DIY Conductive Paint Recipe
If you have been working with kids and paper circuits you might be running into a frustrating problem – the copper tape wires you lay down in your paper circuits don’t make good contact with each other.
This can lead to your paper circuit not working, even though the physics and circuit building portion of it is in order. Talk about frustrating, especially for young learners!
Why doesn’t the paper circuit work?
If the wiring, polarity, and battery charge are in order for your paper circuit it is likely that the problem is with the conductivity of your circuit. In an ideal paper circuit, you would bend the copper tape around corners. In reality, however, a lot of us use strips of tape that we layer to make turns.
When we do this we are asking the electrons to travel through one piece of the copper tape, then up through the sticky glue part, then into the next piece of copper tape.
This wouldn’t be an issue if the glue was conductive like copper is. But it isn’t. This puts a huge resistor, or electron traffic jam, in your circuit and often the battery doesn’t have enough push to get them through. Without enough push, the battery can’t create a current which means your LED won’t light up.
Should I make conductive paint?
Absolutely. If your paper circuit isn’t working well and you have tested all of the regular culprits (LED polarity, battery, short circuit etc), then DIY conductive paint might be the perfect fix for you.
Graphite is conductive, and by making the graphite conductive paint you are giving the electrons a better path from one piece of copper tape to another than the sticky glue/tape bottom. Best of all, this DIY conductive paint recipe is cheap, easy, and non-toxic so kids can use it.
How to make conductive paint recipe
- Find a small airtight container, like a small Tupperware
- Add in a small amount of Elmer’s glue (we used white, not clear).
- Add 2 teaspoons of graphite powder to start and mix well. Graphite is electrically conductive, so this is the ingredient that makes your paint conductive.
- Add in more graphite powder, a little at a time. You will need to saturate the glue with graphite powder. At one point it will look clumpy, but if you keep mixing it will slowly go into a very thick conductive paint.
- If the mix is too thick add a little more glue. If it is too thin add more graphite. The final mix should be fairly thick, but still paintable.
If you are having trouble making your DIY conductive paint, watch our video below. You can also buy conductive paint if it feels overwhelming, but really, you can’t mess up this two-ingredient DIY cheap conductive paint recipe!
Use your DIY conductive paint with our fun paper circuit projects.
Why DIY Conductive Paint?
Paper circuits can work better with the addition of cheap conductive paint.
Working with circuits can be difficult, especially when you are creating circuits with kids, and want to find a safe alternative to breaking out the soldering iron.
To get around the soldering iron we have to give up on the conductivity at the connections or joints between two pieces of copper tape or between copper tape and metal legs. Adding electrically conductive paint to these joints can help your circuit function better.
Why is copper tape hard to use in circuits?
The copper tape has an adhesive on one side of it. This is what makes it stick to the paper as you put together your light up cards or conducting critters. When you join the copper tape together, there is a thin layer of this adhesive that the electrons have to make their way through.
This acts like a big resistor and often will diminish the light your LED gives off.
To get around this thin layer of adhesive we could opt to solder the two pieces together, but that would require a soldering iron, which is not safe in very young hands and needs a lot of oversight in moderately young hands. I started teaching my daughter soldering when she was 5, but it is certainly a very careful activity with a lot of layers of protection for her.
Another way to get around the thin layer of adhesive is to try and use only two pieces of copper tape, that you bend and curve around the circuit diagram. This can also be troublesome, especially for younger hands. The way you bend the copper tape is important, and it doesn’t solve the issue of the joint between the copper tape and any metal legs.
You might be wondering, how can I make my paper circuit work better? Use our DIY conductive paint.
There are a few products out there similar to gels that are known as electrically conductive paint. These premade gels often work better than the conductive paint we will make, but ours is far cheaper. It is the difference between about $37 per ounce and $1.40 per ounce.
Our DIY conductive paint is 25x cheaper than store bought.
For me, that is a huge win. I run a ton of community programs and teach afterschool science around the area, so the thought of it being 25x cheaper is huge. Another reason why I prefer making my own conductive paint?
DIY conductive paint is non-toxic.
That means kids can be around it repeatedly and no one needs to worry about any hazardous side effects. Some of the electrically conductive paints online have their own MSDS sheets. Others use various solvents that can be smelly – certain types never fail to give me a migraine.
DIY conductive paint made out of glue and graphite is safe.
I have no idea what commercially available conductive paint manufacturers use in their products, but I have come up with a recipe that works for the circuits my kids make. All it uses is Elmer’s glue and powdered graphite.
What works better than powdered graphite in electrically conductive paint?
I currently have no idea, but I am always on the lookout for a better recipe and will update this post if I find one! One idea is to add metal filings to the mix, although then I would run into worrying that kids would get metal splinters.