What is an etching? - Etching on copper plate with acid

SEE MY WORK ALSO AT:

ARTISTS ONLINE

PAINTINGS AND PRINTS

ARTISTPORTFOLIO.NET

ETCHINGS: Rye Beachscapes

WHAT IS AN ETCHING? PROCESS AND TECHNIQUES EXPLAINED

Hard Ground, Soft Ground, Copper Plates and acid. Press, paper and proofs.

Watchbell Street:

Plate before biting

When the plate is immersed into acid* the exposed areas are bitten and when the wax is removed the drawn image is revealed as having been “etched” into the plate. The plate can then be inked up with ink being driven into the etched lines. The plate is then wiped in order to remove the ink from the surface. A sheet of dampened paper is placed over the inked plate and both are rolled through a press under high pressure The rolling action and the pressure cause the ink to be squeezed out and sucked out on to the paper. The resulting image is characterised by extremely fine line and subtle tones.

Successive biting to different depths can be precisely controlled with experience to create an infinite number of tonal variations.

*I use Dutch mordant: which is composed as follows: Hydrochloric, 200 grammes; chlorate of potash, 20 grammes; water, 880 grammes. This acid works slowly and evenly without undercutting the lines and without losing its strength as it bites. Nitric acid is more vigorous, but can cause deep lines to merge

Soft Ground

A copper plate is covered thinly with soft-ground; a non drying wax which is resistant to acid. Any textured object pressed onto the wax will pull the wax off when removed and leave an approximation of its texture. Placing paper over the plate and drawing on it will therefore create textures echoing pencil marks and some degree of “shading” can be achieved. The plate can then be immersed in acid and bitten and then printed.

The etchings here use a combination of hard and soft ground. The image is initially drawn out using a pencil and paper over the plate to give a soft tonal “sketch”. After biting the plate is covered with hard ground and the lines and tones are deepened and texture and detail added.

Sticks and Stones:

Plate before biting

Sticks and Stones:

First print off plate

Sticks and Stones:

Final state

What is an etching? Techniques explained

WATCHBELL STREET, RYE - Rye limited edition etching by Colin Bailey

Etching is a form of printing that along with engraving comes under the category of Intaglio. Images produced by this process are the result of ink being forced out of the incised lines in a zinc or copper plate using a heavy press. This results in slightly raised ink on the paper and a characteristic plate mark showing the edges of the plate

Others categories are:

Relief:

The image is printed from the raised areas with non printed areas cut away - woodcut

Planographic:

The image is printed from the same surface as the non printed areas - Lithography

Stencil:

The image is printed by ink passing through areas cut away from a stencil - Serigraphy, better known as screen-printing or silkscreen

Ink jet:

The most recent development, ink is sprayed onto the printing surface. The most basic example being the standard home printer and the commercial application being the high end giclee printer. What is a giclée print?

History

The techniques of etching and engraving are believed to have originated in Medieval times as a means of decorating armour and metal. The incised lines would have often been filled to darken them and from this it would have been a short step to transferring the image to cloth or paper. One suggestion is knights falling on soft ground would have left an impression of the patterns on their armour.

Etching differs from engraving mainly in that acid does the work of removing the metal. This allows a fluidity of mark and in the hands of an expert a almost infinite degree of control; The depth of each line can be controlled by the acid and so can hold as much or as little ink as is required to achieve the desired tone. Most metals can be used for the etching plate although the most common are Zinc and copper. Zinc is often used as a starter metal for students as it is relatively cheap and easy to work. Copper is much denser and less “brittle” and will yield more prints. It can also be steel-faced to last almost indefinitely.

The two etching techniques I employ are Hard Ground (the most basic form of etching) and Soft Ground. I rarely use aquatint- a process I will nevertheless explain later. The techniques I describe here are traditional methods adapted and modified to a modern domestic environment. Virtually everything apart from the printing can be done at home with suitable care and little space. The Modern table top press is now capable of printing etchings that match those done on heavy studio press (at least for small plates) and so there is now no reason why even the printing cannot be done at home!

