I etched my first PCB today. It came out very well (considering that
it was the first one I did). I used a mix of different techniques
which all worked out well for me in the end.

To begin, I made a simple design for a quick prototype board for my
dsPIC33FJ128GP802. The board itself is very small, just about 1.5" x
2.5" (off the top of my head). I had a large sheet of copper clad
board so I had to cut out the small piece that I would be working
with. This part was not fun at all.

I printed out my design and traced out the rectangle off a corner of
the large copper clad board. I then used a utility knife to score the
sides of my design. It took a while to get deep enough to snap. Then I
used metal shears to cut one edge of the board. This was an unclean
cut and damaged part of the large board and slightly warped the copper
on my design. No big deal. I then stuck the remaining part of the
board into a vice (with paper towel for padding) and snapped the
remaining edge. I then sanded the sides with a piece of (metal
purpose) sand paper. I was then left with a small rectangle of copper
board ready to be used for toner transfer. I used nail polish remover
to clean the board. Then I used soap and continued to clean the board.
Finally, I took some fine sandpaper and scrubbed the board clean. The
board was now ready for toner transfer.

>From suggestions from my other thread, I tried a different printer. I
used the same paper (staples glossy paper for laser printers) that I
had tried before. I set the print quality to the highest setting and
configured it to deposit the most amount of toner possible. I then cut
out my design and headed over to my clothes iron. I preheated the
board by placing a blank sheet of paper of my board and ironing it for
about a minute. Then I carefully placed my design onto the copper
board. It stuck instantly. I ironed it for about 2 minutes. (60 of
those seconds I just left the iron on top and went downstairs to get a
snack). I didn't do anything special. I just pressed hard (but not too
hard) and went over it with the tip of the iron. I then filled a small
sandwich box with water (about body temperature) and dropped my board
(with the design paper still stuck on it) into the water. I headed
over to my local grocery store to get some groceries for dinner. By
the time I came back, the paper was soft enough to peel and rub off
with my thumb. Some of the toner smudged, but overall, the quality was
pretty good. The toner had definitely stuck well this time.

Now for the etching part. I took a small dish washing sponge and cut
out a square about 3" x 3" x 0.75". I poured about a table spoon of
ferric chloride on the sponge. I put on my vinyl gloves and started
lightly wiping the board with the sponge. The copper started to come
off instantly and turned the bright-yellow sponge nearly black. I kept
wiping for about 2 - 4 minutes and eventually, all of the copper (that
was not protected by the toner, of course) came off. This sponge
method turned out to be very fast, efficient, clean and easy. Also
saved a lot of ferric chloride. I ended up with a very well etched
board. It was easy to see when it was finished and the etching
solution worked very fast and etched very cleanly. Then I washed the
board and inspected it (and admired it). It would have been perfect
had the toner not smudged. The etching process itself was very clean
and precise. The only trouble was the toner. I need to find a better
way to put etchant-resist onto my copper.

I then took the almost-finished board downstairs to drill. This part
was not fun as well. I drilled about two holes then gave up because
all I had was a clunky drill and very brittle drill bits. This
drilling part is impossible without a proper drill press. A CNC
machine would be ideal (even a crude one would do the job
sufficiently). So there ya have it. An almost-finished PCB.

Looks like I'll need to find myself a drill press.

To all the helped and gave advice, thank you very much. This process
turned out to be fun and educational and I leaned a skill that I'm
sure I'll find very useful in the future. The whole process took less
than an hour and gave very good results. The results would have been
perfect if I had a better method to transfer the toner (via laminator
and a good printer, maybe) and a CNC machine or at least a drill
press.

What I was most impressed with was the sponge method of etching. Only
a table spoon of ferric chloride was required and none of that
heating/agitation nonsense was needed. The process was clean and
efficient - no spills, little to clean up afterward. So if there's any
of you still pouring the etching solution into a tub and
heating/agitating, I highly recommend that you give the sponge method
a try. It's awesome!

-- [ solarwind ] -- http://solar-blogg.blogspot.com/
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