In 1950 IWC released its first generation automatic movement (81) designed by IWC’s Technical Director Albert Pellaton who came up with an ingenious pawl-winding system. The calibre 81 had a sub second design that was almost instantly dropped for the sweep second version calibre 85. In 1952 the movement had minor upgrades and was renamed 852 the following year a date variant calibre 8521. This was produced until 1958 when the updated 853 and 8531 was introduced, this movement lasted until 1964 when it was replaced by calibre 854-8541. The 8541 stayed in production all the way up to 1990
family/generations:
81. Sub second design. (1950-51 ca 1800 made)
85. Sweep second (1950-1953 ca 8400 made)
852. Sweep second now beating at 19.800 B/A
8521. Sweep second date (1953-1958 13200) (1953-1958 49200 made)
853. Sweep second (1958-1963 85200 made) Now with Breguet hairspring and Reeds regulator.
8531. Sweep second date (1958-1964 55200 made)
854 (1964-1976 40200made) New regulator design and thinner 4.85mm from 5.6mm
8541 (1964-1990 ??made)
IWC 81-8541:
- Made from a prox 1950-1990
- Made in Switzerland
- Power reserve around: 44h
- 21-25 Jewels
- 18000-19800 B/A
- Lift angle 52°
- DM 28.2mm
- H 5.6-5.9mm
All variants have a nice finish on the bridges in the form of spiralling cote de geneve texture. The edges of the bridges are beveled and the text guilt. Rhodium plating and highly polished screws.
Top surface finish on bridges: 9 Points
Surface finish on screws: 10 Points
Surface finish on ratchet and ratchet wheel: 7 Points
Movement Jeweling: 8-9 Points
Movement design innovation (1950): 9 points + 1 points from 1952
The IWC base plate has an overall good finish fully covered in perlage. Winding, date and setting mechanisms are well made, screws are highly polished. Gear train has a good finish. Setting the time feels balanced and smooth. Winding a little raspy.
Base plate finish: 9 Points
Setting and winding mechanism: 7 Points
Gear-train finish: 9 Points
Date change snappiness 11.45-12.00: 8 Points*
Movement durability: 7 Points
Bi-directional automatic device is well made and very effective. Only downside it can wear when excessively manually wound effecting the movement durability.
Autowinder mechanism: 9 points*
Reeds Micro regulator. 853 series.
Bonus points: 3*
Micro regulated stud carrier (beat error) and time adjustment. 854 series.
Bonus points: 6*
The IWC’s are precise movement when in good condition.
Accuracy: 10 points
Power reserve of 44 hours is acceptable
Power reserve: 8 Points
IWC 81-8541 points summary:
Surface finish on bridges and top side of base plate: 9
Surface finish screws: 10
Surface finish on ratchet and ratchet wheel: 7
Movement Jewelling: 8-9
Movement innovative design for ca 1950: 9-10
Base plate finish: 9
Setting and winding mechanism: 7
Date change snappiness: 8*
Gear-train finish: 9
Movement durability: 7
Total bonus points: 1-8*
Autowinder: 9
Accuracy: 10
Power reserve: 8
Grand total Automatic: 102-118
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