right|thumb|[[Charles Lindbergh's famous aircraft, the Spirit of St. Louis. The ' pattern on the metal panels is one type of engine turning.]]
Engine turning is a form of ornamental turning. The finishing technique may use lathes or engines to produce a pattern. Aluminium is often the metal chosen to decorate. The technique has been used in various industries, including aircraft and document verification.
Description
Engine turning is a form of ornamental turning. The technique geometrically applies a single-point cutting tool to produce a decorative metal surface finish pattern.
Traditionally, engine turning referred to Guilloché engraving. In the 20th century, it also came to refer to the different process of ' (also known as spotting, jewelling, perlage), which is a fine geometric pattern of overlapping circles abraded onto the surface.