Technical sheet
Sellita’s 2892-A2 clone: thin, self-winding, 4 Hz, 25 jewels and up to 56 h.
Features
Going train
| Arbor | Wheel | Pinion | True speed |
|---|---|---|---|
| Mainspring barrel | 84 | — | 1 rev / 7 hours |
| Center wheel | 80 | 12 | 1 rev / hour |
| Third wheel | 75 | 10 | 8 rev / hour |
| Fourth (seconds) wheel | 84 | 10 | 1 rev / minute |
| Escape wheel | 20 | 7 | 12 rev / minute |
Disclaimer
An approximation of the Sellita SW300-1 layout from public drawings and photographs, not a manufacturer-accurate replica. 28,800 vph (4 Hz), 25 jewels, Ø 25.60 mm casing diameter (26.20 mm overall), 3.60 mm height, date with quick setting, stop-second, fine timing device, a 51° lift angle and a power reserve of 50 h minimum / 56 h typical are Sellita’s published figures. Older specifications give 42 h; the press dates the longer-running barrel to 2020 (Time+Tide) or 2021 (Monochrome). Bidirectional winding is from Caliber Corner (Sellita does not state the direction). As a clone of the ETA 2892-A2 it is modelled on the 2892-A2 geometry: tooth counts, wheel sizes, the barrel position, the bridge outlines hidden under the rotor and the seconds drive are an approximation, with the fourth wheel turning once a minute and the escape wheel matching 28,800 vph. Parts are drawn larger than life and the stack is much taller than the real 3.60 mm. The escapement motion is a kinematic model, not a physics simulation.
Sources