This is a short tutorial on how to etch your own PCB (printed circuit board) using a mixture of muriatic acid and hydrogen peroxide.

Here is what you need.

1. Some kind of software to draw out your circuit board traces. I recommend Express PCB. It’s free just google it.
2. A laser printer.
3. A blank piece of copper clad circuit board.
4. Some muriatic acid
5. Regular 3% hydrogen peroxide.
6. A plastic container big enough to lay your circuit board in.

Once you have your circuit drawn out the way you want it go ahead and print it out. You have to use a laser printer, an inkjet printer will not work for this. Now take your blank circuit board and clean the copper surface with a scotchbrite pad and lay your print out of your circuit toner side down on the copper. You may want to tape it in place so it doesn’t move. Next take a regular clothes iron on its hottest setting with the steam turned off and apply it to the back of the printed area on the paper. Make sure you use firm even pressure and go over the entire printed area. The goal here is to make the toner on the paper melt and stick to the copper. Now take the board with the paper still attached and soak it in water till the paper becomes soft and you can gently remove the paper leaving the toner on the copper. You are now ready to etch your circuit board.

To etch lay your board in the bottom of your plastic container. Mix your acid and peroxide in a ratio of about 2 parts peroxide to 1 part acid and pour it in making sure you cover your board with about an inch of solution. Now gently rock the container to keep the solution moving over the board. You will notice the solution slowly turning green as the peroxide oxidizes the copper and the acid dissolves the oxides. The toner will protect the copper under it from being eaten away. When all the unprotected copper in gone remove the board with some tweezers and rinse the solution off with water. Use some scotchbrite or acetone to remove the toner.

The final step is to drill the holes and you just made your own printed circuit board.