Orbe Cadran 38
An automatic wristwatch, thirty-eight millimetres across, with a green fired-enamel dial, brass hands and small seconds at six.
The dial
Everything on the face is arranged around the vertical line from twelve to six. The date sits at three, where the crown is, so nothing else breaks the symmetry.
Enamel
A copper disc is dusted with powdered green glass and fired in a kiln three times. Each firing deepens the colour and levels the surface, so the green lies under glass rather than on top of paint.
Applied indices
The hour markers are cut from brass and polished on two facets, one bright and one shaded, so they catch light from either side. Twelve is doubled; three and six give way to the date and the seconds.
Small seconds
The seconds turn in a recessed sub-dial at six, cut with fine concentric rings. A railway minute track with printed five-minute numerals runs around the edge.
Inside the case
Seven parts, taken apart along one axis. Everything above the dial protects it; everything below keeps it running.
- Crystal
- Domed sapphire, 2.2 mm at the centre. The anti-reflective coating is on the inside face, where it cannot wear off.
- Bezel
- A narrow polished ring pressed onto the case, kept thin so the dial can be as wide as the case allows.
- Case and lugs
- Stainless steel in a pale-gold finish, brushed on the flanks and polished on top. The lugs are drilled for a 19 mm strap.
- Dial and hands
- The enamel dial with its applied markers, a date wheel beneath the window at three, and faceted dauphine hands in brass.
- Movement
- Calibre OR-21, finished with straight stripes across the plates and set in a steel spacer ring.
- Rotor
- A brass half-disc on a ball bearing. It swings with the wrist and winds the mainspring in both directions.
- Caseback
- Screwed down onto a rubber gasket, with a sapphire window over the movement. Water resistant to 50 metres.
The movement
Winding. Each movement of the wrist turns the rotor, and the rotor tightens the mainspring. On days you do not wear it, a few turns of the crown do the same.
Power reserve. Fully wound, the mainspring runs the watch for about 42 hours. Taken off on Friday evening, it is still running on Sunday morning.
Beat rate. The balance wheel swings 28,800 times an hour, eight beats every second. That is why the small seconds hand glides rather than jumps.
Setting. Pulling the crown out to its last position stops the seconds hand, so the watch can be set against a reference to the second.
Rate. Each movement is regulated in five positions. Expect it to gain or lose a few seconds a day, and to settle into a habit you can learn.
Specifications
| Reference | Cadran 38 |
|---|---|
| Case diameter | 38 mm |
| Thickness | 10.6 mm with crystal |
| Lug to lug | 45.5 mm |
| Lug width | 19 mm |
| Case | Stainless steel, pale-gold finish |
| Crystal | Domed sapphire, anti-reflective inside |
| Caseback | Screw-down, sapphire window |
| Water resistance | 50 m |
| Dial | Green fired enamel, applied brass indices |
| Functions | Hours, minutes, small seconds, date |
| Movement | Calibre OR-21, automatic, hand-winding |
| Frequency | 28,800 vibrations per hour (4 Hz) |
| Jewels | 25 |
| Power reserve | About 42 hours |
| Strap | Dark green calf leather, pin buckle |
| Weight | 54 g on the strap |
Kept on the wrist
Worn every day, it winds itself. Left on a shelf, it runs for a day and three quarters, and a few turns of the crown start it again.