Step 15: Etching - The Procedure
You should have checked it over and made sure that all of the traces are completed, and there are no chips that would make an incomplete circuit.
If there are any chips or scratches, fix them with a Sharpie as described earlier.
Lets start etching!
Gently place the board into the etching solution.
You will notice that the etching solution begins to change color.
This is the acid reacting to the copper and starting to dissolve it.
Agitate the container gently, so that the etching solution mixes over the submerged board.
Use a paper towel to wipe the board while it's submerged.
This helps along the etching process.
After about 4 minutes, you will notice that the copper will begin to dissolve.
Continue to wipe areas where there is still copper.
After about 5 minutes, your board should be completely etched.
The etching solution will have changed to a green color after reachint with the copper.
Remove the board and rinse it in the second container, the one that has just hydrogen peroxide.
This will dilute the remaining acid.
Now, it's not the best thing in the world to do, but we've diluted any solution still clinging to our board and most of the copper that has dissolved into the solution is diluted as well. So... take your board and rinse it under some water.
Here is what you should have.
You will notice in the photo attached that there is still some copper in the top right corner.
This should be ok.
But if this happens on your board and you want to remove it, just gently sand it off. Be careful not to sand off anything you don't want to!
The final step is to use lacquer remover to get the toner off.
Put some lacquer remover on a paper towel and wipe off the toner.
Do your best to get all of the toner off.
Your board should look like the final photo attached.
Rinse this puppy off once more and get ready to drill the holes for the components.