Show HN: I made alchemical-cosmological PCB badges

Design

These are alchemical-cosmological PCB hackathon badges I designed in a day for the Fallout hackathon in Shenzhen, China. It’s 3 PCBs stacked on top of each other using testpoints, powered by the 10-cent CH32V003 MCU, with WS2812B neopixels.

There are 2 different PCBs: the outer ring and the inner sun. The 2 outer rings are soldered onto the testpoints of the inner one, with the second outer ring rotated 180 degrees to look more 3D. The rings have exposed soldermask so that the neopixels can shine through, and you actually only need to solder neopixels onto one ring to get the effect.

Power and Assembly

There’s also a battery connector on the top-left corner to attach a small battery with a voltage between 2.7V - 5V, and I’d just suggest a small LiPo, which can potentially even slot in between the boards. I’d also suggest putting a hole for your lanyard, because currently I just have a string wrapped around the board which looks cool, but isn’t the most convenient for assembly.

Cost and Manufacturing

Each full badge costs about $10 at MOQ, but I’m sure you could get that down to under $3 if you create quite a few at once. If you want to manufacture the boards, all of their production and development files are in their relative folder. I’d suggest getting the boards from JLCPCB with ENIG and a stencil for the inner board, and then buying the components from LCSC and hand soldering.

All the design files are open-source if you want to make modifications so that they’re unique to you, so just go crazy!! These boards were designed really fast and made to be really cheap because of a limited budget, so produce them at your own discretion.

Programming

These boards use the CH32V003 and program over SWIO using the header pins in the middle of the board. You’ll want to program the boards using either a WCH-LinkE or PicoRVD, which is what I used and what you’ll find in the firmware folder.