Etching metals with electricity
There is a much safer alternative, and that is electrolytic etching. Basically, the metal you want to etch is made the anode or ( ) electrode and a piece of the same kind of metal is made the cathode or (-) electrode. These electrodes are hooked up to a DC power source like a car battery charger or plating rectifier. To get a better picture, visit my electrolytic rust removal lens to see how a typical electrolysis setup can be constructed.
The metal ou want to etch still has a resist on it but there are more options since the mordant is less aggresive. For electrolyic etching, you can use a metal salt that is of the same metal that your etching such as ferrous sulfate for steel, zinc sulfate for zinc, and copper sulfate for copper and brass. Some people use strong solutions of sodium chloride or rock salt. Note I did not say table salt in that it contains additives that would interfere with the etching.
Ordinary table salt is not recommended due to the additives. You are better off with either Kosher salt or rock salt for ice cream making. Also, you want to use distilled water and not tap water.
Iron sulfate for steel
Links and resources
- Nontoxic Print
- A printermakers website using newer ecofriendly and less hazardous chemistry to etch metals such as aluminum, zinc, copper, and steel
- Steampunk Workshop
- A comprehensive website covering techniques and resources needed for electrolyic etching of brass with copper sulfate.
- Green Art Info
- A website dedicated to the history and development of electroetching metals without acids
- Electrochemical Etching With a Microcontroller (hackaday.com)
- Metal Working Techniques Part 5: Etching (eirny.com)
- Electrolytes – The Battery of Life (uckeleequine.wordpress.com)
- High Quality (and Safe) Nickel Plating (instructables.com)
- Zinc chloride Production and application (hong24608.wordpress.com)