Halloween LED Firefly Costume

About: I am Andy Rawson and I make things. I usually end up making things that are expensive to otherwise obtain. Like a Stereolithography 3D Printer or a Thermal Imaging camera. Check out my other projects at http...

Last year we asked our sons what they wanted to be for Halloween and they both wanted to be fireflies so of course that was what they were going to be. It went without saying that they had to light up so my wife started working on the costume and I worked on the lights. Of course there wasn't much time until Halloween so it had to be pretty quick and easy.

Step 1: Light

For each costume I started with a cheap high powered LED flashlight and took out the LED assembly.

Step 2: Batteries

Then I took 2 AA batteries and put a piece of jumper wire at one end with some foam tape to hold it in place. On the the other end is the wire that goes to the battery connector and to the LED assembly. I soldered the wire to the LED assembly leads.

Step 3: Switch

To make them able to light the lights when they wanted to I soldered a tiny switch and put heat shrink on it. I used the battery connector so the switch could be ran inside the sleeve of the costume and be removed from the light and the rest of the costume without having to pull the wire and switch out.

Step 4: Firefly

Here it is assembled. I don't have pictures of the rest of the costume parts but for the firefly light I cut out a sort of oblong half circle shape (see the drawing below) from thick styrofoam and cut a hole in the middle for the light. The hole I cut was just right and didn't need glue to hold it but I think hot glue would work fine. The battery pack was stuck to the styrofoam with 2 sided foam tape. My wife sewed a bag from yellow fabric and to make it keep it's shape she put fabric interfacing on the inside.

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    8 Discussions


    The rest of the costume is black sweatpants, a long sleeve black shirt and a wool hat with wire wrapped with sparkly ribbon for antennae. The shirt has 2 extra cotton stuffed sleeves with gloves sewn on for the extra legs. The red part is just a short vest shape with wings sewn on to it. The wings are a black mesh material cut into a wing shape then a thin wire is run around the edge and held in place with hot glue or tape. Then a wide ribbon or strip of cloth is sewn around the edge covering the wire (you could probably use iron-on adhesive tape). The bag with the light in it is attached to the inside for the shirt with some stick on Velcro so that it could come off when they needed to sit down. Hopefully that will get you started, let me know if you have any more questions and we would love to see it when you are done.


    I put a picture of the shape in the last step of the instructable. The styrofoam I had was about 1 1/2" thick but whatever you can find should be fine.


    8 years ago on Step 4

    I want to make one for my granddaughter, she is 19 months, i think this would be CUTE for her. She would love to play with the switch.


    8 years ago on Introduction

    That's really cute. Also a great safety feature for going out on Halloween night.