Electro-etching 

In 1991, Nik Semenoff at a conference at the University of Saskatchewan in Canada described and encouraged artists to use electro-etching as a safe process to etch intaglio plates. During the late Eighties and early Nineties concerns were raised about the heath and safety of many of the chemicals and processes used to teach traditional printmaking in schools of art.   One hundred and fifty years after its original patent electro-etching was resurrected  as a potential replacement for acid etching. The focus of its re-entry onto the art scene was based not only on it being a safer alternative to traditional nitric acid etching but also on its cost effectiveness.

Electrolytic etching uses an external power source such as a battery or a bench power supply. It is an easy to setup and is a simple, cheap and safe alternative to using acid to etch copper, zinc, mild steel and aluminium.

No special equipment is required so it can be undertaken in a domestic or teaching environment. All that is required is an “AA” battery in a battery holder with leads attached and a switch. A two-litre beaker containing 250g. of copper sulphate made up to a litre with tap water (electrolyte), a small copper plate made ready for etching and clean copper plate or copper mesh to act as a cathode. The plates are secured facing each other in the electrolyte about 50mm. apart. The lead from the positive pole of the battery is attached to the plate to be etched (the anode) by a crocodile clip and the negative pole is attached to the other plate (the cathode).

 

  1. Advantages of Electro-etching
    The lines produced by electro-etch are clean, defined and are vertical to the surface of the plate.
    The line does not spread as it does with other mordants so there is no undermining of the ground.
    No noxious gases are produced by electro-etch that are also a cause of the undermining of the ground with other mordants.
    There are no waste products left in the line by electrolysis.
    Cross hatched lines are sharp and do not spread into each other and develop pits that ink can puddle in.
    Microscopic examination shows that the bottom of the line is rough, this roughness holds the ink in the line.
    Electrolysis can be used safely in an open studio.
    Because electrolysis works at room temperature, it is possible to experiment with fatty and other grounds that when take longer to break down than when being etched in acid or saline sulphate.
    The electrolyte is self sustaining and does not tire so accurate timing can be made for the depth of etch or aquatint.

Despite all the the advantages  electro-etching has over traditional acid etching and some of the  more recent less toxic alternatives electro-etching has never taken its place in the mainstream of fine art printmaking. 

The Cave’ Plate 45cm. x 28cm. electro-etched aluminium. Print size 62cm. x 40cm.
This larger aluminium plate was electro-etched and takes advantage of the textured surface that is revealed when aluminium is open bitten. Aluminium can only be safely etched with saline sulphate or electro-etch. The advantage of electro-etching is that the process can be more controlled, the line is finer and it does not undermine the ground as saline sulphate does.

After degreasing the plate was covered with a liquid hard ground, then the lines, including the cross hatching were drawn through the ground, the plate was then etched for the first time and the hard ground removed. The areas that were to remain white were painted out with liquid hard ground and the plate was etched for the second time to get the light greys and the process was repeated to get the darker greys.

Resources
Crujera, A. http://nontoxicprint.com/electroetching.htm
Crujera, A. (2012) Electro-Etching Handbook a safe non-toxic approach.
Available from Amazon.
Crujera, A. Home http://www.es.crujera.com
Green,c. Green alternatives to traditional printmaking https://www.greenart.info/green/
Pogue, D. (2012) Printmaking Revolution: New advancement in technology, safety and sustainability.
Pogue, D. Home http://www.cspoguegraphics.com