blender library 3d models

I used GIMP instead of Paint.net for drawing the topography; Octave instead of MATLAB for plotting the 3D model; MeshLab for simplifying the meshes, instead of Microsoft 3D Builder; Freecad2 instead of SolidWorks for the tunnel and the World Engine;...

I used Blender to smooth the borders of the disc. The part you see in the original image is the "south" side of disc. That's because of its spin direction and the right hand rule, the south direction of the rotational axis is pointing almost directly...