How to Build an LED-Lit Infinity Mirror Icosahedron

A regular icosahedron is a 20-sided polygon, which most of you are familiar with for its role as everyone’s favorite dice: the D20. Obviously, its a polygon that is important to many gamers and nerds — so much so that it’s a symbol of nerddom itself. So, why not celebrate that iconic shape by following Janth’s tutorial to build your own LED-lit infinity mirror icosahedron?

As you can see, the finished infinity icosahedron is dazzling to gaze upon. The inner side of each edge is lined with a strip of WS2812B individually-addressable “NeoPixel” RGB LEDs. Each of the 20 faces of the polygon is made from one-way acrylic mirror. So, the light from the LEDs bounces around inside the icosahedron off of the mirrored surfaces, but you can still see through those surfaces to get a view of the kaleidoscope-like display.

To create your own, you’ll need access to both a 3D printer and a laser cutter. You’ll use the 3D printer to make the edge mounts that hold the faces together and to which the LED strips are attached. The laser cutter is used to cut out the acrylic faces. The LEDs are controlled by an ESP32, so you can program them to show whatever patterns you like. Soldering the 30 LED strips into a single unit will be delicate work, but shouldn’t be too difficult if you’re careful. Then, just snap covers over each of the vertices, and you’re done! Janth has also provided a cube version, if you prefer Monopoly over Dungeons & Dragons.