Hi, well here I'm posting a little tutorial with some procedures I have being experimenting so I can etch metal the most easy and inexpensive way. This involves things we already have around and it is a non-toxic process, although I always do it outdoors.
MATERIALS FOR TRANSFERING PC DESIGNS TO METAL
a) Design: you can design anything you like but keeping in mind that it should be artline and if the design needs to be in a certain orientation --say has letters-- it needs to be printed flipped or mirrored.
b) Laser printer: deskjet printers won't work because the ink are water based --I'll post another tutorial about transfering images to wood--. When you print your designs for transfering you need to use the max darkness available, if the printer has "RET", put it on max/darker. I have very nice success always with my old HP Laserjet 1100.
c) Old magazines: you need glossy paper but not too thin because it will "bake" too fast. I always use magazine covers like those from The Lancet medical magazine, or Newsweek. It doesn't matter how colorful they are...their print won't transfer.
d) Acetone or nail polish remover: just the stuff our wives use...and while you are silently getting her little acetone bottle, steal a few cotton cobs Other thinners may not work. WD40, gasoline, mineral thinner, etc won't work since they will soak the paper too much and eventually won't melt the tonner.
MATERIALS FOR ETCHING
Steel or any ferric metal
a) Sand paper: while the metal needs to be pristine, mirror polish is a madness accept the transfer, so if you have a polished piece --like the blades I produce which are "mirrors"-- you need to tone down the finish a bit with say 500~1000 grits sand paper. I know it is a complex step and should be carefully or hours of previous polishing would go to the drain. So take your time and sand nicely.
b) Table salt: what we have in the kitchen, what the doctors say it is bad for our hearts but we just can't stop pouring it over french fries. Doesn't matter what kind of salt, thin or coarse, with iodine or not, although I never tested with marine salt --never seen that in our market anyway.
c) Water: plain normal water from the tap.
d) Battery charger or any direct current power supply: some people say a 1.5V battery works, in my opinion, I won't like to spend a day trying to etch something. My battery charger is 14V at 14Ah and it provides current to etch the blades I make very nicely.
e) Metal rod: any kind of metal will work. I actually use a rod from an old scanner, which has a chromed finish. It is ok since because it is chromed, it won't get the eaten steel crusted over it.
For etching copper:
Salt water electrolysis won't work with copper, so you need ferric chloride, the stuff used my electronic hobbists. As I want to keep my hobby on the lowest invest as possible I create ferric chloride with muriatic acid --toilet cleaner-- and rusted iron/steel --from old rusted stuff I found in a nearby coast.
TRANSFERING THE DESIGN
First you need to prepare the metal: clean it and sand it until you see almost a mirror. I use steel wool, sand paper, dish washing liquid, vinegar, whatever it helps me. If you have a mirror finish already then tone it down with some sanding. I found out a metal "says" it is clean when you put water on it and when draining it, it looks like a coat, ie, no "lakes" or drops.
Now you have your nice design --artline, remember-- done with Xara or whatever other program you like. Now you print it in your laserjet printer at top darkness, top quality, top everything. Keep in mind the orientation: if you put letters then you need to flip the design before printing.
Cut the design with some sissors leaving say 1cm around as bleed. We don't need any bleed but it allow us to apply the acetone beyond the design boundaries.
Place the printed design over the metal piece, facing the printed side to the metal and use a paper clip, a small piece of scotch tape or whatever you want to temporarly fix the paper to the metal.
Apply a cotton cob soaked with acetone over the paper. Don't rub but instead spot and press. Don't use too much acetone since it will run the melted toner. As a rule, I apply until the paper gets transparent enough I can see the printed design.
Keep the paper there and check by peeling a bit if the design got transfered or partially transfered. I have transfered ONLY with acetone ONLY over stainless steel. It transfered completly. Over other pieces I never get the full transfer done.
If the transfer didn't happened completly then you need to heat the piece: I tried with a cloth iron, no good enough. Tried with a damaged cloth iron sole, too hot. The one that worked for me was a stove: I just put the piece with the paper over it, over the lowest flame and let it heat the piece. The paper should change its color but NEVER bake it, it will bake the toner too. I would say it should get a very very slight tan.
Take the piece with some forceps or something --remember the piece WILL be hot-- and place it over a folded newspaper. If you can, place it inside the latest fold and then apply pressure over the piece with a spoon. Apply a lot of pressure by rubbing.
Then take the piece out and let it cool naturally or toss it inside a container with water at room temp. Don't rush it, just leave it there until you see the paper starts to desintegrate or at least to peel itself off.
Under running tap water, start peeling off the paper from the metal, using the finger nails to scratch it out. The transfered design SHOULD hold the nail scratching well, if it comes off, then it is not good for etching, so you need to go back to step one, removing the design with acetone.