This is about etching metal plates with nitric acid
Etchings on metal is an outgrowth of the printing industry where these etched metal plates are used directly in a printing press. In this process ink is applied to the etching then it is printed on a suitable paper or other media. Etched metal plates are also used on their own as an artform. In this case the metal etching is mounted and framed. It is then displayed as a work of art.
Making a metal etching depends on your artistic ability to draw well. It also draws on your ability to handle chemicals because you have to use a dilute solution of nitric acid to do the physical etching of the metal.
The first thing you have to do is pick out a piece of metal to etch. Art and craft stores often stock the metal, if they don't the necessary metal sheets can be bought at a metal supply house. The most common metal that is used for etching is copper followed by aluminum. These are the easiest metals to etch.
To prepare the metal for etching you have to cover the face of the metal with a thin layer of wax. The best kind of wax is bees wax although paraffin will work as well. After this thin layer of wax has hardened it is time to start making the master for the etching. This is done with a sharp pointed stylus that is capable of cutting through the wax layer. You might want to have several different sizes of pointed stylus's available for different sized lines.
When you have completed drawing your picture on the wax using the stylus's you are now ready to etch the pattern into the metal. This is done with a dilute solution of nitric acid, 10% nitric acid will work.
Before doing the etching process you should surround the piece of metal with some masking tape so the edge of the tape sticks up above the surface of the metal slightly to contain the etching solution on the surface of the plate. Cover the surface of the waxed metal with the solution of nitric acid with a brush and allow it to set on the surface. The longer the acid solution is in contact the deeper the etching.
Before you do a completed etching it is best if you make some small test etchings first using the same techniques used as above. You might want to try several different times on your samples before going on to a full etching.
You can make a sample plate by coating a sheet of metal with wax then draw several parallel lines on it with a stylus. Then you can apply nitric acid solution to one line at a time in this way you can observe how much time will produce the desired results.
Your etching process is complete and you can wash of the nitric acid solution by flooding it with water. The wax can be removed with hot water leaving a finished etching. This can be left as is, or can actually used for printing on paper in an etching press available at better art supply stores.
Either metal or paper etchings are works of art that are capable of being mounted and framed. Mounting is when you put your artwork inside a cardboard frame that is larger then the art. The art is enclosed in an opening in the cardboard. Standard sizes of mounts can be bought at art supply stores.
Try a sample first
Wear rubber gloves when working with nitric acid solution it leaves bad burns on exposed skin.