What are we going to do with the pi? I like to make stuff with led’s, and have some ws2812 I got cheaply from ebay.
Leds are lightweight, and making a ball from paper/cardboard can work well for diffusion and separating the individual led’s.

I’m making 19 modules with a triangular shape to each contain one rgb led, then pack them all together to form an icosahedron. An icosahedron has 20 sides, but we only need 19 since we’re going to either put a stand in the place of one or put it on a table.

first sketch for a module:

First step: drawing up a template for a facet of the icosahedron. The easiest way for me was to use a 2d cad program, I used QCad, which is available for mac and linux and works pretty well. I did a couple of try’s to get to a size that I liked, and finally settled on an edge length of 3.5″. (print out on regular paper, cut out and glue, stick an led in it and see how it looks)

Once finalized, I print it out and cut pieces of cardboard.
Here’s the final cad drawing I used:
icosahedron

Use a needle to transfer the important points over to the cardboard.

Trace them and cut out.

Trace with edge of scissors on the fold lines.

Cut out the inner triangle for the window with a cutter. This will be covered with diffusing paper.

Fold and add some glue to hold it together. Add tape over the 3 edges to finish this module. Repeat 19 times.

I assemble the icosahedron in two parts, this makes it easier to wire up the leds later. Once everything is wired up and tested the two halves can be glued together.

Next step is to make 19 triangles from cardboard to hold the led modules. Put the led’s on the triangles and hot-glue the triangles into the modules.
Once the wiring and the led’s are tested and working, finalize the icosahedron by putting the diffusing paper on the mpdules. Tape and glue the modules together.