Metal engraving is achieved in a number of different processes, for example, by using specific tools such as burins, liners and etching tools, or by machines which use laser cutters, or through a process of acid etching or chemical milling.
There are numerous purposes for metal engraving such as brake rotors and fuel plates for the automotive industry, cathodes, implants and stents for the medical industry and long-lasting stencils.
Engraving is also used on a number of different commercial objects, including jewelry such as rings and bracelets, guns or other specialty tools, and trophies, medals and plaques etc.
For industrial purposes, engraving is part of the manufacturing process for stencils, circuit boards and printing plates, and to create components requiring small grooves or holes. Metal etching, a similar process to engraving, can also be used to remove a layer of a metal in order to meet weight restrictions for certain items. After the metal has been etched, burr marks or imperfections may be smoothed or burnished away.
Traditionally, all engraving was done by hand through the use of a burin or cutting tool. This was used to scratch or depress the surface of the metal along a pattern in order to create grooves in the form of the desired image. While hand metal engraving is less popular than before, it is still used in some specialized industries such as small decorative pieces, jewelry and musical instruments.
More common in the process of engraving today are CNC and CAD controlled machines which are able to process a range of materials and dimensions, including straight or curved surfaces. The computer of these machines controls the laser’s or cutter’s direction, pressure and speed resulting in a precise image or design with clean, fine lines.
Another type of engraving or etching which is used for precision results and close tolerances is electro discharge machining. Chemical milling using acids or bases to etch materials can be used with some metals including stainless steel, copper, brass, nickel and silver.
Photochemical etching uses a photoresist as a masking layer in order to achieve the desired pattern on a metal part. It is a low-cost alternative that provides high quality workmanship in relatively quick turnaround times.