Friday, 30 August 2013

Etcher – Instrument Panel design – Part 2

Well, I’m out of state for a couple of days so I can’t really do anything on the Instrument Panel other than plan and speculate.

Also, I’ve realised that I don’t have the tools in my flat to be able to cut the brass plate, so I have enlisted the help of a mate who has some tools.

I’ll be taking the stock over to my mate early next week and I’ll get the stock cut into the panel that I want and some off-cuts. I’m going to use a piece of the off-cut as the cathode for the etcher. This will just need to be bent so that it hangs over the lip of the salt bath and the negative of the etcher will clip to it.

I still need to think about how the anode will connect to the work piece. I have a couple of options:

  1. Solder a piece of wire onto the back of the work piece and then paint the exposed wire (so it isn’t just corroded away during the etching process);
  2. Leaving a piece of metal extending beyond the piece required for the end resulting piece;
  3. Braze another piece of brass onto the work piece.


Option 1 and 3 are kinda the same, the only differences are material and method of connection. Option 2 would be OK too, but leaves me with more waste.

I think that option 1 is going to be the most practical solution. Soldering on to the back of the work piece will leave a mark on the back, but it is going to be in a place that won’t be seen by anyone (unless the instrument panel is removed). I’m going to use some solid core copper wire for this, it should be reusable, so it won’t be a resource problem.

I’ve seen some baths where the work piece rests in a “cradle”, but I think that this is only really used where the etch is achieve with acid, not electricity. This could work, in theory, but in practice, the point where the work piece is in contact with the cradle it will need to be exposed, and the cradle will need to be exposed to the bath too, so both will be etched. I think that the cradle would need to be replaced periodically and the contact point on the work piece would have to be trimmed of after the etch (so it would have to be additional material on the piece … probably not all that practical.

Well … that’s probably enough talking about it for now. As I can’t really do anything interesting, I’m going to park this article until next week when I am back in the state.


I have handed the brass over to a mate to cut-out for me. I should get it back in a couple of days … not a big job, just other things in the way.

When I get the cut brass back, I’m going to file the edges and make it smooth so that it doesn’t scratch my iron.


  1. Depending on the size of the piece, you could use gaffer tape to adhere the wire to the back of the work piece.

    1. Thanks Chance, that's a good idea. I'll give that a go. Of course, gaffer tape (presumably you're talking about cloth tape) is not really waterproof. However, the adhesive on the tape should provide enough of a barrier. I don't see any good reason not to try it.



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