Introduction: CNC NeoPixel Jewelry
This is a prototype for a secure enclosure and substrate for creating jewelry with Adafruit's NeoPixels and Gemma microcontroller. The design is intended to provide an adaptable platform for diffusing, directing and modifying the light and colors emitted from the addressable LED NeoPixels.
It is my first CNC project and was completed during a short "Intro To Machining" class at the local community college. Big props to the instructor for going along with a project that far exceeded the class syllabus. This iteration was limited by available milling bits, materials, single face pass and class time.
In fact, the project is so rough and full of errors that no files are provided. I will probably take an actual CNC class next year and may revisit the design at that point. I am also eager to try the design on a 3D printer. If an improved design emerges, then there might be a reason to publish files for others to use. Until then, have fun and play with shapes.
Step 1: Materials and Design
1x - Adafruit 12 LED NeoPixel Ring
1x - Adafruit Gemma Microcontroller (now in V2)
1x - Small LiPo battery
3x - 1" long coated wires
1x - 6"x6"x1/2" PVC slab
1x - Soldering iron and solder
...plus fasteners to connect the pieces, paint, finishes and assorted bling to complete the jewelry.
- The NeoPixel ring, Gemma microcontroller and LiPo battery were measured with a caliper. The enclosure was designed to protect the electronics, leave room for easy installation, and provide room to add decorative external features.
- Over the course of the project, several 3D design and CAM programs were used as a way to explore real-world workflow. SketchUp, AutoCadLT, Inventor and MasterCAM were all used at some point.
- The radiating channels (part shown at left in drawings) are intended to modify the light from the NeoPixel ring. The LEDs are so bright that they can overwhelm viewers and can "mush together" into a single light field. The channels work fairly well, but with dark materials, an interior coating of white or reflective paint can help extend the distance the light travels. The differing lengths of the channels provided valuable info on how far the light can be "piped" before becoming unusable. Note that the milled piece features a hole not shown in these drawing.
- The "ring holder" part (middle in drawing) fit the NeoPixel ring snugly so that the channels aligned well with each pixel on the ring. Combined with the power, ground and data wires (routed through holes not shown in these drawings), the LED ring was quite secure and alignment remained dependable after a full day of wearing the jewelry. The center post also prevents "blowback" from the LEDS and keeps each pixel separate visually.
- The electronics tray (part at right in drawings) provides room for the Gemma microcontroller and a small LiPo battery. Sensors and switches have also been tested in the same space in an effort to make the piece interactive.
- The milled PVC parts are rather plain. Until the shapes are refined and transferred to wood or metal, the entire assembly requires paints and bling to indicate its life as jewelry, not an industrial sensor. But the project has given several local makers a chance to collaborate on electronics, coding, CNC, finishing and general design. That's a pretty good outcome for first try, though.