FlexiBall is a modular PCB origami of icosiedodecahedron. It has twenty flexible PCB of triangular shape. Each PCB is identical and has four WS2812B-2020 LEDs in serial. Once these twenty triangular faces are connected with soldering iron. They forms twelve hollow pentagonal-faces. So FlexiBall is an icosiedodecahedron.
Each triangular PCB has four LEDs on one side and one FPC connector on the other side. One of PCB should have its FPC connector soldered. This connector serves as power and signal interface for an external LED controller.
Here are the details of soldering and assembling a FlexiBall.
2
Solder LEDs
There are four WS2812B-2020 LEDs on the front side. Make sure the orientation of each LED is correct. FPC connector should be on the another side of the PCB.
Tip: Flexible PCB is different from rigid FR4. The usual third-hand is not recommended because its teeth of clips makes dents on flexible PCB. Use one PCB holder or wise without too much force so that the flexible PCB is just held there without moving or bending.
3
Solder two flexible PCBs together
After the LEDs are soldered, it is natural to connect two PCBs together.
Each PCB has three connection port. There are one input with a label of "I" and two outputs with a label of "O". There is a small gap on each connection port. Put two PCB as the above before soldering.
There are two cases of soldering. One is just to solder two connection ports on the FPC side only like the below. These are only ground on the FPC side.
Another case is to solder solder the connection port on both LED side and FPC side. It is to connect both power and signal (on LED side) and ground (on FPC side). Below is one example.
This is super creative!