Electro-erosion for amateurs?

Bruce Simpson's site has an article on etching reed valves;

Black asphaltum was traditionally used as an etch resist. For minor touch-ups, the latest thing seems to be Staedtler permanent felt pens in red ( red seems to stick the best). Both available at your local art supply store.

It's kind of a trial & error thing, depending on the metals used.

Hell, that's almost exactly the same method I came up with myself, except that I was much wimpier with how much power I pumped into the electrodes. Looks like I just need to try again with a lot more juice. I'll rig up some sort of current-limiting circuit & maybe 48VDC.

Thanks very much for the info, Bart, it's much appreciated.

Now that's interesting. Great piece! It sounds like basically you hook up your workpiece and the other electrode backwards from the way you do it when you're doing electrolytic derusting, so that the workpiece is the anode for the etching setup. Any piece of the workpiece that is exposed to the solution will be quickly rusted away, or etched away as would be nicer to desribe it.

Never knew about that. I'll file that one away. I'm still planning to test the use of sheet lead electrodes in electrolytic derusting, but haven't gotten to it yet.

Grant

valves;

This article presents information on etching thin ferrous sheet. Will such a technique (12vdc in dilute sodium chloride solution) work with thicker material or non-ferrous sheet?

Gary

That is what we used for etch resist back when I was in high school (let's see I was a freshman and graduated in

49 so that was about 61 years ago) We did Copper and Aluminium trays beat in a wooden form and etched designs on them. I think the one I made is still back in PA at my brothers place. ...lew...

Yes.

Good question! - If there are any chemists or electroplating experts reading this group, I'd love to see any comments you might have.

What I /do/ know, is that it'll be very dependent on the type of metal. AIUI, the process is essentially reverse-electroplating (transferring ions *from* the workpiece, instead of *to* it), so I imagine you could look up the appropriate electrolyte for plating the metal concerned, & use that safely.

Google on "electrolytic etching" along with "copper" .. easy as pie

GWE

Good advice. It turned up lots of useful pages.

Thanks Grant. :)