Thehistory of the Calibre 11

Starts at the end of 1965. As Büren had pioneered the production of micro-rotormovements, Gérald Dubois (of Dépraz & Co., a chronograph specialist)figured out that these would be thin enough to be the base for a modularchronograph movement. Dubois contacts Hans Kocher of Büren Watch Co. SA. Inneed of commercial partners, they manage to convince first Jack Heuer and thenWilly Breitling to support the project. On February 2nd, 1966, an agreement issigned. The four-party Chronomatic consortium is born, including two rivalbrands teaming up to develop their own automatic chronograph. Forconfidentiality purposes, the development is code-named Project 99.

 The convention signed onFebruary 2, 1966, between Dépraz & Co., Heuer-Léonidas SA and LéonBreitling SA. The partners asked Büren Watch Co. to build the blanks and the automaticmovement of an automatic chronograph, the basic execution of which isdesignated by calibre No. 111. They have an exclusive right to use thiscalibre. They plan to have Dépraz develop and manufacture the chronographmechanism to equip this calibre.

Büren is in charge of the base calibre. Dépraz of the chronographmechanism. Three brands – Heuer, Breitling and Hamilton (who acquired Burenduring the development process) – will fit the movement inside their watches. Apatent application for the Calibre 11 is filed in September 1967. At the end of1968, about 100 pre-production movements are assembled in prevision of the 1969Basel fair. On March 3rd 1969, the movement is officially presented,simultaneously in New York and Geneva. A month later, the three brands presenttheir first chronographs at the 1969 Basel fair. With the practicality andcomfort of automatic winding, the chronograph becomes a staple of motorsport…the Calibre 11 is used to power iconic watches by Heuer (Carrera, Monaco,Autavia), Breitling (Chrono-Matic) and Hamilton (Fontainebleau). And later byother brands such as Bulova, Kelek, Zodiac, Elgin, Stowa…

So, who won the race?

Zenith’s automatic chronograph was the first to be unveiled to theworld. It was presented during a press conference in January 1969 andchristened El Primero (“the first” in Spanish). The reality is a bit morecomplex. There are endless debates about which was the first automaticchronograph, as both the Seiko and the Chronomatic movements were announcedlater the same year. What’s more, El Primero was not the first to hit themarket. But the controversy about who came first doesn’t really matter anymore…what is important is the impact that these movements had on watchmakinghistory. Since then, the automatic chronograph has remained one of the mostpopular complications.

THE CALIBRE 11

The Calibre 11 is a 17-jewel modular chronograph measuring 31mm x7.7mm. This modular architecture implies first a base movement, a micro-rotorautomatic calibre made by Büren, in charge of the timekeeping part. Beating at19,800 vibrations per hour, it boasted 42 hours of power reserve. Manufacturedby Dépraz, the lever chronograph module is assembled on the backside of thebase movement. This movement has a bi-compax display, with a 30-minute counterat 3 o’clock and a 12-hour counter at 9 o’clock – no running seconds sub-dial.The date is indicated at 6 o’clock. The unusual crown position, at 9 o’clock atthe opposite of the chronograph pushers, is a signature feature of themovement.

THE CALIBRE 11 AND ITS EVOLUTIONS

Like most movements, the Calibre 11 has been optimized several timesover its lifetime. As early as 1969, a barrel spring providing less torque isused. The date jump mechanism is adapted. The sliding pinion is changed andmade in steel.

 In 1971, a variant running at21,600 vibrations per hour and named Calibre 12 is introduced. Itbecomes the main product of the calibre family. It uses a stronger barrelspring. The gear train and balance wheel are adapted. The chronograph hammer ismodified to improve shock-resistance.

This is a beauty, so why is this watch so special and rare??, it is fully serviced, for those who do not know how much it cost to service Cal 11 $500 to $850, it is in original condition, come with original Hamilton bracelet which is very rare (The bracelet along is worth $$, no one has one, which also means it was not worn much) also come with Hamilton Green Long box. It is very rare to find a watch this old with beautiful long black Hamilton box. Defiantly a collector watch. Please look at all the pictures, as they are part of the description. The watch is working and Serviced. This is a highly collectible watch. Very few left with this rare movement. Sure, to increase in value overtime, and a great addition to your collection. The condition of the watch is the same as it appears in the photos.   The watch is working and is part of our new Certified Pre-Owned CPO Program.  Contact me if you have any questions first.