Ancre Genève Horological atelier — since 1911

GenèveSince 1911Calibre A—21

Everything worth seeing is smaller than you think.

We make movements, and repair the ones nobody else will touch. The one below is running on your clock — the same gear ratios a Swiss going train has used for a century.

02 — Atelier

A mechanical watch is a machine that loses a second a day and is considered excellent for it. Everything in it exists to make one small wheel turn at exactly the wrong speed, very consistently.

Restoration

Complete services, and the ones that need a part made because the part has not existed since 1954.

Calibres

Three in-house movements, all hand-finished — anglage, côtes, perlage — on surfaces the owner will never see.

Regulation

Adjusted in five positions over fourteen days. A watch that keeps time on a bench is not a watch that keeps time on a wrist.

03 — The movement

Calibre A—21

Not a picture of a movement. The wheels below are generated from tooth counts and a pressure angle, meshed at their true pitch radii, and turned by your system clock. Zoom in far enough and the bridge is engraved.

×1.0 Movement Calibre A—21, 30mm
Specification — the going train in numbers
Gear ratios of calibre A—21
WheelTeethPinionOne turn in
Barrel726 hours
Centre80121 hour
Third75107 min 30 s
Fourth80101 minute
Escape1553.75 seconds
Balance4 Hz · 28,800 A/h

6 × 8 × 7.5 = 360, so one barrel turn is six hours and the minute hand comes out at one turn per hour exactly.

04 — Calibres

Three movements

05 — The bench

Four hands, one loupe

06 — Contact

Bring us the difficult one.