The thing about using acrylic based/non-toxic products for etching is that it has to accomplish a number of things:
* Degrease the plate.
* Supply a coating (hard ground, soft ground, aquatint) that will resist the mordant and which you can work into and make marks easily.
* Strips off the plate easily so you can print it or work with other techniques on it.
So far, I've got the degreasing part in hand (soy sauce and water, followed by a paste of bon ami and water), the resists mostly in hand (Pledge floor wax for a hard ground, Speedball screen filler for aquatint, stop out made from GAC200 + acrylic paint), and the stripping solution doing ok (soda ash in warm water).
The resists are still the trickiest part. I'm still testing how to apply them properly, how long you can make marks in them before they harden, how long you should etch them. But with the copper plate shown in the photo above, it looks like things might be converging on a usable set of procedures. The bright areas were protected by the acrylic stop-out. The dark areas are an aquatint created using the acrylic spray with an airbrush. The lines in the stopped out areas were created by stripping off the aquatint, then reapplying the Pledge hard ground, and re-etching the plate. When I print it tomorrow, I should be able to see: a) whether the resists etched properly; whether the reapplied hard ground protected the aquatint from further etching; whether the stripping solution removed the resists entirely.
From the look of the plate, though, I'm hopeful that it will produce a good proof.
This is my studio blog. I also have another blog, Praeterita, which contains more general art-related posts.