MITKA

Omega calibre 26.5 review.

Omega started making calibre: 26.5 about 1927. It had a life span well into the late 1940’s. The movement was updated during it’s production run spawning many different variants. The Omega calibre 26.5 is essentially a miniature pocket watch movement that was suitable for the wrist. Several variants where made during it’s production run:

26.5 : bimet. balance
26.5T1: bimet. balance
26.5T2: bimet. balance
26.5T2 PC: bimet. balance, Incabloc
26.5T3: monomet. balance
26.5T3 PC: monomet. balance, Incabloc
26.5T3 PC AM: monomet. balance, antimagnetic, Incabloc
100: =26.5T3 PC AM since 1949

Omega Calibre: 26.5

  • Made approximately: 1927-1940’s 
  • Made in Switzerland
  • Power reserve 37h
  • 15 Jewels 
  • 18000 B/A
  • DM 26.5mm
  • H 3.95mm

Surface finish is not decorated, but has a very fine finish. Screws are polished and have a good finish. The bridges are rhodium plated. 

Surface finish on top side of the plate and bridges: 8 Points

Surface finish on screws: 8 Points

Surface finish on crown and ratchet wheel: 6 Points

Movement Jeweling: 6 points 

The movement has a pretty standard sub-seconds layout.

Movement design innovation (for ca 1927):  6 points

The Omega base plate has starburst finish. They sometimes come with perlage finish. Winding mechanisms are well made, but with a low finish on the screws. Gear train has a good finish. Setting the time and winding feels balanced. 

Base plate finish: 7 Points

Setting and winding mechanism: 7 Points

Gear-train finish: 7 Points

Movement durability: 7 Points

Balance upgrades are common. Here is an example of early shock protection system. The last models had Inca shock.

Potential bonus points: 3*

A bonus feature is the steel ratchet wheel washer that protects the balance bridge from wear. 

Bonus points: 2

All variants of the calibre: 26.5 all had Breguet hairsprings and in good condition will keep good time.

Accuracy: 8 points 

Power reserve of 37 hours is acceptable

Power reserve: 6 Points

Omega calibre: 26.5 points summary: 

Surface finish on bridges and top side of base plate: 8

Surface finish top screws: 8

Surface finish on ratchet and ratchet wheel: 6 

Movement Jeweling: 6

Movement innovative design for ca 1927: 6 

Total bonus points: 2-5*

Base plate finish: 7

Setting and winding mechanism: 7 

Gear-train finish: 7

Movement durability: 7

Accuracy: 8

Power reserve: 6

Grand total: 78-81*

*Inca shock. 

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