sounds like an ex gf i had. :barf: :barf: :barf: im sure you know the feeling too. does the voltage you use for an etch vary from each type of steel? whats a good voltage and amperage to use?
Actually, no, I never dated a girl with a nose wart, though I did date one with...well, nevermind.

You get carried away with these things too easy.
I have this Marking Methods unit in this kit:
http://www.markingmethods.com/mark300a.php4
When it came time to choose, all I knew about were this unit and this handheld gizmo whose appearance reminded me of an electric razor. I opted for the high priced spread and have never been sorry. I can burn my logo deep enough that I could file someone's knuckle off with it if they'd hold there finger still long enough.
I don't remember the voltage/amp settings of it's 5 "levels" of juice. It offers quite a range, and can burn a stencil easily. It "sizzles". I don't remember the specs, though if I remember this thread tomorrow I will see what the manual says.
There are various electrolytes optimized for different steels and other metals. Proper choice of electrolyte is as important as the voltage setting. Likewise, stencil quality varies. Some manufacturers work better than others.
Getting the etching down has a little bit of a learning curve. There are tutorials, and indeed a DVD by a gent named Bob Warner that details building a unit. Google Center Cross Instructional and find a bunch of training DVDs for knifemaking tasks.
Hope that helps.