Create a drawing that is enhanced with an LED! This is a fun exercise in design and planning as you can base your design around the LED placement. For this example I’ve drawn a unicorn squid. I knew that I wanted to make a creature with a light-up eye, so I decided to combine a squid and a unicorn. After drawing the creature, I determined where the eye should go and then based the circuit path around that placement.
How to Make a Paper Circuit
Step 1: Test the LED and Battery
Locate your 5mm LED and coin cell battery. Wedge the battery between the LED legs with the positive side of the battery (smooth side) touching the positive (longer) leg of the LED. The positive leg of the LED will touch the positive side of the battery, and the negative leg will touch the negative side of the battery (textured side).
Step 2: Draw Your Design
Once you confirm that the battery and LED work, start drawing your design on the paper. Think about how you want to place the LED — part of the fun is thinking about how it fits into your drawing!
Step 3: Mark a Hole for the LED
After drawing your design mark where you want the LED to be placed. In this example, there is a small circle to show where the LED will come through.
Step 4: Poke the LED Through the Paper
After you decide where the LED goes, poke the legs through the paper. Be careful that you don’t make the hole too big. The LED bulb should remain on the top of the paper and not fall through!
Step 5: Mark the Positive and Negative LED Legs
Carefully flip over your drawing and separate the positive and negative LED legs. In the example, the legs are folded in opposite directions. Once the legs are folded out, mark the positive and negative LED legs. Remember, the positive leg is the longer one. If you’re unsure, use the coin cell battery to test again.
Step 6: (Optional) Trim the Excess Paper
Depending on the size and position of your drawing you may want to trim some extra paper. The battery is going to be ideally positioned on a corner of the paper, so if your drawing is far away from the edge you may want to cut some of the paper.
Step 7: Begin Drawing the Circuit Path
Using a pencil draw out lines from the legs of the LED. This will be the path that the copper tape follows. It connects the LED legs to the battery. Make sure that you keep a gap between the LED legs so that they don’t touch!
Step 8: Continue Drawing the Circuit Path
Continue to draw the circuit path, making sure that you’re extending outward from the LED legs. The paths should head toward a corner of the paper, where the battery will be placed.
Step 9: Outline the Battery
Once you’ve drawn the circuit path from the LEDs, place the battery on the paper near the corner of the paper. You want to place the negative side down. Leave enough room so that the corner can fold on top of the battery. In the example the paper is folded so that the fold is right on the outside edge of the battery.
Step 10: Fold the Corner Onto the Battery
Once the battery is drawn, fold the corner down. You may need to adjust the battery position at this point.
Step 11: Trace the Positive Side of the Battery
Once you’ve confirmed the battery position, trace a spot for the positive side of the battery. It’s a good idea to mark this side with a + symbol so that you remember the battery’s orientation. Notice that the circuit lines extend into the battery outline. This is to ensure that the battery connects to the copper tape.
Step 12: Measure and Cut the Copper Tape
Note: Do this for one path at a time. In this step, the copper tape is measured and cut for the path extending from the negative leg of the LED.
Try to measure the length required for one side of your circuit path and cut that amount of tape. It’s better to have a longer length than you need as it’s tricky to extend the tape if it’s too short.
Step 13: Add the Copper Tape
Start adding the copper tape to the path. Notice that the tape begins in the middle of the battery outline with the shiny side up. Press the tape down as you go so that it sticks to the paper. The shiny side of the copper tape is conductive, so you need to fold it over itself at the corner so that the shiny sides touch.
When you get to a corner, fold the tape away from the direction you want to turn, forming a sharp angle. Press down the tape onto itself, and then fold it back in the direction of your circuit path.
Step 14: Secure the LED Leg
Make sure that the LED leg lays on top of the shiny side of the copper tape. Once you have it in place, use a small strip of the copper tape to hold it in place. Try to secure it enough so that it won’t move away from the shiny side of the tape on the circuit path.
Step 15: Apply Copper Tape to the Remaining Circuit Path
Repeat the process for the circuit path extending from the other LED leg. In this example, it’s the positive side. Measure how much tape you need and cut a strip, estimating a bit longer than you may need.
Lay down the copper tape in the same way as the previous steps, and extend it along the path until it touches the positive side of the battery.
After finishing this step you’ll have placed copper tape completely along the circuit path, connecting the LED legs to the battery.
Step 16: Check Your Path
Double check that your tape extends into the circle you’ve drawn for the battery. In this example, the tape goes about halfway into where the battery will be placed.
Step 17: Place the Battery and Fold the Corner
Place the battery into the outlined spot, with the positive side facing up. Fold the corner down so that the copper tape touches the top of the battery. At this point your LED should turn on! If not, you may need to adjust the position of the copper tape or the battery.
Step 18: (Optional) Apply Binder Clip
This step is one of the two optional methods for securing the battery. Once the corner is folded, use the binder clip to hold the connection in place. If you do this, the LED will remain lit for as long as the clip holds it in place (and as long as the battery lasts).
Step 19: (Optional) Tape the Corner
If you aren’t using a binder clip, you can tape the corner instead. Fold the corner and wrap a strip of masking tape around the corner while applying pressure. Flip the paper over and reinforce the tape by adding more strips. Try to secure it without touching the copper tape.
If you choose this method you can experiment with how tightly you tape the corner. If you keep it looser you can then treat the corner as a pushbutton where the LED lights up when someone applies pressure!
Step 20: Admire Your Design!
You may need to make some adjustments to the battery and circuit, but at this point your paper circuit drawing is complete!