Etching Zinc with Copper Sulfate Mordant Test 3

Test Summary
This test seeks to determine an ideal etching time for a line drawing in a hardground. it also attempts to determine at what point the Copper Sulfate compromises the ground and creates foul biting.

Date: February 18, 2011
Researcher’s Name: 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. I rolled BIG on the edges of the plate and applied Z-Acryl stop out solution to any areas that I might have missed with the ground. I dried BIG in the hotbox for 25 minutes or until it was smooth to the touch without any tack. I used an etching scribe and roulette to create crosshatching in the background. I added some stippling on the tree trunks in the foreground.

Melissa's Grounded Plate

Melissa’s Grounded Plate

Melissa's Plate with Stop Out

Melissa’s Plate with Stop Out

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

Timed Application of Mordant
Every three minutes I removed the plate from the mordant and placed it in a bath of warm at room temperature. In the printed proof below I marked the time increments on the side of the print. Following the first 3 minutes I rubbed the ground with my hand and it chipped in the middle of the plate. After that I exclusively used the sponge to wipe away any zinc debris in the etched lines. I applied Z-Acryl stop out solution to areas that I no longer wanted to etch. The stop out air dried for 20 minutes and I placed the copper plate back in the mordant bath. After 12 minutes the lines started to under-bite. The total etch time was 12 minutes.

Removal of Grounds
The ground was removed using the paint stripper Eco Strip by Homestrip. Eco Strip comes as a gel and is an excellent substitution for the stripper bath. I rubbed the Eco Strip on with a rag and the ground comes off easily. Any stubborn areas are scrubbed with a non abrasive toothbrush and finished with simple green and a rag.

After Bath Evaluation
The edges of the plate did not etch and there are no signs of foul biting.

Melissa's Exposed Plate

Melissa’s Exposed Plate

Inking Methods
The plates was 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: Hahnemuhle Copperplate
Paper Soaking Time: 15 Minutes
Press Blanket Setup: Sizing catcher and pusher, 10.2 pressure, Small Takach Press

Test Conclusion
The lines etched well and they retained a needle point sharpness.

Printed Images

Melissa's Print

Melissa’s Print

Etching Zinc with Copper Sulfate Mordant Test 4 >