Etching with copper sulphate

I recently attended a two day etching workshop at the Wrexham Regional Print Centre - www.regionalprintcentre.co.uk, tutored by Tracy Hill - www.tracyhill.co.uk.

I have limited experience of acid etching, and was interested in experiencing a less toxic method. The process is the same as the traditional acid method but obviously different chemicals are used.  We used both zinc and aluminium plates as matrices and printed with oil inks onto Hannemuhle and Somerset paper.

Tracey demonstrated every stage which was useful for everyone whatever their previous experience, and she was very relaxed and generous when asked to go over the details again for anyone who needed it.

Firstly the edges of the plates had to be bevelled, to prevent the blankets on the press being damaged but this also means that the final print will be cleaner, and then degreased as grease, including that from fingers, would effect the ground that was to be laid over the plate.

The acrylic ground a mixture of two substances - rather than a traditional wax ground - was then rolled on to the chosen plate. Textures were created by laying various found objects, lace, feathers, net, dried plant material,string, stencils, onto the plate which was put through the press. The plate was then heated on a hot plate to fix the ground and finally placed into the copper sulphate solution.  The solution etches into the areas of metal which have been left exposed by the textures pressed into it. The plate is then cleaned of the remaining ground and detritus from the mordant and printed.  This is my first attempt - two feathers and a piece of unravelling cord on a zinc plate.

Before printing I used a dry point needle to emphasise some of the details of the cord that and also add details of a third feather in the upper left corner to link in with a pale mark that looked like a quill. Ideas for future development includes printing with chine colle to emphasise the feather structures, burnishing the highlights and more dry point work.

I next tried a smaller zinc plate - the same process with the ground but after allowing it to partially dry for a few minutes I added water with a brush. The result is reticulation where the ground - which is water based - partially dissolves with the added water and produces interesting, not entirely predictable results.   Again before printing I added dry point - too faintly as can be seen in the prints but these can be worked on further.

I burnished the un-etched metal of the plate to make the highlights more prominent added a traditional wax hard ground and emphasised some of the dry point marks made earlier and then inked in green as an experiment.  I don't think the colour works and prefer the blue black - the abstract design reminds me of the flint walls of West Dean and in the future I will continue to work on this plate to emphasise this element and perhaps try to replicate the lovely colours one sees in flint particularly when wet.

The next day I worked with aluminium plates.  These are slightly less predictable in the mordant and I decided to try with some semi abstract landscapes. I have had a week drawing mountains recently and these were in the forefront of my mind as inspiration.  The first plate was covered with the ground and then water added for the reticulation.  The abstract shapes reminded me of clouds so the mountain range was added below with a dry point needle and some more water added to provide texture on the land.  The second plate was a thin strip.  I drew onto the ground using a dry point needle for an impression  of landscape and also added a little water reticulation for tone and texture.  On reflection, this was too much for such a small plate - less is more in this instance.  After heating the plates to set the ground, they were put into a saline copper sulphate solution.   The back of the plates had to be covered with plastic tape to prevent the back being attacked by the etch and in that process I must have scratched the larger plate with a small piece of grit. This didn't become apparent until after the print was pulled but as can be seen left quite a prominent series of marks all across the plate.

I inked the plate again trying to remove some ink from the most prominent mark but this seemed to make it more obvious, so decide to add to the scoring with dry point - in an attempt to make a virtue from an error  - and extend some of the marks including the very harsh ones to create a feeling of wind sweeping over the landscape.  This was an improvement and when I inked the landscape in green making it more prominent it made the image more balanced still.  The motto is - make sure the area is perfectly clean before turning the plate over before taping the back!

Finally I decided to try the small landscape with some chine colle - a white tissue with tracings of green ink on it.  The plate is too small for the large piece of tissue so I will print the plate again with smaller additions perhaps in unrealistic colours to emphasise the abstract nature of the marks and to de-emphasise the complicated, detailed landscape I tried to represent.

All in all a very busy two days - lots of experiments and 4 plates that I can continue to work on and develop at home and perhaps take  back to Wrexham for some more etching. I have lots of ideas and intend to play around and see how far I can push them.