Decorative Disks - Bucky Balls
by pmoews, published
Three dimensional molecules like fullerenes (Bucky Balls), see thing:12675, can be converted to 2 dimensional patterns by projection onto a plane. Projections are like shadow silhouettes. Atoms (spheres), become circles and bonds (cylinders), become rectangles. When symmetrical molecules are projected atoms shade one another and interesting patterns are formed.
I took the 15 fullerenes containing 20 to 80 carbon atoms and projected them onto three planes. The 10 most interesting patterns were used to decorate the disks described in thing:26973.
Three pairs of stl files are provided for two color printers:
disk_less_c24_down_z.stl and c24_down_z.stl
disk_less_c36_down_z.stl and c36_down_z.stl
disk_less_c60_down_y.stl and c60_down_y.stl
All 10 patterns are contained in disk_bucky_stl.zip and bucky_disks.scad is the program that created the files.
The patterns depend on the orientation of the coordinates in the fullerene data bank. Only three of the infinite number of possible projections for each molecule were calculated. Most of the interesting patterns came from projections down the z axis.
Two patterns are shown twice in the image at the upper left; the two colors used are switched. The patterns at opposite corners are from the fullerene containing 24 carbon atoms and all 24 atoms are displayed in two concentric rings. The two ajacent patterns are for the basic 60 atom Buckyball. Only 32 of the 60 atoms appear, the rest are shadowed. The projection of the fullerene containing 36 carbon atoms shows 18 visible atoms in the form of a hexagon surrounded by 6 pentagons.
All the disks were printed on a Replicator. I used zero shells and 50 percent infill and allowed the disks to cool for a few minutes before removing them from the build platform.
Input for the decorative modules is the same as that used in thing 12675 and the modules in bucky_disks.scad were simplifed from the openSCAD program in thing 12675. They now calculate two dimensional projections instead of three dimensional molecules.
Some information about using the program is included in thing 26973.