzles were also spaced 0 060 u2033 apart resulting in a total number of nozzles of 1000 the inner nozzles 4 mounted in plate 5 had an outside diameter of 0 020 u2033 and an inside diameter of 0 010 u2033 the outside nozzles 6 mounted in plate 7 had an outside diameter of 0 035 u2033 and an inside diameter of 0 023 u2033 air cavity 10 had a height of 0 500 u2033 air cover plate 15 a thickness of 0 063 u2033 air holes 17 shown in fig1 and 2 a had a diameter of 0 020 u2033 air cavity 19 had a height of 0 100 u2033 and air cover plate 20 a thickness of 0 063 u2033 the air holes 21 in plate 20 had a diameter of 0 048 u2033 the resin inlets 2 and 8 were each connected to a 1 u2033 24 1 length diameter ratio extruder subsequently referred to as extruder a and b respectively each capable of extruding approximately 10 lb hr of polymer resin extruder b sheath polymer was charged with high density polyethylene of melt index 105 dow chemical company 39.