Geodesic Sphere (Printed connectors + straws)

thingiverse

Want to make something a bit BIGGER than your regular 3d prints? This geodesic sphere is super easy and fun to build! Just print 12 of the 5-way connectors and 30 of the 6-way connectors, then connect it all up using straws! No glue, screws, support, or any other materials are needed. The result is a beautiful, solid 2v geodesic sphere with 42 vertices and 80 triangles. There are 120 struts, which can be made from 60 straws for a small sphere or 120 straws for a big one. I recommend using paper straws, like these that I bought from Amazon: http://amzn.com/B07JR64BSK # Assembly Instructions - **Calculate your strut sizes and cut your straws**. - If your straws are 197mm like those linked above, then I recommend: - **Small sphere**: use 60 straws, each cut once to create 93mm short strut and a 104mm long strut - **Long sphere**: use 60 full length straws as your long struts, and 60 straws cut to 152mm as your short struts - If your straws are a different length, just make sure your struts obey the equation `(LONG - 12)/(SHORT - 12) = 927/820`. This is because the connectors add 6mm to each side of each strut. - **Print a test piece** to check straw fit. - Ideally it takes significant force to push the straw on so that it can hold some tension (after all, geodesics are a tensegrity structure!). If it's too tight though and you cant slide the straw all the way on, raise `PLUG_CLEARANCE` in the SCAD file to a less negative value (and vice versa if too loose). - **Print 12x 5-way connectors and 30x 6-way connectors**. No support is needed, but add a brim if you have problems with adhesion to the bed. - **Attach all the short straws** to the 5-way connectors - **Build the rest of the sphere** using this simple rule: "short straws connect to short straws". This means each short strut on each 5-way piece will have a 6-way connector on the end, with another short strut coming off the directly opposing (in-line) side of the connector. The other 4 plugs on the 6-way connector will each get a long-strut (you can think of the long-struts as forming the sides of the pentagons surrounding the 5-way connectors) I'm working on some very cool related Things that hopefully I'll be posting soon!