I have been experimenting with copper sulphate etch for some time now etching zinc and aluminium in the same bath and I have had some very pleasing results.
I am currently working on a custom plate for artist Tate Adams and require some further testing before I mix up a large copper sulphate bath for etching aquatints.
It is possible due to the way the copper sulphate and zinc react to create an aquatint tone without using a rosin. To get the desired result, testing is necessary.
A fresh solution creates the best results so I will be mixing up two small solution baths to test for the best results.
How to mix a copper sulphate for a zinc plate aquatint etch.
- Fine line, course aquatint, soft ground: 50 grams of copper sulphate to 1 litre of water (comparable to a nitric acid solution of 7-8%)
- Fine aquatint: 25 grams of copper sulphate to 1 litre of water (comparable to a nitric acid solution of 4-5%)