October 21, 2014 (printed 10/28)
Researchers: Audrey Blood / Jenny Gover
Room Temperature: 65 degrees F
Materials: Golden GAC-100, Akua monotype ink Jet Black, Golden airbrush medium, water
Abstract: Attempting a spray aquatint mixture using Golden GAC-100 (Part 2)
GAC-100 Mix #2 (plate 5):
0.5 oz GAC-100
0.25 oz Akua jet black monotype ink
0.25 oz Water
3 drops Golden airbrush medium
We mixed ingredients together in small container and sprayed through Badger Airbrush on finest possible setting onto newsprint. The plate was sprayed at a distance of 6-8 inches with approximately 15 passes. It was set to dry in the drying box for 20 minutes, then removed and sat grounded in our drawer for one week before etching. It was then step-etched in 39 degree baume ferric chloride. The plate was stripped first with the stripper solution and finished with SoySolv II spray. It was then printed three times.
spraying Mix 2 onto plate 5
It was difficult to see whether the GAC-100 mixed in thoroughly with the other ingredients. The Akua ink was much darker than the india ink from previous mixtures, so less was needed. The mixture had a similar viscosity to Z-Acryl. We sprayed this mixture onto newsprint, expecting to see a finer spray than that of the GAC-100 and india ink mixture because this had been the case with the Speedball mixes. While the mixture gave a somewhat finer spray, it was not nearly as fine as example sprays of either Z-Acryl or our previous Speedball mixtures.
mix 2 sprayed onto plate 5
The ground was very difficult to strip. We left the plate in the stripper bath for one hour, but this did not entirely remove the ground. Most of the ground was removed by rubbing the plate under running water with fingers. After deoxidizing, we realized that some ground was still left on the plate and used SoySolv II to remove the remainder.
Mix 2 on plate 5 after an hour in the stripper solution for 1 hour
We printed on a Takach press using 2 sizing catchers at 5.5 pressure. Ink: Chabonnel #55985 oil-based etching ink with 2 drops 00 plate oil. Paper: Hahnemuhle copperplate white. The prints appeared coarser than those made from the Speedball mixtures. This plate may have been over-sprayed. The coarse texture of the printed aquatint indicated that too much of the plate’s surface area may have been covered by the spray.
printing plate 5
Akua vs. India Ink as a colorant
After printing plates 4 and 5, we made some observations on the differences between the mixes and the quality of their sprays. When spraying plate 5, there was a large variation in dot size coming out of the airbrush. Smaller dots were being sprayed onto the plate, but were difficult to see, which we thought could lead to over-spraying. We thought this might be because the GAC-100 did not integrate well with the Akua Monotype ink.
We then went back and looked at some of our old mixtures with Speedball screen filler (Experiments #1 & #2) to see whether they had remained emulsified or separated after sitting for several weeks. All of the mixtures with india ink had coagulated into clumps. This didn’t surprise us with the Speedball screen filler mixtures, because of our previous experiments. What we did find however, was that the Speedball screen filler mixture with no colorant had also coagulated. The only mixture that did not coagulate at all was the mixture with Speedball screen filler and Akua monotype ink as a colorant. This led us to wonder whether the Akua monotype ink, which is gum arabic-based, was acting as a suspender and keeping all of the ingredients loose.