Mounting the ungainly WS2812 LED test fixture seemed like a Good Idea to keep the electricity out of the usual conductive litter:
The solid model shows more details:
The power wires along the array edges slide into the rear (thinner) slot, with enough friction from a few gentle bends to hold the whole mess in place.
The knockoff Arduino Nano rests on the recessed ledge in the pit, with M2 screws and washers at the corners holding it down (the PCB’s built-in holes might work with 1 mm or 0-90 screws, but that’s just crazy talk). I soldered the power wires directly to the coaxial jack pins under the PCB; they snake out to the LEDs through the little trench. There should be another cutout around the USB connector for in-situ programming, although the existing code works fine.
The front (wider) slot holds a piece of translucent white acrylic to diffuse the light:
It’s painfully bright: a few layers of neutral density filter would be appropriate for a desk toy.
The array runs hot enough at MaxPWM = 255 to produce a gentle upward breeze.
It looks even better without the flash:
You’ll find many easier ways to get RGB LED panels, but that’s not the point here; I’m waiting for these things to die an unnatural death.
The OpenSCAD source code as a GitHub Gist: