When large areas of a metal plate are etched out (see below Etching), leaving the design in relief to be surface printed, the process is generally called relief etching. Usually the method is used for areas, but it can be also used for lines. The English artist and poet William Blake was the first printmaker to experiment extensively with relief etching. He devised a method of transferring his handwritten poems, together with the illustrations, onto the metal plate to be etched.
In contemporary printmaking, relief etching is used extensively for colour printing. The different levels of the plate can be inked with different colours. Relief etching is also a popular method of making inkless intaglio prints (shallow bas-reliefs on paper). Rubbing
Simply by placing a fine paper over an incised or carved surface and rubbing the paper with heelball (wax and carbon black) or daubing it with special ink, an artist can use practically any surface for printing—including, as in Japan, the body of a fish. Rubbings were probably the earliest prints made by man. In India rubbings were made of tombstones and temple bas-reliefs, and in China rubbings were used to reproduce calligraphy as early as the 2nd century ad. In addition to fish rubbings, the Japanese made rubbings of metal ornaments.
Today many museums sell rubbings of bas-reliefs in their collections. In the United States rubbings often are made of colonial and early 19th-century gravestones, and in Europe they are applied to brass plaques mounted in stone slabs. Dotted print (criblé)
A traditional technique of the goldsmith long before engraving for printing purposes was developed, criblé was also used to make the earliest metal prints on paper. Criblé was a method of dotting the plate with a hand punch; with punch and hammer; with a serrated, flatheaded tool called a matting punch; with various gouges; or, sometimes, with a hollow, circular-headed ring-punch. Criblé plates were relief printed like woodcuts. On most dotted prints, a black background dominates a fine lacelike design. Intaglio processes
Intaglio printing is the opposite of relief printing, in that the printing is done from ink that is below the surface of the plate. The design is cut, scratched, or etched into the printing surface or plate, which can be copper, zinc, aluminum, magnesium, plastic, or even coated paper. The printing ink is rubbed into the incisions or grooves, and the surface is wiped clean. Unlike surface printing, intaglio printing—which is actually a process of embossing the paper into the incised lines—requires enormous pressure. The major working methods for intaglio printing are engraving, etching, drypoint, and mezzotint. Intaglio processes are probably the most versatile of the printmaking methods, as various techniques can produce a wide range of effects, from the most delicate to the boldest. The intaglio print also produces the richest printed surface, as it is three-dimensional. Engraving
In engraving, the design is cut into metal with a graver or burin. The burin is a steel rod with a square or lozenge-shaped section and a slightly bent shank. The cutting is accomplished by pushing the burin into the metal plate. The deeper it penetrates into the metal, the wider the line; variations in depth create the swellingtapering character of the engraved line. After the engraving is finished, the slight burr raised by the graver is cleaned off with a scraper. The engraved line is so sharp and clean that it asserts itself even if cut over a densely etched area. In the print, the engraved line is notable for its precision and intensity. In engraving, the hand does not move freely in any direction but pushes the graver forward in a line; a change of direction is achieved by the manipulation of the plate with the other hand. Although copper, zinc, aluminum, and magnesium plates are used—and in the past soft iron and even steel were used—the best all-around metal is copper. It has the most consistent structure and is neither too soft nor too hard. Drypoint
Next to engraving, the drypoint is the most direct of the intaglio techniques. In printing, however, it represents the opposite end of the spectrum. Engraving is precise; drypoint is rugged, warm, and irregular.
Drypoint is made by scratching lines into metal plates with steel- or diamond-point needles. In this method the penetration into the plate is negligible; it is the metal burr raised by the point that holds the ink. Because the burr is irregular, it prints as a soft, velvety line. The angle of the needle has much more effect on the width of the line than the pressure does. If the needle is perpendicular to the plate, it throws burr on both sides, which then produces a thin double line; for wide lines the optimum angle is 60 degrees. Many artists use an electric graver to make drypoints. The oscillating point of the tool punches little craters into the plate. Because the line consists of thousands of these small craters, it is richer than the conventional scratched line made by the needle and stands up better to printing.
Copper plate is the best for drypoint. The plates are fragile because the burrs are easily flattened down by the printing pressure. Even a too vigorous wiping can damage a plate. Thus, unless the artist is satisfied with a very limited number of proofs (three or four), the plate must be faced with steel, a process in which steel is deposited by electrolytic means on the copper plate. This coating is very thin and, if it is properly done, the burrs are hardened without affecting printing quality. Zinc and aluminum, however, cannot be steel-faced. Mezzotint
In mezzotint the metal plate is roughened with fine burrs until it prints a rich, velvety black. The plate is then worked back toward the lighter values with scrapers and burnishers. For this reason, mezzotint is also called manière noire, or the “black manner.”
Mezzotint flourished throughout the 18th and 19th centuries and was primarily used for portraits or to reproduce paintings. None of the important printmakers of the past used the technique. After the invention of photoengraving, the technique of mezzotint was nearly forgotten, but a few printmakers have started to work again with this exotic medium.
The first step in preparing a mezzotint plate is to rough up the whole plate surface as evenly as possible. The tool used is the rocker, a blade with a curved serrated edge. The rougher the rocker, the heavier is the burr. The rocker is held with its cutting edge at a right angle to the plate, and the curved edge is rocked systematically over the entire surface. If this is properly done, the entire plate is covered with uniform burrs. Then the work with scrapers and burnishers begins. Where lighter tones are desired, the burr is gradually removed, and in the white areas the plate is burnished back to its original finish.
As with drypoint, mezzotint plates must be steel faced if a large edition is desired. The printing of mezzotints differs slightly from the printing of etchings or engravings. Since the layer of burr on the mezzotint acts as a blotting paper, the ink must be selected with this fact in mind. The inking and wiping must be done gently with soft rags. Printing pressure should be considerably less than that used for engravings or deeply etched plates. Crayon manner and stipple engraving
Invented in the 18th century, crayon manner was purely a reproduction technique; its aim was the imitation of chalk drawings. The process started with a plate covered with hard ground (see below Etching). The design was created using a great variety of etching needles (some of them multiple). After the design was etched in, the ground was removed and the design further developed with various tools. Fine corrections and tonal modifications were made with scrapers and burnishers. Finally, engraving was used for additional strengthening of the design. Pastel manner is essentially the same as the crayon manner except that it is usually used to imitate pastel drawings.