Etching Zinc with Copper Sulfate Mordant Test 4

Test Summary
This test seeks to determine the range of faintest to the darkest etched hardground lines within a 14 minute time period. The zinc plate will be stage bitten in 2 minute intervals.

Date: March 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 used Z-Acryl Stop Out solution for the edges and any areas I might have missed when rolling 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 to create crosshatching in the drying rack and a roulette to create tone in the lower portion of the background.

Melissa's Grounded Plate

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. I etched the plate vertically for the first time in a plastic file bin. I used a plastic letter holder that fit into the file slots to keep the zinc plate in place during etching.

Timed Application of Mordant
Every two minutes I removed the plate from the mordant and placed it in a bath of water at room temperature. In the printed proof below we marked the time increments on the side of the print. 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 14 minutes the lines still looked strong with no signs of false biting.

Removal of Grounds
I used Soy Solve and it took a long time to remove the ground. It was especially difficult in areas where Z-Acryl was built up during the stop etching.

After Bath Evaluation
I noticed a cloudy scum floating on the surface of the mordant. It did not effect the quality of the etch.

Melissa's Exposed Plate

Melissa’s Exposed 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: Hahnemuhle Copperplate
Paper Soaking Time: 15 Minutes
Press Blanket Setup: Sizing catcher and pusher, 10.2 pressure, Small Takach Press

Test Conclusion
There was an unintended mark in the left center of the print possibly from a bubble that formed in the Z-Acryl. I noticed that the lines do get marginally thicker as the etching time progresses but not in a negative way.

Printed Images

Melissa's Printed Proof

Melissa’s Printed Proof

Etching Zinc with Copper Sulfate Mordant Test 5 >