I love wearing things that light up. I’ve made and attempted to make a variety of light up jewelry and costumes over the last few years. Some (like my festive light up Christmas sweater have been successful) and others have just been frustrating. However, I have found some really awesome sewable LED lights and battery holders by Adafruit. They have made my wearable tech endeavors so much easier. So, easy in fact that I have successfully introduced similar activities to my middle school science classroom. This would be a fun 4th of July project and the bonus is that you will be able to locate your kids when the sun goes down and the fireworks come out.
Supplies Needed for DIY 4th of July Bracelet:
- 8.5” x 11” squares of felt in three colors
- hot glue gun
- conductive thread
- LED bulbs
- coin cell battery holder
- CR2032 coin cell battery
How to make your own 4th of July light up bracelet
- Start by downloading and printing the template from above. Then cut out all of your felt pieces.
- Place the battery and the LED lights on your main bracelet band. Be sure that the positive symbols for the LEDs are all pointing the same direction and that the battery is oriented so that the positive end of the battery is on the same side.
Gluing down the lights and battery holder
- Hot glue the battery holder and the LED lights into the locations shown. Note the lights should be glued face down in order for them to shine through the felt fabric.
- Glue the Velcro in place for the battery holder (see the right picture above). Don’t worry about the Velcro for the bracelet yet, as that will need to be sized for the wearer’s wrist.
- On the side opposite of the battery and lights hot glue on the stripes and star. If you place the star over the center light, it will light up when the circuit is turned on.
Sizing the bracelet
- You can also go ahead and size the bracelet at this point too. Wrap it around the wrist and allow it to overlap 1-2 inches and cut off any excess fabric.
- You can use hot glue to secure Velcro to both sides of the bracelet to create a secure connection. I added two sets of Velcro. I attached one fuzzy piece to the short edge of the inside (circuit side) and another fuzzy piece to the opposite short edge but on the outside (pretty side).
- Then I placed the matching “hook” side on top of the fuzzy sides, wrapped it around my wrist overlapping the ends and marked where the “hook” side should be and then hot glued them down.
Sewing the circuit for you light up 4th of July bracelet
A few words about circuits and LEDs: LEDs are directional lights, which means they won’t work if you don’t attach the negative side of the battery to the negative end of the bulb. In addition, you need to make sure you don’t create a short circuit. A short circuit is created by crossing your negative and positive “wires” (in this case conductive thread).
- Cut a piece of conductive thread that is twice as long as the distance between your battery and your last LED bulb (If you are a novice sewer, give yourself extra). Thread one end of the thread through your sewing needle. Do not tie a knot in the other end.
- Take the thread and loop it 4-5 times through the positive hole in the battery and then tie it off.
- Sew towards the positive side of the first LED light. As you sew do not go all the way through the felt. Just barely catch the fabric to keep the conductive thread all on the same side.
- Loop the thread through the positive side of the first LED light 3-4 times. Then sew in the same manner to the second light, loop the thread, and then go to the third (always going through the positive side).
- After you have reached the third LED, loop and then tie off thread. Your positive side is now complete.
- Cut a new length of conductive thread and complete steps 1-5 for the negative side.
- When you are done, you can add a dab of clear nail polish to all of the knots to keep them from coming undone.
- Now, slip the battery into the holder (you should be able to see the positive side of the battery when you are looking at the battery holder).
- Flip the switch on and your bracelet is ready to go!
Trouble Shooting your circuit
So, I made several of these and despite the logically correct circuit, I had some trouble shooting I still needed to do. One thing I discovered it that my Amazon purchases were knock-offs and not all of the battery holders worked. I recommend you order straight from Adafruit.com as it will save you some time. You can also order the LED lights from there, but my Amazon purchased ones seemed to work find. Here are some common mistakes that can cause your circuit to not work:
- Not wrapping the conductive thread through the hole enough times or wrapping too loosely.
- Having a long tail on your knot that crosses over the oppositely charged side of your circuit.
- orienting the lights or the battery the wrong way.
- If you want to get more tips or learn to sew more complex projects, you should definitely check out this website.