Water & spit biting
We prepared a dedicated work area for this because the process can be quite hazardous as it involves pure nitric acid and keeping that contained is all important. It is a colourless liquid and is, obviously, highly corrosive.
The studio has several dedicated fume removal areas with pull-down front perspex to protect users, and we set up in one of those. Using a very large, heavy plastic tray as my work area I arranged three containers within it: pure nitric acid, water and hand wash detergent.
The print plate was laid over base struts so that excess liquid could run off.
Water was tipped onto the plate. Normally it would immediately turn into small droplets but with the aquatint base it appears to cover the entire area where it is applied. See my previous post to understand why this pooling occurs. Nitric acid, from the jug, was then brushed in selected areas over the water.
Note: I’m well aware of safety issues and that gloves should always be worn, but I guess it is the teacher’s prerogative whether he chooses to wear them or not.
Above you can clearly see where the acid has turned cloudy in the water. The idea is to move it around, alternating diluting and adding acid. Where the acid sits for differing lengths of time determines the depth of the etching that occurs. So this technique is perfect for creating smooth tonal differences across a surface. By keeping the plate wet (in this case only the sky down to the horizon line) the acid is suspended and can be lightly moved around, so avoiding harsh outlines of etched areas.
This soft process should give excellent sky tonal value without vastly bitten areas.
I’m told that in the olden days (I’ll let you research exactly when that was yourselves) spit was actually used as a resist against acid biting. However, my tutor usually uses washing up liquid. Not having any to hand I took a container and purloined some hand-wash from the closest bathroom.
On the left, hand-wash is being dribbled in lines across the lower half of the plate, in the hope that we get some water movement in the final prints. On the right a light amount of water has been added in the remaining areas. The hand-wash will act as a resist against the acid but the edges of it will gradually mix with the water. Once the acid is added and the hand-wash is moved around marginally it should be possible to achieve some quite dynamic changes in tonal value as the acid bites in very selected areas.
On the left, the acid is being added. This isn’t being softly brushed across as per the sky, here it is being applied carefully in horizontal lines. It is filling in some of the spaces, mixing with the water, forming waves and movement and the hand-wash is being reshaped to stop out the acid in some places.
On the right, the plate is almost finished etching and is ready to be plunged into a water bath to remove the acid and hand-wash. You can see the difference between the soft approach in the upper sky area and the more robust effects on the lower section.
Ready to print.
With only 20 minutes of class time left and quite a lot to still clear up I only had time for one initial print. One of my classmates kindly told me to use the colours she had already mixed as there was no time to start from scratch. The colours were lovely but a bit too concentrated for my design as I’m keen to try a heavily diluted background and have the swan sitting brilliantly in the foreground.
Still, beggars can’t be choosers and I was grateful for the offer to use her inks. So here is the first print proof of this single plate.
OK, a bit of work still to do here to get this happening how I want to see it, and I have yet to print the soft ground etched plants as a second layer.