Printed Circuit Board
After the board is cooled, you can, CAREFULLY, remove the paper off it. In case the paper is TOO "glued" to the board, you can put on water and let the water help to remove, but, generally that is not needed.
Excellent! The paper comes off the board without leaving almost NO toner on the sheet! Check below.
The board is almost ready to be etched. Correct any tracks if needed. You can use a felt tip pen, the kind used to write in CD-Rs or plastic. You can also help to clean the pads holes which sometimes get clogged with photo paper stuff and eventually won´t corrode.
Don´t worry while doing any changes to the tracks sine the toner WON´T COME OFF without a good effort! Now put it on a plastic container for etching.
NOTE: IRON PERCHLORIDE can be obtained in Electronic Shops (here in Brazil). I prefer the one in SOLUTION, since it´s less work to do and less mess. BE CAREFUL WHILE HANDLING IT: Perchloride OXIDIZES OR CORRODES COMPLETELY almost ANY kind of metal; it stains clothes, floors, wood, your skin and many more =), but plastic and glasses. Here´s my disclaimer... =) Handle it with care so to don´t spill. If eventually a bit gets on your skin do not panic: WASH PROMPTLY IN FRESH WATER. It is not exaclty an ACID, but can deeply stain skin if you don´t wash right away.
Now fill the container just enough to cover the board. Corrosion (like we say here...) or Etching (like you say there) takes something between 15 and 30 minutes. If the container is gently shaked, it can accelerate the etching a great deal! Temperature also has influence: the solution at 60 degrees celsius has the TOP-POWER effect for etching. You can put the container shown above into another container filled with hot water. Etching will take no more than 10 minutes if done this way! In the picture below I used a 60w lamp very close, but the hotwater method is better.
You can also stir the solution using a tweezer and the board. Board will corrode
a lot faster:
última atualização: 03/06/2004 17:07