NeoPixel rings, and NeoPixels in general, are among the most popular electronic components for makers of all types. For good reason too, with a single pin from any popular microcontroller Adafruit makes adding gorgeous LEDs and animations to any project extremely easy.
Unfortunately they are rather expensive, and Adafruit only sells four sizes. What many makers don’t realize is NeoPixel is simply Adafruit’s branding of a few identical LED chips named WS2812, WS2811 and SK6812 respectively. All Adafruit does it take the chip and put it on a circuit board, charging a hefty premium alongside. There is nothing wrong with Adafruit doing this as it makes NeoPixels accessible to everyone, but if one were to simply make the boards themselves one could make custom shapes of any size or design for around 15% of the cost of Adafruit’s models (for a 24 LED ring)($3). More importantly, they cant be any size you need! Despite that, it doesn’t seem like anyone has created a guide exactly for doing this.
So, when I needed a custom compound ring for my working Samus Arm Cannon project (coming soon) I figured why not document the process.
In this tutorial I’ll show you exactly how I made this custom ring, and how you can make your own.”

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