First attempt to create an object from scratch using Autodeks's 123D Design and 123D Make to do the slicing of the 3d model and turn it into an interlocking sliced object. Modeling in 123D Design took 30 seconds it is basically a shelled deformed sphere. After that the 3d model was imporrted into 123D Make, sliced and exported to dxf twice, with material settings set to 9mm to get the right sized slots in the small rings and one time at 2 mm to get the small slots in the 9mm thick large elipse. After export we added two cuts in the main large elipse and some small screw holes. Also the plates to sandwhich the cuts were dawn using the same screwhole layout. This was done in a separate cadtool.
8mm MDF (9 mm was out of stock but this caused no problems)
2mm grey cardboard