To Add a Mass (FEM mode)
2. Specify a descriptive name for your mass, or accept the default name.
3. Select one of the following from the Type list:
◦ Simple
◦ Advanced
◦ Component At Point (Available only for assemblies)
◦ Component Distributed (Available only for assemblies)
4. If you did not select valid geometric entities as references before you clicked > 
Mass, select them now. The selected references appear in the References collector of the Mass Definition dialog box.
Mass, select them now. The selected references appear in the References collector of the Mass Definition dialog box.5. In the Properties area, specify the mass properties that are relevant to your selection in the Type area.
6. Select OK to complete your definition, or Cancel to close the dialog box without creating the mass.
Return to Mass Definition Dialog Box (FEM mode).