Etching a PCB for the IEBus Module
I completed the etching process of my first printed circuit board tonight. It took a lot of work just to learn how to use the Eagle software to produce the board layout but once I had it done I printed it onto some generic glossy laser paper. Next I took it downstairs to the ironing board, and armed with a piece of cardboard to stiffen the ironing surface, the heat from the iron began to transfer the toner from the printed piece of paper to the blank copper PCB.
After about 4 minutes (read online that 4 minutes was a good time to ensure a good transfer) I took the board with the paper now stuck to it, and put it into a plastic container filled about an inch high with hot water. Immediately I began to see the paper coming away from the copper and forming little bubbles between the paper and the board. Finally, after about 30 seconds of watching the water soak into the paper, I grabbed the corner of the paper and pealed it off like a sticker. Most all of the paper came off leaving behind the toner and a little bit of the paper that rubbed off with my thumb very easily.
Next it was time to put the board into a bath of etchant. I went all cheap and purchased the little $15 kit from RadioShack to test all of this out, but I plan to put together an acrylic bubbler along with some of that nice Ammonium Persulfate that is see through. The board sat in the etching chemical for a little over an hours just because I didn’t feel like babysitting it and went to watch some boob-tube. When I came back the board was done and I transfered it back to the water to deactivate the chemical.
Now that the copper that I didn’t want is gone, all thats left is to clean off the toner. This was handled by some of my wife’s finely smelling Acetone (finger nail polish remover) and a good bit of rubbing with a paper towel. The finished result looks like this:
Now all that is left is to drill the holes and mount all of the components. Next time I do this, I think I am going to go with all surface mount components, so I guess its time to hit up digikey again.