Guillochage
Chronoswiss Kairos Chronograph with elaborate guilloché dial
© Chronoswiss
Guillochage is a method of decorating surfaces with inscribed intersecting lines.
Most guilloché decorations consist of repetitive patterns of straight and curved lines which intersect to form textures. These can be engraved by machine or by hand, typically using a rose engine lathe. It is a special form of engine turning.
Guilloché is most commonly found on watch dials, subdials, and similar surfaces.
The processed surfaces are called guilloché. The craftsman performing this art is called guillocheur.
Patterns
Various patterns are possible in guilloché. Most are used separately from the overall term, with “guilloché” mainly used to refer to circular patterns.
Waffle
One popular texture for dials is waffle patterns. These are reminiscent of waffle irons, with deep, broad parallel lines intersecting at 90 degrees to form a uniform square surface of flat plateaus.
A similar texture, widely associated with Audemars Piguet is tapisserie (French for “Tapestry”), with uniform flat-topped square elements with a broad flat grid inset between.
Honeycomb or Diamond
Similar to waffle, honeycomb patterns consist of parallel lines intersecting at right angles. However, the lines are typically closer together and more narrow and often the pattern is rotated 45 degrees, creating a diamond pattern.
Hobnail
- See Also Clous de Paris
Hobnail, or Clous de Paris, is a similar pattern of intersecting straight lines but the cuts are made so as to create a uniform texture of pyramid shapes rather than flat plateaus.
Video
- Horlogery - The Guillocheur, 5:22 (engl.) © Haute Horlogerie.org (YouTube)