gCAD3D is a 3D CAD CAM application that features an integrated 3D OpenGL
viewer, a program interpreter for geometry and NC-commands in 3D, an
integrated NC-processor, and a programming interface for user programs.

It can
-Import and display data from Iges, Step, wire frame and solid objects
-Create and modify wire frame elements
-Create surfaces
-Create simple solid bodies
-Assemble user-created ancillary programs
-Export wire frame elements as DXF and Iges
-Export surfaces as Vrml-1, Vrml-2, obj, tw Iges

It cannot yet
-Blend or modify surfaces
-Create or modify complex solid bodies