Continuing my experiments with different mixtures of acrylic-based resists, I'm getting some idea about which combinations of materials work best in order to print a good image, and to get a clean plate surface around the lines. All of the prints below were taken from re-used 6" x 4" copper plates. The inks are Akua intaglio inks.
The following plate had three layers of dried resists made from GAC 200 and a few drops of black airbrush ink. The lines were drawn into the dried resist using an etching needle. The print looks remarkably like a hard ground etching, even though no mordant was involved. It's difficult to avoid air bubbles in the GAC 200, though, but I decided to let those stand as part of the texture of the print:
The next plate is the same mixture, the drawing was done with varying pressure of the etching needle, so that part of it looks like en etching, parts of it like a drypoint. Some of the resist dried in tiny ridges that picked up ink in the background. It took a lot of wiping with q-tips to make it look white:
The next one is a resist of GAC 200 and a little water to thin it before pouring onto the plate. Once it was dry, I prepared a small amount of GAC 200 and half a teaspoon of fine carborundum and drew the figure of the boxer. I drew the lines with an etching needle. I inked the plate à la poupée, using blue-black for the figure and red for the drypoint. Again, I let the ink-trapping air bubbles in the resist become part of the background for the print:
Lastly, this plate was coated with two layers of Lascaux acrylic resist. It's more expensive than GAC 200, but you get what you pay for: it dries very quickly, with much fewer air bubbles (which I am sure I can eliminate completely). I also used the Lascaux with carborundum for the collagraph figure, and it made a very dark tone even though I added a smaller amount of carborundum to the mixture.
Next stage: experiment with different strengths of the Lascaux/carborundum mixture to see if it approximates different tones of aquatint.