118 directs molten metal towards second portion 102 b any surface that functions to direct molten metal towards second portion 102 b can be used but it is preferred that surface 118 is substantially planar and formed at a 30 u00b0 60 u00b0 and most preferably a 45 u00b0 angle portion 102 b which is preferably vertical but can be angled or curved extends from the bottom of section 102 a to the top of base or bottom 120 portion 102 b has a leading face or second surface 122 leading face 122 is preferably planar and vertical although it can be of any configuration that directs molten metal outward such as towards the wall of a pump chamber or other structure in which the rotor 100 is housed a recess 130 is formed in top portion 104 and preferably extends from top surface 106 to at least as far as the trailing face 132 of second portion 102 b as shown recess 130 begins at a position on surface 106 slightly forward of face 132 and terminates at a position even with trailing face 132 the purpose of recess 130 is to reduce the area of top surface 106 thereby creating a larger opening for more molten metal to enter into.