PL9823 blade

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PL9823 blade

DIY Teensy based lightsaber

What you'll need:

~100 PL9823 or APA106 LEDs (make sure you get some extra, just in case)
tinned solid 20-guage wire for power rails (I used 18-guage, which is overkill)
7/8" diffused blade tube and end cap
3/4" diffuser
packing foam sheets - for diffusion
A 2.6k resistor - for blade identification
A 50-100Ohm resistor - to prevent the blade from leaching power over the data connection
female aviation connector
Aviation connector holder - Or get it from Shapeways. Make sure you get the right one for your blade tube. (Depends on inner diameter.)
packing tape and double-stick tape
22-26-guage wire
assorted shrink-tube

Putting it together The circuit is pretty simple. The green PCBs represents the PL9823 (or any WS2811 compatible LED), the connector on the left is the 8-pin aviation connector. In my configuration, pin 1 in the aviation connector is the bottom pin in the circuit diagram. You can do something different if you like, as long as it's the same in the hilt and in the blades.

Here is how I built the LED string.

Note how each LED is rotate 180 degrees from the previous one? That is so that the data out can connect to the data in on the next LED. During construction, I keep the "-" power rail on top at all times. I bend first and last pin straight out, then I position it so data out will connect with data in on the next LED, then I bend + and - to connect to the right rail. Then I wrap the power pins around the power rails, and finally I bend the data pins to connect together. The remaining pin will still be sticking straight out, and it will tell me how to position the next LED.

Then we need to attach the string to the connector, the following picture shows how the blade identification resistor fits snugly in the connector itself.

If you're using the same kind of connector I am, I recommend adding some hot-glue on the back of the connector to hold all the pins into place. They have tendency to come loose after a while and can cause shorts, leading to amusing but foul-smelling smoke to come out of your saber.

Once the string is all wired up, all you need to is to wrap it in packing foam and insert it into the blade. Instead of me explaining it (poorly), please watch this excellent video. Once it's done, it should look something like this:

And here is a closeup of the end, the plastic pieces should be glued to the blade, but make sure you use a glue that is safe for polycarbonate. I have in fact not glued these pieces in at all, as they fit quite snugly and are held in place with friction.

My blade ended up with 97 PL9823 LEDs. Each LED can draw about 60mA when white, so that means the whole thing can draw nearly 6A, also, it seems to draw a bit more than that during brief flashes or right when you turn it on, so make sure you have a battery that can provide enough current.

Problems? Questions? Suggestions? Check out The Crucible.

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Last modified: March 29th, 2021 - Design by Monica & Fredrik Hübinette