The blade of the lightsaber will light up from within using a strip of NeoPixels. To get things looking their best, we want a nice stable blade with good diffusion so you don't see the individual LEDs.
For this, we'll use two strips of corrugated plastic (A.K.A., CoroPlast) to sandwich the LED strip. The sandwich will then be inserted into the plastic tube with a roll of parchment paper as a diffuser.
First, remove the plastic end caps and cut down your plastic tube to 24" in length. You can use a hobby knife or scissors to to this.
Plastic and NeoPixel Sandwich
Measure and cut two strips of translucent corrugated plastic a little shorter than the NeoPixel strip, and just a but less than the inside diameter of your tube.
Make the sandwich, and then use strips of clear tape to secure it.
Measure and cut a length of parchment paper the same length or a few inches shorter than your tube. (Full length is fine, but a bit shorter makes cable management a bit easier later).
Carefully roll the paper, avoiding wrinkling it, to just a bit smaller diameter than the tube, then insert it into the tube.
Insert the Light Strip
Carefully insert the plastic/NeoPixel strip sandwich into the tube, being careful not to bend the diffusion paper.
Use scissors to cut a short slit in the tube end. This is used to allow the wire to exit the tube without eating up too much of its length!
First, we'll show how to re-use a toy lightsaber handle. If you want to use a plumbing sink extension instead, scroll down a bit.
Extend the blade and then use a hand saw or power saw to cut through the end of the bottom section. This will allow us to remove the other, smaller sections.
Now you can place the battery into the base of the tube blade and run the wiring out of the slit.
Place the tube guard over the remaining toy blade as shown.
Push the tube down into the handle.
Now we can connect the speaker, battery, and NeoPixel strip to the HalloWing, and then mount it to the lightsaber handle.
You can attach the HalloWing and speaker to the lightsaber handle as shown, using double stick foam tape. Zip ties work great as well!
For the sticker, you can peel off the adhesive oval's covering and connect the speaker directly to the handle. Even though the speaker is technically "facing in" it is of nearly the same volume either way -- this may be due to the handle acting as a resonator.
You can make a nice handle for you saber with all kinds of materials found at the hardware store. I picked a 1-1/2" x 12" sink drain extension tube. Here's how to incorporate it.
The diameters of the tube guard blade and the handle are not the same, so we'll create a tight coupling for them using corrugated plastic.
The key here is to transform the corrugated plastic, which is normally stiff, into a bendable sheet by slicing through the top face.
Cut a piece of corrugated plastic about 4" wide by 2-1/2" high making sure that the fluting is running vertically as shown.
Being careful not to cut through the bottom face, use a hobby knife to slice the top face between each flute of the corrugation.
You'll now be able to easily bend the plastic, wrapping it around the base of the tube.
Use a strip of tape to secure the coupling as shown, and then push the assembly into the handle, making sure to allow the wires from the NeoPixels and battery to clear.
Now, you can connect the HalloWing to the NeoPixel strip, battery, and speaker by plugging them into their respective JST ports.
How you dress up and style your handle is a matter of personal choice. Express yourself!
Here, I decided to go with a retro 80s sci-fi styling by adding an alternating black-and-chrome grip motif to the handle.
I did this by cutting and slicing another piece of corrugated plastic, attaching it with tape, and then using a chrome paint marker.