Making the NeoPixel garment

Duration

The time required will vary greatly depending upon the scope of the project, the spacing of the NeoPixels, and the experience of the maker. The skirt in the example took about six hours to make.

Materials

• Flora NeoPixels
• Conductive 2 or 3-ply thread
• Normal sewing thread
• Small needle
• Scissors
• Skirt or other garment of choice. The skirt in the example has tulle on the outer layers, which is great for diffusing the NeoPixels’ light.
• Clear nail polish

Optional

• Fabric glue
• Fabric pen or tailor’s chalk

Plan it!

Sketch your proposed wiring on paper. Remember that none of the lines of conductive thread can touch each other. The GND pins can service multiple NeoPixels, as can the 3.3V and VOUT for power. The Flora NeoPixels have arrows on them, and these should point away from the Adafruit Circuit Playground Express. Connect 3.3V to the positive side of the NeoPixel on the right, a pin from A0 - A7 in the center, and GND to the negative on the left.

If you are planning a number of NeoPixels in a chain, the GND and 3.3V / VOUT lines should connect all the way from the originating power or GND pin to every positive or negative loop on the NeoPixels. If you have to start a new piece of conductive thread on the needle, try to make this transition at the eyelet of the NeoPixel so you can loop it through a number of times and get a good contact between old and new thread. The middle signal thread will stop and start on either side of the NeoPixel (see below).

Be sure the arrows on the NeoPixels point away from the Adafruit Circuit Playground Express.

Important: This view shows how the yellow signal thread that runs from a pin like A0, A1, etc. stops at one side of the NeoPixel and resumes on the other. This allows the signal to pass through the NeoPixel and give directions.

When you have drawn a plan that seems promising, test it with alligator clip wires. Make all the connections as you expect to make them with conductive thread, do your coding, and test. It’s much better to work out problems at this stage than after having invested time into sewing the lines incorrectly. Remember that the colors of alligator clip wires don’t matter in terms of functionality (they are all the same inside), but color coordinating helps keep you organized.

Sew on Adafruit Circuit Playground Express

Using traditional thread, secure the Adafruit Circuit Playground Express to your material. Use some of the pin tabs that you won’t need for the conductive thread. Be sure to align your Adafruit Circuit Playground Express so that the JST battery connection port is oriented toward where you plan to keep the battery. Also be sure to leave access to the micro USB port so that you can change your code if needed. This port can sometimes catch finer material like tulle, but a small piece of masking or packing tape solves the problem.

To knot thread off, you can run the needle through a stitch on the back side.

Run the needle back through the resulting loop, repeat this process several times, and you will knot off the line.

Stitch on the NeoPixels

Now that you have the Adafruit Circuit Playground Express securely fastened to the fabric, it’s time to use conductive thread to make the electrical connections. Using the wiring diagram you drew earlier as a guide, sew connections between the power (3.3V), ground (GND), and signal pin tabs. A simple running stitch works well. Take care that none of the lines of conductive thread touch each other. Also remember to end a line of stitching at the middle of a NeoPixel and resume with new thread on the other side.

You can use a single line of stitches that begin and end at eyelets on the hardware.

You can also use a double line of stitches. This is more work but makes a more reliable connection. If using this method, start sewing an inch or two away from the hardware, then sew to it, leaving a tail of thread hanging out of your first stitch.

Sew to one piece of hardware, then back to the other. At the eyelets, loop around the hole about three times, then run a stitch in through the loops, then go through the eyelet one more time. It’s vital that there’s solid connection at the eyelets.

Once you sew back to the starting place, you can use the tail you left sticking out to easily tie several knots. Add a dab of clear nail polish to help prevent it from unraveling.

The end result of either the single line of stitches or a double one should be lines of thread that make strong connections and that don’t touch.

Sew the power connections

Sewing a simple pocket can be a good way to tuck away your battery pack. Lithium polymer (LiPo) batteries are often great for wearable projects since they come in various compact sizes and are rechargeable.

Here you can see conductive thread running from the 3.3V pin to the positive eyelet on the NeoPixel, another line running from pin A4 to the center of the NeoPixel (arrows pointing away from the Adafruit Circuit Playground Express), and a line running from a GND pin to the negative eyelet on the NeoPixel.

The positive and negative lines of thread each, respectively, form a continuous chain, but the signal line in the middle needs to stop and start on either side of the NeoPixel.

For more on working with conductive thread and NeoPixels see a great video by Becky Stern of Adafruit:

https://learn.adafruit.com/flora-rgb-smart-pixels/add-more-pixels

Here’s another video resource: