December 18, 2014 (printed 12/30)
Researchers: Audrey Blood / Jenny Gover
Room Temperature: 65 degrees F
Materials: Future floor wax, Golden airbrush medium, Golden flow release, Akua monotype ink jet black, Golden GAC-100
Abstract: Refining Edinburgh mix to darken color of spray
Edinburgh Mix #3 (plate 13)
10 tsp Future Floor Wax (added last)
1.5 tsp Golden GAC-100
3 drops Golden Flow Release
3 drops Golden Airbrush Medium
4 tsp Akua Jet Black Monotype Ink
We observed last time that the GAC-100 created some small clumps in the mixture when it was added directly to the floor wax. To try to avoid this, we decided to mix the GAC-100, flow release, airbrush medium and Akua monotype ink together first, and add the floor wax last. The mixture was then sprayed through the Badger airbrush on the finest setting onto newsprint. A 4.5″ x 6″ copper plate was sprayed at a distance of 6 to 8 inches with approximately 15 passes. It was set in the drying box for 20 minutes.
The plate was step-etched on 12/18 in 37 degree baume ferric chloride. It was placed in the stripper bath of 3 cups washing soda to 12 liters of warm water for 20 minutes, rinsed, dried, and printed.
This mixture was initially concocted with 3 teaspoons of Akua monotype ink. On close inspection, there are a few grainy clumps of GAC-100 at the bottom of the container, even though the floor wax was added last. It seemed like they were not significant, and were fewer in number than the previous two mixtures. Compared to our first Edinburgh mix, this mixture appeared to be a denser black color due to the increase in Akua. When smeared on paper, however, the tone was still very grey, so we decided to add an additional teaspoon of Akua monotype in for a total of 4 teaspoons. The viscosity after adding the 4th teaspoon was unchanged and still similar to Z-Acryl. The spray from this mixture was fine and even, with a tone dark enough to see on the plate.
The ground came off easily after etching with approximately 10 minutes in the stripper bath.
We printed on a Takach press using 2 sizing catchers at 5.5 pressure. Ink: Charbonnel #55981 oil-based etching ink with 2 drops 00 plate oil. Paper: Hahnemuhle copperplate white. This plate printed well with a fine, even tone.