Engraving, Etching and Aquatint:
These three techniques share the same basic principle. The printmaker cuts shallow grooves or pits into an otherwise flat metal printing plate. Ink is applied to the surface of the plate and wiped off with a rag, leaving ink behind only in the shallow grooves. Moistened paper is laid on the inked plate and both are squeezed together with a mechanical, hand-cranked press. Under enormous pressure, the paper is pushed into the grooves, which allows the ink to soak into the desired areas.
Engraving, etching and aquatint differ in the manner in which grooves or pits are cut into the metal plate.
Engraving:
A way of drawing into an intaglio plate without using acid and without creating a burr that clings to the lines. Engravings have wiry-looking clean lines. The artist uses a faceted tool called a burin that he or she pushes, rather than drawing with it in a natural way. The blade’s two sharp edges remove the displaced metal from the plate. Engraved lines have tapered ends because the tool must enter and leave the plate gradually.
Etching:
An image printed from a metal plate that has been incised by acid. The term also describes the activity of biting a metal plate in acid. In general, etching processes involve coating the plate with an acid-resistant ground, removing the ground in the image areas, then submerging the plate in a bath of diluted acid. Soft and hard ground etching are done in this way. Aquatint, also a form of etching, uses similar principles but plate preparation is more complex. Aquatint is often etched in a bath of acid, but also may be etched by spit biting, or painting the acid directly on the plate. For ground is any acid-resistant material used to protect an etching plate from acid. The most common grounds are wax, asphaltum, shellac, rosin, and soap.
Aquatint:
This is a variation of the etching technique that is the most common method of creating tones in etching. Irregular grains of rosin (or another granular acid-resistant material) are applied to a plate, then the plate is heated, causing the grains to melt slightly and adhere to the plate. The acid bites around the individual grains, and the plate is left with a rough surface, or tooth, that holds ink. Rosin can be sifted onto the plate by hand, which results in an irregular bite, or it can be dusted evenly onto the plate in an aquatint box equipped with a fan or other means of creating a dust storm. Spit bite, soap ground, and sugar lift are ways of using aquatint.
Sugarlift Aquatint:
An aquatint technique that allows an artist to paint a dark form on a white background. The artist draws with a sugar syrup, then an aquatint ground is substituted for the syrup before biting. To accomplish this, asphaltum is painted thinly over the entire plate including the image. After the asphaltum is dry, the plate is put in a bath of warm water until the sugar swells and lifts, leaving the metal exposed in the image area. Rosin is then dusted over the plate, and the plate is etched.