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You are here: Home / Movements / ST1812

ST1812

Last Update: June 28, 2019

Brand:Sea-Gull, Tianjin
Family:
Unknown
Height:
Jewels:21, 23
Reserve:41 hours
Frequency:28,800 A/h
Winding:Automatic, Bi-Directional Automatic Winding, Central Rotor Automatic Winding
Diameter:
  Complications:Date, Hacking Seconds, Hand Winding, Quick Date Correction
Hands:Central Hour Hand, Central Minute Hand, Central Seconds Hand, Date Window at 3:00
Distinguishing Technical Characteristics
Central-Rotor Automatic
Clockwise Balance Cock
Screw Regulator
Central Rotor
Production: 2001 – Current
1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s 2000s 2010s 2020s

Cal. ST1812, produced by Tianjin Seagull Corporation, is an automatic movement with a central date wheel. The design is similar to the ETA 2892A2.

Besides finishing, there are some differences between Cal. ST1812 and ETA’s Cal. 2892A2. Cal. ST1812 uses a traditional fixed pin balance instead of the ETACHRON balance in the 2892 and has a fully slotted excentric in the regulator. The balance bridge is mounted using holes instead of pins as on the ETA. The fourth wheel on Cal. ST1812 also have six instead of eight spokes and places the winding jewel on the post bearing instead of the bridge. Some examples have an extra jewel for the barrel arbor.

Images are taken from official publications and are used here for commentary and educational purposes. Copyright is held by the original owner as noted.
External Link
Manufacturer Link

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