Basically you combine vinegar and salt, attach the item to be etched to the + of a 9V battery, attach a q-tip to the - pole (exposed wire wrapped tight around the cotton part), dab the cotton in your salt/vinegar mix and then paint on.
Seems like a bit neater than masking and immersing in diluted FeCl.
interesting. might be worth an experiment. i wonder if aluminium works better or worse that stainless steel?
btw have you seen the andy warhol 'oxidisation series' (aka 'piss paintings'). might some be potential in that (perhaps not for the faint of heart)?
on a tangent, i've done a lot of wet-process b&w film developing and printing in my time and have been wondering lately whether any of those techniques, even really low-fi early techniques (the daguerreotype and albumen prints) could be manipulated for the purposes of box decoration.
How easy is it to get a deep etch with that technique? It looks like it etches pretty cleanly, which is always a challenge with FeCl - it can be tricky to get it diluted just right so that it doesn't boil and make a huge dangerous mess with large pieces of aluminum. But is it quick? And can you get a nice deep etch?
Well, I never tried a different way, so I can't comment; I like etches, but I don't like using acids and tone transfer techniques... I use perfboad for my builds too.
I just put some white electrical tape on the pedal, draw what I like, then use a cutter to remove the inside of the figure. Once the mask it's done, it takes two/three minutes to etch. It does not get so deep, but it gets quite clean.
Try it on a piece of aluminum and see if you like it, but forget such professional results you see on the picture tread of diysb.
i found this website last night looking for ideas for mini-amps and thought the design element of what this maker was doing was quite interesting, so posted this link in the amp section yesterday because i thought it might inspire like-minded souls here. but as he appears to use the approach demonstrated above (about a sixth of the page down: battery, wires, acid in hypos... am assuming they're not recreational) in a context that directly relates to our purposes, i thought i might post it here too.
definitely worth checking out his design process notes and experimentation for his mini-amp builds. lavishly documented and well-researched. reads like a coffee-table book for the aspiring diy builder. impressive i think.