What is etching?
Etching is a printmaking process that dates back 500 years. The etching process involves sheets of metal, usually made of copper or zinc, and acid used to etch the print onto the metal. The artist can use complicated methods to create different effects, but always relies on acid to etch the plate. The more complicated the etching, the more time consuming and expensive it will be. To begin an etching, you must first coat a blank copper plate with wax. Using a steel etching needle, draw your intended picture through the wax and onto the metal. Once you have drawn your picture, the metal will be submerged into a bath of acid and left for about two hours. The acid will eat away at the copper that has been exposed by the needle to leave grooves, marks and textures in the metal. The plate is then taken out of the acid bath and the wax is cleaned off. The result will be a shiny, copper plate with the image etched onto it. This can be repeated again and again by rewaxing the plate. By rewaxing
“Etching” is the abrading or roughening of a selected area on a piece of glass, marble, granite, tile, or other substrate that produces a desired design on the surface. Two types of etching are acid etching and sandblast etching. For purposes of our application, as for glass etching, we will use the term “etching” to refer specifically to sandblast etching or abrasive etching.
A. Etching happens when acid in some form comes in contact with a polished marble or limestone surface. This causes a chemical reaction, which removes the polish, or roughens the surface of honed marble or limestone. Green marbles, such as the “jades” from China are resistant to etching, and granite is impervious to any common household acids.
Etching is a chemical finishing process that produces a silver-white surface, often referred to as frosted or matte. In the etching process, the aluminum extrusion is passed through a warm chemical solution that removes the natural oxidation which has formed since extruding. It’s then rinsed, and passed through a nitric acid bath, or desmutting process, to remove undissolved surface alloy constituents or impurities, and rinsed again. Then, to preserve its appearance, the extrusion is usually anodized.
