“Etching, a form of intaglio,whereby The design is cut, scratched, or etched into the printing surface or plate, which can be copper, zinc, aluminum, magnesium, plastics, or even coated paper.” Encyclopedia Britannica
These photos were taken during a workshop by printmaker Frances Luke for the Eurobodalla River of Art Moruya New South Wales. Australia.
Etching is a printmaking technique developed well over 500 years ago. An etching is made by using acid, we used Feccic chloride, ( please wear a mask when using this) or a salt to bite into the surface of a flat metal plate, in our class copper. “The longer the plate bites, the deeper the bite is, and the darker the mark. Most other printmaking techniques, such as relief (linoleum block, woodblock) and silkscreen, only produce one tonal value per plate, but with etching, many values from the lightest grey to the darkest black and many different types of marks can be created on one plate.” http://www.julialuceycom
How to design into copper plates:
We used a combination of hardground (line) etching and aquatint, even though the workshop was really only to be on hard line etching. (Most printers love aquatint because it creates a plate that adds the richness of different grey tones and can create almost a painterly line.)
Bitumen – Hardground:
As the copper plate is oiled lightly, this needs to be cleaned,using 1000 grade wet and dry sandpaper, just moist. and or gumption ( cleaning product.)
To create a hardground line etching, we painted a thin layer of bitumen on to the cleaned copper plate. Heated to distribute evenly.
This is the resist- to stop the acid biting into the copper plate. We used an etching tool/ needle to draw our image, exposing the plate below the hardground.
If you are uncomfortable drawing straight on to your plate, draw your image first on tracing or kitchen paper. Our teacher Francis suggested we use the technique of grinding a conte, sanguine, finely and dusting the back of the paper with the compressed chalk. Rub hard into paper.Tape this to the copper plate so it won’t move. Transfer image with h or hb pencil. Press lightly so as not to remove bitumen.
Stick “Contact ” on back, before immersing in bath, to protect copper plate. Add a small amount of blu -tack to each corner of the plate, this keeps it of the bottom of the bath.
Put the plate in a tray of acid.We used Ferric Chloride to make the lines bite deep.
A 50/ 50 mix of Ferric chloride and demineralised water. Always add ferric chloride to water. Our teacher added two drops of ascorbic acid to reduce the amount of residue.
We left the copper plate in for 20 minutes. ( Tilting bath now and then to check solution washes over plate.moving the residue around.) This can vary as to how deep you want your design lines to bite. Then wash solution off in water. Working outside because of the fumes , we ’tissue d” off the bitumen with turpentine, and some baby oil to remove last of residue. Try not to touch copper as the grease in your fingers will etch into plate.
Now that we have etched the plate we can print it. Firstly we needed to bevel the edges of the plate so that they do not slice through paper (or worse the etching blanket). Use a file and downward pressure. Slide the plate between paper to keep finger prints off plate.
Now we can apply ink. Some use a wide flexible plastic pallet knife, but a cancelled credit card works too, to apply a thin layer of ink over the whole plate.
We used a fabric called tarlatan, a scrim similar to cheese cloth. this arrives full of sizing, which will scratch your plate. So remove by scubbing the material against itself or run it around chair leg. pad up and using the flat surface of pad, softly push the ink into the areas that have been bit with acid. Making circular motions work from the centre to the outside.Be aware that the heat of your hand will warm ink and blur it, so angle plate when you handle it. You are not forcing ink into bite it’s like abolishing motion.
Now that your plate is inked, prepare it for the etching press. The paper we used was Fabriano Rosapina. Some printers soak the paper for at least an hour (depending on the type) in water. Then blot the paper and place each piece when needed over the etching plate. Or the paper can be pre sponged, each sheet, piled and then kept moist by wrapping in plastic.
On the press place your copper plate, design side facing up. Lay your paper over the copper plate. On top of the paper place the wool blanket and then pull the plate through the etching press. “The intense pressure of the steel drum on the press pushes the soft damp paper into the bitten areas of my plate that contain ink and my image is printed.” http://www.julialuceycom
The print can be coloured with ink. As the colour yellow can be thick and tacky, Francis our teacher suggested using oil of Lavender or oil of cloves to dilute the ink.
How many prints would you suggest we take from each etched plate?
Francis suggests taking 50 to 30 prints per edition.
All that was left to do was clean the copper plate with baby oil and wrap in tissue paper to store. I highly recommend you try copper plate etching.