Certina Caliber 28-10: A Compact Manual-Wind Movement from the Post-War Era

The Certina Caliber 28-10 is a manual-wind mechanical movement introduced during the post-WWII years—a period marked by increased demand for slimmer, more accurate wristwatches. This caliber reflects Certina’s commitment to creating reliable and compact timekeeping mechanisms, and it was primarily used in smaller men’s or unisex watches during the late 1940s and 1950s.

Engineered for precision and serviceability, the 28-10 offered excellent performance in a reduced size, ideal for elegant dress watches and discreet timepieces of the mid-20th century. Though not as robust as the later 25-series automatics, this caliber paved the way for Certina’s reputation for mechanical reliability and Swiss quality.

Technical Specifications

The movement’s compact size and relatively thin profile made it ideal for the restrained case designs of the time, especially in gold-filled or stainless steel dress watches.

Mechanical Layout and Function

The 28-10 follows a classic manual-wind architecture:

• Crown and ratchet wheel on the top plate for winding

• Barrel-driven gear train

• Sub-second pinion at 6 o’clock

• Swiss lever escapement

• Traditional balance wheel and hairspring system

The movement uses a bridge-style layout with polished plates and beveled edges on many variants. The basic design was built for simplicity and long-term operation with regular servicing.

Distinct features include:

• A clean and minimalist gear train, reducing internal friction

• Reliable manual winding action with firm tactile feedback

• Optional shock protection added in later versions

• Smooth-running small seconds complication, a signature of the era

Watches Using Caliber 28-10

Certina deployed this movement in mid-20th century hand-wound watches, typically aimed at the dress or daily wear market. These watches featured:

• 34 mm or smaller case sizes

• Slim bezels and classic lug shapes

• Sub-seconds dial at 6 o’clock

• Applied indices or painted numerals

• Dials signed “Certina” and often marked “Swiss Made” at 6 o’clock

Cased in steel, gold-filled, or 14k gold, these watches offered a subtle elegance that appealed to professionals and collectors alike. The 28-10's small footprint made it suitable for both men’s and mid-size women’s watches in the 1950s.

Service and Longevity

Watchmakers appreciate the 28-10 for its simple construction and ease of regulation. Most versions are fully rebuildable, and many parts—like mainsprings and jewels—are compatible with other compact Swiss calibers of the time.

Watchmaker notes:

• Clean pivots and oil lightly with Moebius 9010

• Inspect the click spring and mainspring barrel during service

• If present, check Incabloc or similar shock absorbers for function

• Be careful when removing hands due to the close tolerance of sub-second wheels

Even after more than 70 years, many examples of the 28-10 still perform well when properly maintained, making it a testament to Certina’s engineering.

Collector Perspective

While not a rare movement, the 28-10 is valued by collectors who appreciate:

• Understated elegance

• Mid-century Swiss craftsmanship

• A true vintage wristwatch aesthetic

Watches housing this caliber often retain strong vintage appeal, particularly if the dial and case remain original and unpolished. The small seconds display is a nostalgic feature that continues to attract vintage purists.

Conclusion

The Certina Caliber 28-10 stands as a quiet but important piece of post-war Swiss watchmaking history. With its compact manual-wind design, it delivers accuracy, simplicity, and elegance in a timeless package. Whether you're a collector, restorer, or enthusiast, this movement offers a satisfying blend of mechanical charm and everyday functionality.