Graphite circuits are a fun and potentially useful trick to create paper thin circuits that can power electronics, although they work best for LED’s, due to the low power consumption and inefficiency of the circuit.
- A piece of paper
- A graphite pencil (not the #2 pencils you used at school when you were a kid, but what “artists” use that’s pure graphite. If you don’t know what I mean by that use the picture above for a reference. Also, if you still go to school you may be able to borrow one from your art teacher).
- A battery or electrical source
- An LED or other electronic
- Tape (optional, and it’s to hold down the battery wires or LED to the lines)
- Volt meter (also optional, just so you know if a current is running through the line and how much)
How to Make the Circuit:
This is perhaps one of the easiest projects you may find on intractables to complete. It’s as simple as drawing the circuit onto a piece of paper, and then connecting the battery and LED to the circuit, and you’re done! You want to be sure to make the lines plenty thick when creating the circuit though, so that it’s a large path for which to allow electricity to flow through it. You should pass over the same line five to ten times roughly, dependent on how hard you push on the paper
It’s also best to draw a circle on the side where the battery and LED connect to the paper (fig. 1). This greatly helps with the flow of electricity, producing a much better current.
Why it Works:
Graphite, although a poor conductor, is still a conductor, thus has the ability to conduct electricity. Its most common use (that involves electricity) is in resistors, which is why its ability to conduct electricity drops greatly the longer the line is.
I’d like to remind you all about being sure to use a pure graphite pencil and to make the lines exceptionally thick. Failure to do either of these (especially the first one) and the circuit will not work.