Plasticating apparatus screw having grooves of varying angles and depths

A screw for a plasticating apparatus, the screw comprising:

• a longitudinal axis, the screw being rotatably supportable in a barrel for rotation about the longitudinal axis, the screw having a core and at least one helical flight extending along a length of the screw, the helical flight extending in a first thread direction and defining a first helical path of a first helix angle measured relative to a reference line perpendicular to the longitudinal axis, the first helix angle being less than ninety degrees, the helical flight defining a helical channel;
• and
• a longitudinal portion of the screw having a plurality of advancing grooves being arranged in a noncontinuous helix cut in the screw core in the helical channel of the screw, each of the polarity of advancing grooves forming a second helical path in the helical channel and being arranged entirely between adjacent helical flights and extending substantially parallel to the helical flights and extending a length between a first end and a second end, wherein at least one of the first end and the second end comprises a closed wall configured to block flow out of the advancing grooves in a direction along a second helical pat, into the crosscut groove and the plurality of advancing grooves being dimensioned to receive material therein as the material is conveyed forward through the helical channel;
• the longitudinal portion further having a plurality of noncontinuous cross-cut grooves traversing at least one advancing groove;
• and
• at least one of the cross-cut grooves being oriented in the first threaded direction common to that of the helical flight and having a second helix angle measured relative to the reference line perpendicular to the longitudinal axis, the second helix angle being greater than the first helix angle and less than ninety degrees.