Preparing the plate

I use 16 gauge copper plate (1/16th inch) which comes in 500mm x 1000mm sheets polished on one side and covered with a plastic protective sheet. This I cut up (very carefully!) by scoring into it over 50 times with a heavy craft knife and then snapping it away. This may sound a little brutal but I have not had a lot of luck with guillotined plates - however sharp the blade there nearly always seems to be a slight bending or compression of the metal which is almost impossible to straighten and which causes the prints to fade away at that edge. Most of us don’t have a heavy duty guillotine lying around the house and trusting this to others can result in scratches and plates that vary in size and are not perfectly square. I have experimented with three plate colour etchings in the past and this can make the plates difficult to register. Before removing the plastic coating I roughly bevel the edges of the plate to a 45° angle using a coarse file. This is optional but I find it much easier to roll the plate - with less chance of the roller catching the edge. When the print is finally ready to edition I finish off this bevelling with fine sandpaper and polish it up with the back of a spoon which gives a sharp clean print mark that does not cut the paper. Bevelling the plate before printing is compulsory in any class I teach! I have seen too many expensive blankets sliced through by the edge of an un bevelled plate

After removing the plastic coating I clean the adhesive residue off with white spirit and check for scratches. If the copper plate has tarnished I polish it with Brasso.

Before laying the ground on I degrease the plate. Traditionally this would have been ammonia and chalk but in a domestic situation washing powder works as a substitute (be careful of the particularly gritty ones!). Cream cleaners such as Jif (Now unfortunately renamed Cif!) used to be perfect as they contained ammonia but in our health and safety conscious times this has been changed and they just don’t work as well.

For heating the plate I use an ordinary domestic cooker (Gas is better, but with a bit of practice an electric ring is just as good. Manoeuvre the plate with a metal spatula so it is heated evenly and place it on a flat smooth heat resistant surface (this will get ground on it so check it can be cleaned with white spirit!)

Hard Ground

If you have used the roller recently and it has been kept wrapped in a plastic bag you will probably have enough ground already on the roller. Otherwise draw on the hot plate with the ball of hard ground - about enough to sign your initials 1 inch high is usually enough for medium size plate. The ball should skid across the plate without dragging. Roll the ground until it is even and the plate looks as though it has been coated with golden syrup (thicker than this and it will chip or make finer lines bite unevenly. You may well need to re-heat and re-roll the plate several times. Use the roller in a swooping motion in one direction to pick up the ground, and backwards and forwards to load more ground on to the plate. As the ground cools it will become sticky and hard to keep even. When reheating the plate be careful to remove it just as the ground starts smoking as further heating will cause the ground to scorch and become porous to the acid.

Obviously having a ground the colour of Golden syrup an a copper plate is not going to be that easy to draw on! The ground will be a matt non reflective finish when cooled and the copper will be shiny but I would still advise smoking the plate.

Smoking the plate

This involves clamping the plate on one edge with a pair of swan necked adjustable pliers (protect the surface of the plate with a small piece of folded card) and holding it above your head with the grounded surface facing down. This should be done before the plate has cooled entirely. Gently smoke the ground with a burning bundle of tapers (about 10 bound spirally from the bottom with masking tape) so that the carbon softens the wax and is absorbed into it. Start further away from the plate and as the ground starts appearing shiny brush the tip of the flame (about an inch above the visible flame) across the plate in a systematic pattern. This will take a bit of practice but the plate should cool to a uniform semi mat finish. I harden the wax at this point by running it under a cold tap. Any powdery carbon on the surface can be gently rubbed away with an orange polishing duster. Examine carefully for any specks of copper showing through as THESE WILL BE BITTEN!

The surface can now be drawn on using a variety of instruments. I have used an old dart with a pencil screwed into the barrel and presently use a sewing needle threaded through a propelling pencil instead of leads!

Please see also:

Giclée explained

Ryepress print blog

Return to top of page

LIMITED EDITION PRINTS INFORMATION

Colin Bailey

ARTIST & PRINTMAKER