Intro: Reusing Ferric Chloride for PCB Etching at Home
I feel PCB etching is one of the most required skill for a DIY electronic Hobbyist. During the etching procedure, you might have obviously heard of a useful chemical known as Ferric Chloride. You might have even tried etching a custom PCB by sponge rubbing method. People normally use the chemical just once and dispose it off. But in this instructable, I will teach you how to "REUSE" this Ferric Chloride solution and save your precious making "COSTS" right from your home with very less apparatus.
Most of the methods other than the method I used are relatively slower processes. So my method also saves 90% of your valuable "TIME".
Step 1: Materials Required
Please don't feel bad if I make your Kitchen a temporary Chemistry Lab ;-)
>>A Metal Plate
>>A Good Quality thick Plastic Container (Usually a grade 5 plastic and the one which in which your PCB board fits)
>>A Gas Stove for Fire
>>Reusable Ferric Chloride Solution
Step 2: To Start With
Fill a metal container (Plate) with water and start boiling it.
Place the plastic container with ferric chloride on the boiling water .
Reduce the flame so that its job is to just heat the chemical indirectly.
Step 3: Immersion
Immerse the PCB board that you have created using a Toner Transfer method into the ferric Chloride solution.
Since the rate of this reaction gets damn faster as the solution gets heated, you could expect the etching process completed within 5 to 10 minutes!
Its quite faster than any other method online that uses a PCB etching process using ferric chloride at home.
Step 4: Final Step
Since we are using a plastic container to keep the chemical, we can easily hold it with bare hands and stir it after every minute so that the copper precipitate that is accumulated over the board spreads out.
Repeat this procedure until the Board is free from any copper that is naked.
Store the ferric chloride in the same plastic container until next use.
Step 5: Tips
>>You can even choose the plastic container according to the shape and size of your PCB.
>>Solder the pads (and paths) with a layer of lead so that the tip of the driller stays well within the hole.
>>If possible, try to separate the copper precipitate from the ferric chloride solution before reusing it next time. You can do this easily by pouring the top layers of the solution into an another container and disposing the bottom most copper precipitate layer.
>>I have used a Unique Method of Recycling Ferric Chloride at home by turning your kitchen into a temporary laboratory. ;-)