Hi Geordie
Are you talking about pattern turning ?.
The devices used to make these patterns are variously called "rose engines" or "geometric lathes"
Engine Turning refers to a fine geometric pattern that can be inscribed onto metal as a finish.
Aluminium is often the metal chosen but any metal can be finely machined to produce intricate repetive patterns that offer reflective interest and fine detail.
Engravings produced by engine turning are often incorporated into the design .
The resulting graphics are called Guilloches.
http://www.ganoksin.com/orchid/archive/200602/msg00003.htm
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"geometric lathes"
A geometric lathe is/was used for making ornamental patterns on the plates used in printing bank notes and postage stamps.
It is sometimes called a Guilloché lathe.
It developed early in the nineteenth century when efforts were introduced to combat forgery, and is an adaptation of an ornamental turning lathe.
The lathe was able to generate intersecting and interlacing patterns of fine lines in various shapes, which were almost impossible to forge by hand-engraving.
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Bj
