This 3D-Printed NeoPixel Fantasy Sword Costume Prop Features Great LED Effects

Halloween is right around the corner and we’re now in the costume crunch zone. I have no idea what you’re planning on dressing as, but I bet your costume could be improved with a cool LED-lit fantasy sword. There isn’t much time left to order the supplies and components you’d need to construct such a sword, but fortunately there is one you might be able to build with a 3D printer and hardware you have on hand. AGBarber has a very detailed guide explaining how they went about making an awesome 3D-printed NeoPixel fantasy sword prop that features great LED effects.

This is a bit of a complex build and it does require quite a lot of 3D printing, but all of the electronic hardware components are the kind that many makers tend to already have crammed in a box somewhere. It’s lit by a strip of SK6812 individually-addressable RGB LEDs, which are very similar to the more common WS2812b LEDs. The SK6812 LEDs were chosen because they are smaller in size and packed more densely on the strip, which helps to create smooth lighting effects. That’s particular true with a project like this, where there isn’t much room for diffusion. If you use AGBarber’s code, there are a total of 25 different LED effects that you can switch between on the fly.

Those LEDs are controlled by an Arduino Pro Mini 5V board. Power comes from a single 18650 LiPo battery cell via a TP4056 LiPo charging board. Most of your time will be spent 3D-printing all of the plastic parts of the sword. You’ll need a couple of different filament types, most notably transparent PLA for the blade of the sword so that LEDs can shine through. Most of the other parts can (and probably should) be painted. To follow AGBarber’s tutorial exactly, you will need to order two custom PCBs. One is for the Arduino to connect through and one is for the push button used to switch effects. It’s unlikely that you will get those before Halloween unless you pay for expedited fabrication and shipping, but you may be able to use a stripboard instead. We highly recommend that you do so. Even if you’re planning on dressing in a raunchy hazmat suit, you can’t go wrong with a sweet sword.