2156_Bulova 6CK

Bulova 6CK: A Slim and Elegant Manual-Wind Movement

The Bulova 6CK is a manual-wind mechanical movement that was introduced in the 1950s, tailored for ladies’ wristwatches that emphasized slimness, precision, and elegant styling. Part of the wider Bulova family of small calibers, the 6CK fits into the 6-ligne category, ideal for fashion-forward and compact timepieces.

Despite its petite dimensions, the 6CK delivered consistent performance and solid engineering—a testament to Bulova’s manufacturing capabilities during its mid-century peak.


Technical Specifications

Feature Bulova 6CK
Movement Type Manual-wind (hand-wound)
Diameter ~6¾ ligne (~15.3 mm)
Height ~3.6 mm
Jewels 17 (common configuration)
Beat Rate 18,000 vibrations/hour (2.5 Hz)
Power Reserve ~36–40 hours
Functions Hours and minutes
Shock Protection Yes (KIF or Incabloc system)
Seconds Hand None (time-only configuration)

The movement has no central or subsidiary seconds, allowing for a minimal, clean dial design—a hallmark of many 1950s and 1960s ladies' dress watches.


Movement Architecture and Design

The Bulova 6CK is constructed with two main bridges: one supporting the mainspring barrel and center wheel, and the other holding the gear train (third, fourth, and escape wheels). Its lever escapement is paired with a small balance wheel, fitted with a flat hairspring and protected by a shock-resistant jewel setting.

Notable features include:

  • Traditional ratchet and crown wheel on the top plate

  • Fine timing regulator on the balance cock

  • High-polish gear train wheels for efficient torque transfer

  • Minimalist motion works with sturdy setting components

This structure allows for easy serviceability, a crucial advantage for watchmakers working with small-scale vintage movements.


Applications in Bulova Watches

The 6CK was used in a wide variety of ladies’ watches sold in the 1950s and early 1960s. These watches were typically:

  • Gold-filled or solid gold cases

  • Bracelet or bangle-style watches

  • No second hand, resulting in a simple two-hand dial

  • Designed to complement evening wear, formal occasions, and mid-century fashion

Models powered by the 6CK can be found in both American and Swiss-produced Bulova watches. Often, they were sold as part of gift sets or seasonal promotions, making them popular with the public and widely distributed.


Service Considerations

Though small, the 6CK is straightforward to disassemble, clean, and lubricate, as long as the proper tools for 6-ligne movements are used.

Watchmaker tips:

  • Ensure the mainspring is replaced with a modern alloy version if fatigued.

  • The balance staff is delicate and may require replacement from donor movements.

  • Use Moebius 9010 or 9020 oils on pivots and escapement; 8200 grease for barrel arbor lubrication.

  • Inspect clutch and winding wheels for wear, especially in frequently-used watches.

With regular maintenance, the 6CK remains a dependable performer, often accurate to within 30–60 seconds per day.


Collector Notes and Market Value

Watches containing the Bulova 6CK movement are valued for their mid-century styling, historical significance, and quality construction. While not high-dollar collector items like chronographs or complicated watches, they hold appeal due to:

  • Authentic post-war craftsmanship

  • Association with vintage American watchmaking

  • Excellent restoration potential

  • Often found in pristine cosmetic condition

These watches also make great entry-level vintage timepieces for collectors looking to explore Bulova’s rich history without major investment.


Conclusion

The Bulova 6CK is a fine example of compact mechanical engineering, designed to power stylish and elegant ladies’ watches during Bulova’s golden era. It is practical, refined, and built to last. For watchmakers, it presents a clean and logical design to service. For collectors, it’s a charming slice of American horological heritage. And for those simply wearing it—it continues to tick with timeless grace.

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