Today, I decided to perform some tests on the Toner Transfer method for etching your own PCBs. I took the basic idea from Thomas Pfeifer's site. I gathered all the required materials, and started with a simple, ATtiny 2313 based circuit (done in Inkscape %-) that some day shall end in a midi mapper, allowing me to play drums in Blofeld's multi-mode with my channel-restricted MPD18 (one channel per bank). I'm also planning on mapping continuous controllers to different CC ranges (or CCs at all), but the software is still way down the road.

What I've managed so far, and what I wanted to document before I drop into bed, or, before I scrap it tomorrow, is my first attempt to toner-transfer a printed circuit onto a circuit board:

It a part-success, part-total-failure result. As you can see, a lot of the detail is there, even the fine, 0.3mm line-width "edg" logo in the middle is totally intact, and with a bit of luck, I might even get smaller than this. But you will definitely see the broken lines on the right, one even ending nowhere, right where there was supposed to be another hole for a resistor's pin. I was a bit too soft, probably. I take it, I didn't turn the iron up hot enough. Either that, or I was a bit too rough when peeling the paper off. I'll try it with more heat and care tomorrow.

Materials used: Brother HL-2030 laser printer, and the sleeve from the CD box of the worst game I ever actually bought: Neuro Hunter. Seems that I finally found a use for, well, at least for *some* parts of that thing. ;)

UPDATE 1: I'm getting better at this. This one is still not perfect, especially considering that I managed to double-flip the layout the whole time (plus, there was a bug in one of the circuits), but at most of the toner is staying where it's supposed to. I also switched to the Reichelt catalog's paper, as Thomas did. It's awesome for this kind of stuff. The paper is just thick enough to not get jammed in the printer, and thin enough to pass on the iron's heat without any problems. It's very easy to peel off, gets instantly soaked by the soap water, and the coating is just fine for carrying the toner.

However, I had to add some more graphics to the outer edges since I still have some problems with details there. The soldering pads on the far left and right edges got rubbed off constantly, so I decided to put something useless there, that probably noone will miss.

UPDATE 2:Not perfect, but DONE! :-) I can only spot two minor flaws in this one. The one bugging me the most is a small spot on a circuit path where the toner didn't stick. However, there should be enough copper left for all the volts and amps crossing this path. And the other flaw is actually adding to the raw graphic appeal of the circuitry. I didn't render the SVG in a high enough resolution. So, it's a bit blocky. But hey, it'll be fine electrically.

UPDATE 3:Got it etched. My first hand-made PCB. With PCB as in Printed Circuit Boad. Note the emphasis on printed. I mean, I do have another board with an etched layout, but that was foto-transfered, and not actually even printed. I glued it together with tiny pieces of tape. And I didn't actually etch it. My teacher did that. So it doesn't count anyway. Oh, I'm so happy... :-)

Now, all I have to do is tin it, drill a couple holes into it, solder the components and program the 'tiny. And, of course, bring the etching bath to the toxic waste disposal. And get more of this stuff. I have a lot of other plans for self-etched PCBs. :)