Making a pencil bag from Duck Tape has been one of our favorite Farmer’s Market activities each year. What kid wouldn’t love a colorful, waterproof bag they made for themselves? But this year, as part of my local Maker Clubs at the library I wanted to take it up a notch, so we created bags that light up too!
First, we need to assemble some simple supplies:
- Duck Tape — any patterns or colors will work
- a one-gallon reclosable plastic zipper top storage bag — slider style bags will not work for this project
- 1/4″ copper tape with conductive adhesive
- 1 5mm LED — any color
- 1 3V coin cell battery, CR2032 or CR2025
- Stickers, sequins, rhinestones, etc.
The first step is to cut the bag down to size. I usually remove the bottom 1/2 to 2/3, leaving the zipper top. Try to make the cut straight, but it doesn’t need to be perfect. You won’t see it once the bag is covered. Then cover both sides of the bag with Duck Tape. Make sure that you seal the bottom with tapeand reinforce the sides.
Once your bag is covered, it is time to add the copper tape and create our circuit. The simplest design is a straight line the loops from front to back. So about 2 inches up from the bottom on the back of the bag, start your copper tape. Carefully apply it downwards towards the bottom of the bag and loop over to the front. End wherever you plan to place your LED. I like the middle of the bag. Press the tape down well.
Next, attach the battery to the back of the bag. Fold over a piece of copper tape to create a loop with the sticky side out. Place this on top of the end of the tape on the back of the bag. Place your battery on the tape, positive side down.
Next, adhere the copper tape to the top of the battery (the negative side) and run the tape towards the top of the bag (with the zipper). Carefully fold the tape over the back side of the top of the bag and into it. It should cross the zipper portion of the bag about half an inch. Press the tape down well.
Starting from the inside of the front of the bag, apply tape folding over onto the front. Make sure the copper tape from the front and the back of the bag line up well and can touch with good contact when the bag is closed. Continue the tape down towards your LED location. Stop the tape 1/4 to 1/2″ from the tape you looped over from the back.
Now it’s time to attach our LED. Start by identifying the positive lead. This is the long leg of the LED. The other, shorter leg is negative. It’s very important that the positive leg of the LED be attached to the part of the circuit that goes to the positive side of the battery. Using your fingers or a pair of needlenose pliers. turn the straight legs into loops. This will create a better contact for your LED to the copper tape. Place your LED onto the circuit so that the positive lead touches the tape running up from the bottom of the bag, and the negative lead touches the copper tape running down from the top.
Before you go any further, stop and test your circuit. Press the zipper top of the bag together and press the leads fo the LED onto the tape firmly. It should light up. If it doesn’t check that you have good contact at the zipper top (add additional copper tape if needed) and at the battery. Also, confirm that you haven’t accidentally connected the leads incorrectly.
Once the circuit works, use additional copper tape to attach the LED to the bag. Be careful not to cross the gap between the copper tape of your circuit. That will “short” your circuit, and the LED won’t light up. Then cover the battery on the back of the bag with Duck Tape.
At this point, I like to make an additional small rectangle of Duck Tape “fabric” (where you stick the Duck Tape to itself). I attach this inside the flap so that, if I want, I can block the circuit from being completed. That way I don’t waste my battery.
After that have fun and decorate your bag. Once you have a general idea, you can, of course, vary it up, making more complex circuits with the copper tape and even adding additional LEDs.
If you love free projects like these, please consider donating to my Summer of Science Go Fund Me Campaign! Every dollar goes towards bringing STEM activities to kids in the NWNJ area all summer long!