Engraving in watchmaking is not a single technique: it's a family of processes that share controlled material removal from surfaces—whether the case, dial, or movement components. The difference between mediocre and extraordinary results almost always lies in the hand guiding the tool—or in the decision to replace it with a machine.
The oldest and most debated form is guilloché. It's executed on rose engines or straight lathes—mechanical machines from the 18th and 19th centuries, some still without electricity, like those used by Atelier Renzetti on the Redentore Utopia II dials. The lathe guides the tip along a repeated geometric path, but it's the artisan who regulates pressure, depth, and speed. The result—barleycorn, sunburst, clous de Paris, hobnail—is never identical to itself under different angles of light. When we speak of hand-guilloché, as executed by Kari Voutilainen on brass plates, every groove is the result of a deliberate choice. Gerald Charles's meta-guilloché adds a step: engraving, protective coating, second engraving, coating removal. The rounded edges that result produce a sparkle that single guilloché could never achieve.
Tremblage is something different: a vibrating tool incises the surface creating a granular microstructure that diffuses light similarly to velvet—tonal variations change with angle. The gratté technique, executed with a multi-blade tool, produces instead a more regular pattern, close to the appearance of fabric. Both are worked on precious or semi-precious metals; on 925 silver, as in the Ancestra Yao dial, the material's response is particularly legible.
Champlevé is engraving in service of enamel: cavities are carved into the metal, then filled. Flinqué does the opposite in terms of effect: you engrave first, then cover with translucent enamel that lets you see the pattern beneath, amplifying its depth. These techniques require coordination between engraver and enameler—two crafts that rarely inhabit the same body.
Laser has opened possibilities that the burin cannot reach in terms of repeatability and geometric fineness—the 0.55 mm grids of the Big Bang Tourbillon GOAT Edition or the textile textures of the Royal Oak Concept are examples. But laser doesn't replace the hand: on James Lamb's Linea Edition, Joanne Ryall works the titanium dial under a microscope because only this way can she maintain sharp edges and insert gold into the groove without widening it. From the bench I've learned one thing: when an engraved dial looks identical to itself from all angles, the work hasn't been finished well.