No matter who you are – a STEM teacher, a makerspace maven, or just someone new to electronics – paper circuits are a wonderful way to begin understanding circuits.
In this post we’ll take a look at what paper circuits are, the paper circuit supplies you need to start exploring them, and some great guides to paper circuit projects.
Circuits? On Paper?
Let’s start by looking at what paper circuits are. As you know, electronic toys and gizmos use a power source like a battery or a power outlet; components that do work like lights, buzzers, motors or whatever; and wires that connect the power to the components that do something.
With paper circuits, instead of using wire you use copper tape along with batteries and LEDs or other components. Copper tape is – surprise – tape made of copper. Conductive copper tape comes in a roll that has a backing you peel off to reveal sticky stuff on one side. (Note that you can also use our conductive ink pens instead of copper tape.)
The thing I love about teaching electronics with paper circuits is that when you’re designing and then making a circuit on paper, you’re actually diagramming the circuit as you construct it. Your mind connects the dots about what is going on as you lay it down on paper. If it doesn’t work and you have to troubleshoot, you track down the problem in a visual way by following the diagram and puzzling out what’s going wrong where.
Once you get the basics down you can move to more advanced learning tools like using breadboards and wires, soldering, and Arduinos, sensors, and shields.
Some other great benefits of paper circuits are:
- They won’t shock you because there’s not enough current flowing through tape from the kinds of batteries you’ll use to give you a jolt
- You just need simple supplies like a coin cell battery, copper tape, and some LEDs; no need for soldering equipment, breadboards or other gear
A Brief Aside About Soldering
Just so you know, teaching kids to solder is a great thing to do. As long as they’re under adult supervision and follow safety precautions, even kids under 10 can solder. We’ll write about that in a later blog post.
To make paper circuits, the most basic supplies you need are as follows:
- Copper tape
- A battery (usually a coin cell battery)
- Clear tape
The simplest paper circuit experiment you can make is this one. I’m going over this here so you can get a clear idea of a good first circuit to make, but follow the links below to find a host of great projects that can even get quite complex.
To make this super-simple copper tape circuit, do the following.
Two notes first: Copper tape does not conduct electricity on the sticky side, so in order to turn corners, you have to bend the tape without cutting it. Or if you do cut it, you’ll have to figure out how to connect any two pieces so that the non-sticky sides touch each other. (If you have trouble, think of it as an opportunity to practice troubleshooting!)
Also, LEDs are diodes, which only allow the flow of electricity in a single direction. The longer wire leg of an LED has to be oriented to the + side of the battery or it won’t light up.
OK, let’s go:
- Trace your coin cell battery where you want it to go
- Start laying down a section of copper tape by removing the backing and sticking it to the paper. Start at the circle you traced and lay down tape basically in a half circle (it can be curved or straight lines)
- Cut or tear the tape, and then lay down another section of copper tape starting just outside your coin cell battery circle that leads almost to the other section of tape. The gap between them is where the LED will go
- Tape an LED down across the gap using clear tape, with one wire touching each bit of copper tape
- Crease the paper so that the bit of tape that doesn’t go into your traced coin cell circle bends over and will touch your battery from the top
- Plop the coin cell into the circle and try out your circuit by folding over the crease
Note that if LED doesn’t light up, chances are your + and – on the battery need to be reversed.
…Or Draw It
If you’re a fan of Circuit Scribe – and hey, you’re already visiting our site! – you can make the same circuit substituting our conductive silver ink for the copper tape. Here’s what that looks like:
Good Paper Circuit Recipes and Ideas
The circuit above is designed to show you the basic concept of paper circuits using picture. But know that you can take this basic technology and expand it greatly – you can even solder to copper tape!
So let’s look at some great resources where you can look up your own paper tape projects:
- The exceptional Exploratorium has a bunch of paper circuits projects
- Makerspaces.com has a number of good examples
- Sparkfun’s guide to paper circuits gives a broad overview as well as links to good projects (and a shout-out to Circuit Scribe! *blushes*)
- This Pinterest page has lots of fun examples
- The Circuit Scribe Projects & Tutorials section is chock full of paper circuit projects you can make with our kits; many can also be done with copper tape instead
One final lil’ tip – copper tape can be a little expensive. You can always use aluminum foil and apply a glue stick to the back side to stick it down to your paper. See our “turn the corner with Circuit Scribe” blog post to get a picture of how this works – the blog shows short sections of aluminum foil but you can use long strips as well.