On the latest project entitled the Riverman, Lisa Kane put an insane amount of work into her etchings. I don't think most people realize how much time and effort go into each one, so I thought it would be a good idea for Lisa to break it down for everybody out there.
I use copper plates but also zinc and aluminium can be used. Copper is more expensive but the images come out better. Start with a polished copper plate free of any grease by cleaning it with ammonia and chalk powder. This is essential so that the next stage, when the resin is applied, you'll get an even 'bite' when the plate goes into the acid.
There are two drawing technique used. Hard and soft etching. Hard etching is for a clean fine line and is made by applying a hard etching ball, a resin that is melted onto the heated copper plate then rolled evenly. The same technique is used for soft etching. The difference between the two is that once the resin has dried, the hard etching plate is drawn on directly with a needle type tool. Soft etching is a more sketchy line that is made by laying a sheet of tracing paper over the plate and drawing the image with a pencil so when the paper is lifted, the image appears in the resin.
Once the image is drawn, the other side of the plate is painted with a varnish to protect it from getting worn away in the acid. The acid...or ferric chloride, is put into a deep tray and the plates are immersed. It takes a good 20 minutes for a hard etched image to develop, shorter times for soft etching. The term 'bite' is used for when it's in the acid. Once they are ready, they are run under water to stop the bite. The acid bites away any line drawn on the plate that is exposed to acid. The resin stops the acid biting. Take off the resin and you have the image ready to print.
Aquatint is the next stage that gives tone to the plate. A fine dust is spread evenly on the plate. I use a kind of acrylic liquid applied with an air brush. The plate is cleaned again from grease and any areas of the image I want to be white are painted with a varnish to stop the acid biting. The plate is put back into the acid, timed, usually the times are much shorter for the acid to bite an aquatint. I usually count to ten then the plate is taken back out and immersed in water. This is repeated until you have varied tones on the plate.
Etching ink is spread onto the finished plates with a piece of card then a piece of scrim is used to push the ink into the bitten lines. To finish, tissue paper takes off the ink on the polished parts of the plate to give the image contrast. The inked up plate is then put onto a etching press. Special paper is soaked in water, taken out and blotted then placed onto the plate, covered with felt blankets and rolled through the press. The damp etchings are then placed between drying boards to dry flat.