Something like freecad http://www.freecadweb.org/ sems has some volume dimensions
even curiously they have not 3dm format ! 3dm is not OpenNurbs?
STEP, IGES, OBJ, STL, DXF, SVG, STL, DAE, IFC or OFF, NASTRAN, VRML in addition to FreeCAD's native Fcstd file format.