PCB etching as an artwork

I used to etch my own PCB with the pencil method, i.e. very ugly and wide traces but low cost and easy enough for the average project.
I always tought that PCB etching must be the modern counterpart for aqua fortis, the ancient artistic etching technique involving resin as resist and vinegar (or other low-tech variants) based etchants.
Ironic enough, i didn't really attempted any artwork with etching process until i left the pencil drawn board to start using toner transfer based techinques.
The first time i realized that the toner could be easily transferred onto other surfaces was by mistake: i was cleaning something with acetone using an old laser-printed sheet as protection for the desk, with printed face downward: i had the entire document printed -mirrored- on my desk. Even now, after having widely experimented the solvent-based toner-tranfer techique and having realized that it's too difficult to perform in the gratest part of situation (= on the greatest part of surfaces that are not my desktop) I still have it on my stack of things to play with again, as soon as i get some free time.
I had some sheets of ad-hoc toner transfer paper, but i was reluctant to use them for two good reasons:

  1. they costed 4 euro each
  2. my laser printer (old, ugly, unsupported, broken, but i still have 4 toner packages...) has a defect that causes spots to be printed on a fouth of the sheet so that fourth is unusable and ruined
So i investigated more about heat-based toner-transfer and found a suitable solution:
  • use inkjet-intended glossy paper with the laser printer
  • iron it on the board for exactly five minutes at maximum heat with no steam
  • leave it cool
  • submerge in wather for another five minutes
  • scrub glued paper with an old toothbrush
It works. And additionally, i'm able to scratch the toner away from the paper before the ironing, so i can erase those spots my printer does.
Here's the story: the first attempt with this method was not a circuit... i had some cheap copper board and i thought that if this method would have been good for artworks, then it would have been perfect for PCB, too...
So i opened a photo, i lowered the resolution, i reduced color count to 2 (black and white) and then i raised resolution again to have somewhat like round pixels: it was not so difficult, i simply had to play some time with parameters (expecially with the color reduction and dithering creation functions).
The print was great, and even only the toner transferred without yet etching the board was very good looking.
The resulting board is very sharp and definite, because the toner was so firmly stuck to the copper that cleaning it with acetone took me about half an hour.
I have to admit that - once cleaned from toner - the board is not so good looking because:
  • copper is shiny, making bachelite appear like the dark color (so i should have printed the photo in negative)
  • bachelite has marks from the producer merged into the board, so if you put a light under the board you can see them
Pictures on this pages are from two different attempts, the first with plain paper, the second with inkjet glossy paper.

Anyhow, this was an experiment, and next time i could focus specifically on the art part and produce something better.
Just a few ideas are:
  • using the toner as the picture on some cool surface, without any other process
  • using an etched board as a stamp, just like in rotary presses
  • etching a higher copper sheet and maybe use it to burn the photo on a piece of wood
  • etching some other metal that gets darker in etched spots