The Tissot caliber 27B-2 is a manual-winding mechanical movement produced in the mid-20th century, as part of Tissot’s long-standing and respected 27-series of in-house movements. The 27B-2 is a variant of the original 27B, updated to meet evolving production and watch case requirements. These movements were used in a variety of elegant, time-only wristwatches, particularly during the 1940s to 1960s.

Overview of the Tissot Caliber 27B-2

The 27B-2 was designed for reliable daily use, offering a clean, classic mechanical layout. It typically features:

• Manual winding operation

• Hours and minutes via central hands

• A small seconds subdial at 6 o’clock

Watches equipped with this movement were usually housed in stainless steel or gold-plated cases, and often featured minimalist dials with Arabic numerals, baton indexes, or a combination of both. These watches were marketed as functional, Swiss-made timepieces for both formal and casual wear.

The “-2” suffix indicates an evolutionary upgrade over the base 27B, likely involving changes to the gear train layout, bridge design, or compatibility with newer case sizes.

Technical Specifications

• Type: Manual winding

• Functions: Hours, minutes, small seconds

• Jewels: 15

• Frequency: 18,000 vibrations per hour (2.5 Hz)

• Power Reserve: Approximately 40 hours

• Diameter: ~27 mm (approximately 12 lignes)

• Height: ~4 mm

• Shock Protection: Varies by production year (early models without, later with basic shock systems)

• Finish: Functional Swiss style; matte plates, blued screws, Tissot-stamped bridges

Like other Tissot 27-series movements, the 27B-2 used a Swiss lever escapement, offering stable timekeeping and good serviceability.

Maintenance Guidelines

To ensure proper performance, the 27B-2 should be professionally serviced every 4 to 6 years. Vintage movements of this kind are generally robust but require lubrication and adjustment to prevent wear.

A full service typically includes:

1. Complete disassembly of the movement

2. Ultrasonic cleaning of all parts

3. Inspection and replacement of worn components such as the mainspring, crown, or pivots

4. Lubrication using modern oils

5. Reassembly and fine regulation

6. Case cleaning, and gasket replacement if the watch includes any form of water protection

Servicing should be carried out by a qualified watchmaker experienced with vintage Swiss movements. Replacement parts may need to be sourced from donor movements.

Known Wear Areas

• Mainspring fatigue is common in older movements, resulting in reduced power reserve

• Worn pivots or jewels, especially in the balance or escape wheel

• Crown and stem wear, affecting winding smoothness

• Dial feet or mounting tabs, sometimes damaged during previous repairs

• Small seconds wheel, which may wear faster due to constant engagement

Handling and Storage Tips

• Wind once daily, stopping when resistance is felt

• Avoid moisture—watches from this era are rarely water-resistant

• Keep away from magnets, which can affect timekeeping accuracy

• Store in a dry, stable environment, ideally in a soft-lined box or watch pouch

Collectibility

The Tissot 27B-2 is not considered rare or highly collectible on its own, but it carries value for those interested in:

• Vintage Swiss watchmaking

• Manual-wind mechanical movements with classic design

• Affordable, serviceable watches with historical charm

• Tissot’s heritage as a respected maker of mid-century timepieces

These movements are often found in well-preserved vintage watches, offering both functionality and character.

Conclusion

The Tissot caliber 27B-2 is a dependable and straightforward manual-wind movement that represents the quality and practicality of Tissot's mid-century mechanical engineering. With regular maintenance and respectful use, this movement can continue performing for generations. It remains an excellent option for anyone interested in vintage mechanical watches that combine Swiss reliability, understated design, and timeless appeal.