Truncated icosahedron

thingiverse

A three-dimensional shape that looks like a soccer ball and can be made as big as a soccer ball. The design is fully parametric so can be printed at any size. If you want, you can replace one or more of the hexagons with other printed parts that have the hinges in the same position and create more things. Instructions You need twenty hexagons to print the ball, 10 type A and 10 type B. They differ in the type of hinges they have on three sides. Type A has two inner hinges and one outer and type B the opposite. Each STL file contains one A and one B. You'll also need filament to use as the hinge pin. I use glow-in-the-dark because it's about the right size, often needing to sand it down a little. I recommend printing one pair of parts and then making sure you are happy with the inner diameter of the hinge before going on. The models I built (0.2 mm layers in white PLA) stay together purely by friction, but for a permanent model you'll want to add the pins. The large ball was about 13 hours print time on a Replicator 1 and weighed about 200g. The small one took much less since I could get lots of parts on the plate at once. Once printed, lay the parts out in the way I show in the photos, paying careful attention to which hinge is which, then mate the parts. Finally roll up into a ball and add the pins. To build from SCAD, put all the files in the same folder, then open the hex.scad file. It may take a minute or two to open since it is slow to render. Edit the parameters at the bottom to change the dimensions. You will want to keep the hinge diameter the same as the thickness of the piece. The SCAD files allow you to vary the number of sides on the part too, but as written will take some extra coding to vary the number of hinges from three.