Instructions hereI tested this method and it friggin' works! I've been afraid of etching for a long time because it usually involves using chemicals and stuff that I'm not up to.
My method to mask the enclosure is to spray it black and use my laser engraver to engrave away the paint, exposing the metal, which will be etched. In my case, I'm using a solid state laser (as opposed to a Co2 laser) and it doesn't seem to do as a good job of taking the paint off perfectly so the etching results aren't perfect. Once I invest in a proper Co2 laser, I'll be able to get super clean masks, getting clean etching as well.
If you can do the same vinyl method as the instructions suggest, then that will work great as well.
I used a 12V 1A power supply that I had laying around and soldered the negative wire to a big nail. I then taped the positive wire to the inside of the enclosure. Since the enclosure is sprayed on the outside, I put it upside down to prevent the inside of the enclosure from etching as well.
Here are some sample photos:
So you can see the middle isn't as good because it didn't etch as well there (because of the paint).
Sorry the photos are upside down, I don't know why!
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