Etching Zinc with Copper Sulfate Mordant Test 1

Test Summary
We are testing the effectiveness of BIG (Baldwin Intaglio Ground) hardground in our Copper Sulfate mordant.

Date: February 11, 2011
Researcher’s Name: Chelsea Mullins and Melissa Mandel
Plate Material: .040 Zinc
Plate Size: 5 in x 7 in

Plate Preparation
The plate was degreased with soy sauce that was rubbed onto the zinc plate using a piece of rolled felt, rinsed and then dried with a clean rag and blow dryer. The BIG was squeezed from the tube onto a clean, glass inking slab, spread with a knife and rolled up using a 4″ diameter, medium hardness brayer. Several thin layers of red BIG were rolled across the surface of the zinc plate, building gradually to the point that the zinc did not sparkle through the ground. We dried BIG in the hotbox for 25 minutes or until it was smooth to the touch without any tack. Using etching scribes and a roulette we drew through the ground and completed our image. The drawn lines were originally needle thin. Red sharpie permanent marker was used to stop-out the edges of the plate.

Chelsea and Melissa's Grounded Plate

Chelsea and Melissa’s Grounded Plate

Etching Notes
The Copper Sulfate Mordant consists of 50gm salt + 50 gm copper sulphate + 1 liter H20 stored in a plastic lidded container. We created a shallow bath in a plastic tray where we can place the zinc plate for etching.

Copper plate in the Copper Sulfate Mordant

Copper plate in the Copper Sulfate Mordant

Timed Application of Mordant
After 1 minute 30 seconds the sharpie areas started to etch. 7 minutes 30 seconds ground is holding up well as we use a sponge to wipe away zinc debris out of the etched lines. 10 minutes 20 seconds the lines begin widening. 15 minutes the lines are much wider. 18 minutes we can feel the edges of the etch with our sponge. 20 minutes foul biting and larger spots are loosing detail in roulette areas.

Removal of Grounds
We used DeSolve to remove the BIG ground but the smell is too strong.

After Bath Evaluation
The plate looks over etched.

Chelsea and Melissa's Etched Plate

Chelsea and Melissa’s Etched Plate

Etch Detail

Etch Detail

Chelsea and Melissa's Plate

Chelsea and Melissa’s Plate

Inking Methods
The plates were inked with unmodified Graphic Chemical & Ink Co. Bone Black Etching Ink #514. The ink was carded on with mat board scraps, wiped with used tarlatan, and then palm wiped.

Paper Type: Hahnemule Copperplate
Paper Soaking Time: 15 Minutes
Press Blanket Setup: Sizing catcher and pusher, 10.2 pressure, Small Takach Press

Test Conclusion
We lost detail in the roulette areas and foul biting created a texture in the background. All lines are wider than originally desired.

Printed Images

Chelsea and Melissa's Print

Chelsea and Melissa’s Print

Etching Zinc with Copper Sulfate Mordant Test 2 >