1. A computer-performed method for distributing part mass data onto a finite element model, said method comprising the steps of: in a graphic display, displaying target property values pre-established for a plurality of properties of a part; selecting nodes from the finite element model to represent the part, the selecting performed using a selector method selected by a user; distributing among at least some of the selected nodes a pre-established mass value and only the pre-established mass value, the distributing performed using a distributor method selected by the user; determining values for a plurality of aggregate properties of the selected nodes resulting from the mass value distribution; modifying the mass value distribution among the selected nodes to obtain a modified mass value distribution that results in the aggregate properties of the selected nodes having values closer than the corresponding determined values to corresponding ones of the pre-established target property values for the part, the modifying performed using a solver method selected by the user; the method performed at least in part by at least one computer having a processor and memory.