Etching and photo-etching

In etching, you draw with a protective resist that withstands the acid, and the bath corrodes only what is left exposed. The result is a design cut into the metal.

Steps #

1. Clean and degrease the metal.
2. Protect it with a resist (varnish, wax, vinyl or photosensitive film), leaving the design exposed.
3. Immerse the piece in the etching bath.
4. Neutralize, remove the resist and clean.

Etchants #

Ferric chloride is used for copper and brass; silver and steel use other, more dangerous acids. Electro-etching, with electric current and a salt solution, is a safer alternative.

Photo-etching #

A photosensitive film and a printed mask allow very fine drawings and lettering to be reproduced with photographic precision.

Safety #

Work with gloves, glasses and good ventilation, and neutralize acid waste and dispose of it according to regulations.

Step by step #

1. Clean. Degrease the piece thoroughly.
2. Protect. Cover with varnish or wax what must not be attacked.
3. Draw. Remove the protection where you want the design.
4. Immerse. Place the piece in the etchant.
5. Watch. Control the time and depth.
6. Neutralize. Rinse with water and baking soda; remove the varnish.

Tools and materials #

• Etchant (ferric chloride or diluted nitric acid)
• Protective varnish, wax or resist
• Plastic or glass container
• Gloves, glasses and ventilation

Common mistakes #

• Leaving the piece too long: detail is lost.
• Grease on the surface: the etchant acts unevenly.
• Mixing acids without knowledge.
• Pouring the etchant down the drain.

See also #

• Hand and laser engraving in jewelry
• Texturing metal surfaces in jewelry
• Copper