Summary Fractal Bucky Balls (Truncated Icosahedron). Calculated by OpenSCAD - all the vertex coords are generated inside the program, using permutations of 3 simple equations with "golden ratio" ((sqrt(5) + 1) / 2). See OpenSCAD source. Print Settings Printer: Da Vinci 2.0 DuoRafts: YesSupports: Yes Notes: The "daughter" buckyballs are generated at the point so that a corner of daughter shares a corner of "mother" buckyball. The (mother:daughter) ratio is (1:0.175) which is the minimum ratio that the object be one solid (touched by the edge). I don't think recursive level >= 2 can be generated (limited by time/memory), nor printed out (resolution of printers). Somebody try. :-) The stl files are rotated to make the flat (hexagon) face bottom, resized to radius 50mm (level 0)/100mm (level 1), using Blender. See the comments in the OpenSCAD source about size specs, rotation angle. Fixed data using Microsoft Model Repair service. The pent.stl file and hex.stl files are for dual color filament 3D printers; I used Da Vinci 2.0 Duo, with white and black color. I hate dual color print because of the color contamination, but it's impossible to paint afterwards on level 1 pentagons in black. :-) The 100mm level 1 fractal solid is rather firm, could remove the supports inside using steep file. The upper side was beautiful, but the lower side (on supports) was a bit dirty... How I Designed This In the OpenSCAD program, the generation equations are beautiful, however, recursive part is dirty; many duplicated codes are there. This is because the OpenSCAD allows child recursive call (from March 2015 version), but don't allow child's child recursive call. I'll rewrite if OpenSCAD is improved, or find another way.