We'll need to measure and cut some pieces of wire to form the necklace. I used four different colored 30AWG wires to tell the connections apart. Each wire will be slightly a different length. Depending on your size preference, you'll need to come up with your lengths. Here's a list of the wires lengths I used in my build.
- 33cm GND (blue) JST connector & power
- 30cm GND NeoPixel Jewel to GEMMA M0 (black)
- 31cm Data in NeoPixel Jewel to GEMMA M0
A self adjusting wire stripper can speed things up. This thing can eat through a few wires at a time, which is a lot faster than having to strip each one! We'll want to remove only a bit of insulation from each wire. Getting ready to tin these up.
Adding a bit of solder to the exposed wire will fuse all those strands of wire making it easy for them to stick. A pair of third helping hands can hold up the wires and keep them steady while soldering. Be sure to clean and tin the tip of the soldering iron before use!
Wiring NeoPixel Jewel
The wires are soldered from the back of the PCB. First, I tinned the four pins with a bit of solder. The colors follow common wire connections, red for power, black and blue for ground and green for data. I used a panavise jr. to grip the PCB and hold it steady while I soldered them in.
With the wires attached to the NeoPixel jewel, you can start adding beads to the wires, making two sets. One lace contains power and ground, while the other is data and the second ground. I meticulously threaded each bead through these wires. Consider the order and placement of the beads for a desired pattern. This is an optional step, so feel free to improvise and use your own materials. Perhaps some fabric sheathing or leather wrapping would work here?
Power and Ground
The voltage and ground wires are wired to the male JST connector. You can follow the same polarity as shown in the photo. The wires on the connector are a single color, but one of the wires has a gray marking on the insulation. You can use that as an indicator to tell the connections apart. Don't forget to add pieces of heat shrink tubing to insulate the exposed the connections.
Thread Beads (Continued)
Proceed to add beads to the second set of wires, the Data In and second ground. I follow the same pattern as the first set for consistency but you can make it asymmetrical if you'd like. The beads can slip out of the wires here, so be sure to temporarily tie them off. Next up, we'll hook up the wires to the Adafruit GEMMA M0.