Printing and Etching Circuit Boards
Printing your Board
Turn on the E260 South printer, and put one of the paper-width aluminum sheets into the feed tray. There is a horizontal line on the sheet which should be lined up with the clamps of the input tray.
Using PDF or Image viewing software, pull up an image of your board's pads and traces. You can see the size and location of the printed image on the aluminum sheet. This is where you will want to center your PCB. Make sure that the image prints at the correct scale. Some programs will try to change the size on you. When using a PDF, if the image is off to one side, you can fit the window around it and choose "Print Current View" to center your image on the aluminum.
Scrub your selected PCB material with powered stone (available in the etching lab) to remove all fingerprints, dirt, and markings. Use a dry paper towel to wipe all the ink off of the aluminum sheet, then use tape to secure your PCB in the previously tested position. Use some short wires to make a connection between the copper top of your PCB and the aluminum sheet.
If the image prints incorrectly, either in the wrong location, or with incomplete traces, you can use a dry paper towel to clean away the ink and adjust as necessary. Once you have a functional image, use the oven in the Projects Lab to harden the ink. Approximately 1 minute at 100 degrees Celsius should do the trick. Your board is now ready to etch.
Etching your Board
To work effectively, the etching solution must be agitated. Make sure the compressed air hose is connected. The etching tank has a number of slots, so several boards can be etched at a time. Choose a slot, and carefully insert your PCB into the attached gripper. Fit the slot back into place.
The time necessary to complete the etching process will vary based on the strength of the solution. Check on the progress in five minute intervals, and remove from the etching solution when all unwanted copper is gone.
Use a q-tip or paper towel dipped in acetone to remove the ink. If you have a ground plane, or a large number of traces, you might find it useful to leave the ink over these areas in place, and only remove it from your pads.