Copperplate Etching

Copperplate image1It’s all about attention to detail and process— things scientific illustrators thrive on. How could I not be entranced with copperplate etching? But beyond the detail, there is so much more. For all the attentive control that one can impose on the copper, there are variables created by acid, paper, ink, and press that allow surprises both discouraging and rewarding, and each print pulled off the press is a remarkable experience. There is a tactile pleasure to working on copper, and there is the added appeal that comes from being able to rework a plate with more marks and more techniques, and results planned and unplanned enhance the art and satisfy the artist. A fortuitous encounter with a master printmaker provided me with an introduction to the medium and I was hooked as soon as I pulled my first crude print. A few years later two women opened a small print studio in my town. I rent time there, bringing my own paper, copper, and ink, while sharing chemicals, solvents and a printing press in a well-lit ventilated space. Several of us occasional printmakers interact there, learning from, inspiring, and teaching one another.

Creating a print is a labor-intensive process involving many stages, beginning with a sketch. I plan my composition carefully, choosing an image (usually a plant) that I feel intimately connected to and will be content to look at over and over again. My design needs to fit within the confines of a piece of copper and must allow for the fact that the image will be reversed when printed.

Distinct from creating the design, preparing a plate follows several steps that demand specific attention. Edges of the copper plates, whether purchased in pre-cut sizes or cut to size, need to be ground with a belt sander or filed to a 45-degree angle. Unpolished copper needs to be buffed with super fine steel wool, wet/dry sandpaper (up to 1500 grit) and polishing compound. Then the plate is de-greased and coated with a thin layer of acid-resistant ground (a waxy mixture of asphaltum and solvent) which dries in a few hours to a hard surface. The sketch is then transferred with blue Saral paper onto the prepared copper.

I use a steel etching needle to make marks, cutting firmly enough through the ground to expose the copper but gently enough to not cut into the copper. The marks are similar to pen and ink work, with stipples, cross-hatching and parallel lines used to achieve texture and a range of tones, but the scratching and gliding of the needle feels very different from drawing on paper. With little resistance from the ground, there is less control which is a bit liberating, but the needle can make finer lines than any pen nib so there is potential for a great deal of detail. I often work directly under my dissecting microscope to make the finest marks. I err on the side of too few marks, both accidentally and intentionally, and usually need to rework the plate to add more marks to intensify lines and create darker tones.

After the image is scratched into the ground, the plate is submerged in a bath of ferric chloride which ‘bites‘ into the marks in the ground. The amount of time in the acid determines the depth of each mark, anywhere from 30 seconds for an aquatint to 45 minutes for line etching. Once the plate is etched, the ground is removed with solvent and the plate is ready to be printed. Oil-based ink is mixed with plate oil to achieve a desired tone and consistency and then densely applied to a warmed plate. Then most of the ink is removed, which for me is the most enjoyable part of the process. It involves wiping with ‘tarletan‘, a rag that resembles starched cheesecloth, wadded into a fist-sized ball. The gentle yet firm motion pushes the ink into the etched marks as it simultaneously removes it from the surface of the plate. As the ink is removed the lines become revealed and the copper takes on a delicate sheen. Final wiping is done with the heel of your hand. Removing more or less ink allows for ‘plate tone’ which is but one of many variables that affect each print. Characteristics of the ink, type of paper and pressure of the press affect each print and achieving consistency throughout an edition takes practice as well as trial and error. One must also keep in mind that printmaking is a very messy process for many steps but it requires you to be absolutely neat and clean for other steps, especially when handling paper, and much hand washing occurs. When a plate is ready to print, it is placed on the press facing up.

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Paper, torn to size, is soaked in a bath of water, blotted dry, and laid on top of the plate, felt blankets are then placed over the table of the press, and the press is turned with suitable pressure until the print has moved through. The blankets are then lifted and you peel off your print. So many steps, carefully considered and adhered to, and yet the final result is always a surprise. What took hours and perhaps days of preparation will invariably yield an exclamation, be it pleasurable satisfaction that leads to the decision to re-ink and pull more prints and create an edition, or resignation to rework the plate and hope for better results. If all goes well you carry your beautifully and flawlessly executed print into the sunset. Otherwise, you analyze the problems. An inferior print may result from easily modified variables—over-wiping or too little wiping, paper too wet or too dry, ink too thick or too thin, press pressure too hard or too light. If the print has marks that are not etched deeply enough, or if you want to add more marks and modify your drawing, the process of degreasing and re-coating the plate with ground and working the plate is repeated. Unintentional marks (‘foul bite’) can be scraped and polished to remove or lessen the effect to some degree, or appreciated for the character they add. Choice of paper adds to the mix. Rives BFK, German Etching, Magnini Pescia and Hahnemuhle Copperplate, with color ranges as simple as bright white to cream, provide distinctive textures and qualities. There are other techniques to explore, including aquatint which involves adding a fine layer of rosin dust and selectively stopping out areas to add a range of tones, soft ground which allows marks similar to crayon marks, chine collé which impresses transparent colored paper onto the print, and hand coloring of prints with watercolor or thin layers of acrylic paint. So much to learn, so much to experiment with. A review of a recent exhibit of contemporary prints ran the headline ‘The Enduring Allure of Scratching on Metal’. Looking at old etchings or trying your hand at creating new ones will demonstrate why copper etching has endured for over 500 years.

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Notes and Acknowledgements

This article appeared in the April 2011 GNSI newsletter.

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