• Electro-etching advantages
• Electro-etching disadvantages
Electro-etching Advantages
Electro-etching offers us such an exciting alternative to traditional acid etching that I make no apology for reiterating some of those advantages here:
• The electrolytic bite produces an impeccable and delicately etched line.
• The bite occurs perpendicular to the surface of the plate, and therefore results in very clean and bright lines.
• The electrolytic bite does not undermine the metal (foul bite) under the layer of protective varnish, avoiding damage to the edges of any resists.
• Cross hatched lines retain their integrity and do not tend to unite during prolonged biting.
• Electro-etching is highly controllable and therefore consistent. Using the same conditions i.e. the same electrolyte concentration, the same distance between anode and cathode, same time and voltage, means that the depth of the etched lines will be consistent and have the same features.
• In contrast to what happens with acid baths where it is necessary to extract the plate immediately to stop the etching process, in an electrolytic bath, etching stops when we flick the current switch off on the power supply. Plates can remain immersed for short periods of time with the electrolytic unit turned off, since corrosion does not continue. (Note: Over longer periods, the electrolyte can penetrate between the plate and contact-strip causing the plate to drop to the bottom of the tank, or lift the resist.)
• At the bottom of etched lines the electrolytic action generates a rough surface in the metal which holds the ink extremely well, even with wider lines.
• An electro-etching produces a uniform porous structure on a bare metal surface (a surface without a resist) that holds the ink. I have called this effect electrotint. It is similar to traditional aquatint, but to obtain a micro-dot effect you do not need to use any of the traditional toxic materials of aquatint sprays and powders, rosin or asphaltum.
• Electrolytic solutions do not generate fumes or toxic gases during the etch or when they are kept in the tanks while you are not etching.
• Etching with electricity does not generate toxic gases if you respect the rules of electro-etching with metal plate/same metal salt electrolyte, and a low voltage.
• By using electro-etching a workshop can save on the costly investment in a fume extractor hood to protect etchers from harmful gas emissions generated in the traditional etching with acids.
• The electrolytic bite does not produce gas bubbles that can cause the etch to stop. Therefore it is not necessary to watch out for or remove these bubbles as is the case with acid etching. While electricity is etching you can be working at other plates.
• The electrolytic bite does not generate metal wastes that can accumulate in incisions and obstruct the etching process.
• Electrolytic solutions do not become exhausted with successive bites, so it is easier to calculate the time of bite.
• Because the electrolyte does not become exhausted, this makes it a very economical method in contrast to etching with acid, where the acid solution becomes weaker with every use until it is depleted.
• Electrolysis eliminates the problem of depletion completely - I'm still using the same electrolytic solutions that I started working with in 2001!
It is a great time for looking forward in printmaking. With practice I'm sure we will find ways to avoid or remedy any minor issues. It is necessary to give some time to electro-etching, to work with the techniques to research its nuances, to make a virtue out of necessity. I hope this introduction will fire your enthusiasm to give electro-etching a try!
Electro-etching Some Disadvantages
Electro-etching offers a great alternative to etching with acid, but as with everything, it also has some disadvantages:
• You still need to take precautions with the raw sulfates and resulting electrolytic solutions.
• The necessity of protecting yourself with rubber gloves and a dust mask so as not to inhale the sulphate before it has been dissolved and to avoid it coming into contact with the skin and eyes once it has been diluted.
• A feature of electro-etching is that it will bite isolated lines deeper than those that are close together, or cross hatched lines. Also it tends to bite harder in the external areas than at the center of plates (edge-effect). In addition, electrolytic etching bites harder on the edges of wide lines and edges of resists of large areas of open bite. This is more noticeable in prolonged bites. However, all these drawbacks can be compensated for by using a cathode grid in the electro-etching unit instead of a cathode plate.
• Using electricity to etch may be a disadvantage for some etchers, as they do not want to use this energy source which may seem dangerous. However, taking into account that the voltage and amperage used are very low, there is no risk of electric shock if you accidentally touch both electrodes at the same time. In spite of this, you should avoid short circuits caused by defective connections or by accident.
• The fact that it does not use resin dust or asphalt dust limits the possibility of achieving a flat, even tone of different intensities as with traditional aquatint, which we have used for several centuries.
There have been attempts to remedy a number of these drawbacks but there is still some way to go. However, with practice, we will certainly find a way to improve and avoid them.