This is a very straightforward build -- all you need is a yardstick and some zip ties to attach the NeoPixel strip, board, battery, and potentiometer!
We'll customize the build a little bit to give it a nice fit and finish.
You can skip this step if you like, but it's nice to trim off some of the excess length of the yardstick to make the Light Paintstick a bit more compact and easier to swing around in midair.
No need to measure! Just use a hand saw or power saw (bandsaw, chop saw, miter saw, jig saw, or table saw) to cut the yardstick at the 28-1/2" mark.
To make the Light Paintstick more comfortable to hold, you can use some sandpaper to shape the handle section a bit and round off the edges.
You may want to mount the Light Paintstick onto a bicycle or scooter to create some large-scale light paintings -- you can add some holes near the base of the handle to accommodate this.
Mark and drill two 1/4" holes as shown.
It's helpful to drill over a sacrificial piece of wood to prevent splintery blow-out on the back-side of the hole as the drill bit breaks through.
In a well ventilated area, set down some newspaper and a couple of blocks for standoffs.
Spray the yardstick with even coats of spray paint.
Allow to dry for 1/2 hour, then flip the stick and paint the other side.
Two full coats should be sufficient.
Marvel at how professional and awesome your Light Paintstick is now looking!
Now that he stick is prepped, it's time to add the electronics!
The potentiometer will be used to control the playback speed of the bitmap image. Connect it to the three sockets of the sensor cable as shown. The green wire goes in the middle to send potentiometer wiper position data, while red and black go to the outer pins for voltage and ground.
Connect the other end of the cable to the JST sensor port on the HalloWing.
This port is marked "SENSE".
Plug the NeoPixel strip connector into the NeoPixel JST port on the HalloWing.
This port is marked "NEOPIX".
You'll power the HalloWing Light Paintstick with a 3.7V lithium polymer battery.
The HalloWing even has a charging circuit built in, so you can recharge the battery at any time by simply plugging in a micro USB cable!
Plug the battery into the port marked "LiPoly Battery Only!"
You can secure the potentiometer-to-cable connection with a bit of tape to prevent it from disconnecting.
Now we can connect the HalloWing and components to the stick.
Lay the NeoPixel strip on one side of the stick, with the LEDs facing up.
Use zip ties to secure the strip to the stick.
Trim off the excess zip tie ends with diagonal cutters or scissors.
Connect the potentiometer to the Light Paintstick with a zip tie as shown.
Secure the battery just below the potentiometer with a zip tie.
Use four thin zip ties to secure the board to the stick.
Feed one zip tie through the two mounting holes as shown.
Use a second zip tie connected on both ends to the first zip tie on the underside of the board to join them.
Pull them snug but not too tight (don't want to put too much pressure on the TFT display!).
Trim the excess ends.
Here's what the finished HalloWing Light Paintstick looks like!
You can create a Circuit Playground Express Light Paintstick instead if you like! For this, we'll use a 3x AAA battery box instead of a LiPoly, a NeoPixel strip with alligator clips, and we won't use a potentiometer, instead controlling playback speed with the CPX buttons.
Use double-stick foam tape to connect the CPX to the stick, and to connect the battery box to the back side of the stick, behind the CPX.