The Reason
An original Navitimer ref. 806 made in 1966 with Venus 178 movement
Functions
Manual winding with hours, minutes and small seconds at 9 o’clock. 12 hour recording chronograph and tachymeter/internal circular slide rule scales.
Movement height 7.10 mm, diameter 31.00 mm (14 ligne). Jewels 17. Power reserve 45 hours. Frequency 18000 VPH. Hand winding. 2-Button, 7-Column Chronograph Wheel. 30 Minute Chronograph Hand at 3:00, central 60 Second Chronograph Hand. Central Hour Hand, Central Minute Hand, Small Seconds Hand at 9:00
The case back is snapped in place and removed by using a case-knife.
The bezel, as with the case back is removed by using a case-knife. The bezel pushes onto an outer friction fitted brass ring upon which the outer slide-rule scale sits, housed around the dial.
The case is dust, apposed to water resistant. The bezel carries a UB (unbreakable) perspex glass held in place by compression. Early Navitimer examples such as this often show heavy signs of wear on the inner bezel section of the dial and rotating slide rule rings.
The movement removed from the case and the stem returned into position.
The hands and dial removed from the watch.
The Venus 178 base calibre used in early Navitimers.
The calibre was and remains one of the most reliable and enduring workhorse movements built in watchmaking history.
The balance assembly removed.
Although, compared to many modern calibres the frequency of 18000 vibrations per hour is low, the large balance common to many vintage watches could be adjusted to with in a few seconds per day.
The Venus calibre and logo normally hidden under the balance in view.
The Swiss anchor and cock removed.
The penetration of the Swiss anchor/pallet jewels into the escapement were adjusted manually.
The indexing pawl for the minute recorder wheel.
The return to zero hammers in the centre of the image and the main operating lever (start/stop) at the bottom.
The chronograph minute recorder and seconds wheels with their maintaining cock.
The heart-shaped return to zero cams being pushed to zero by their hammers.
A basic difference between Venus and Valjoux calibres was the origins of the force activating the hammers. With Valjoux, the force of the operators thumb or finger would push the hammers into their zero-ing position. With Venus the operators zero-ing action would release the hammers being held by a pin, under pressure from a spring within the mechanism to zero the cams. When the chronograph was next activated the hammers were lifted and their return to zero spring armed.
In the centre of the image is the coupling clutch, transmitting power from the upper 4th wheel (to the right) through to the chronograph seconds wheel to the left.
The small copper coloured spring in the centre pushes under the chronograph seconds wheel removing any unwanted slack. If a chronograph seconds hand ‘flutters’ it may be because this spring is applying insufficient pressure on the wheel.
Summary
This original Navitimer is rendered weak by comparison to its modern equivalents due to the vulnerability of the case and its lack of water resistance. But its overall solid construction assures that when properly cared for, it has the potential to be immortal.
The Navitimer is one of the iconic designs born during the vintage era of watchmaking. It is not only the most famous design to originate from Breitling but is one of the designs that defined a generation of watches that influenced an entire industry.
Many companies from Patek to Rolex used existing generic calibres, (the aforementioned brands tended to use Valjoux chronographs) and personalised them to their own requirements. This approach to watchmaking goes back hundreds of years and can be found even in obscure brands long forgotten and some of the most famous names in watchmaking history.
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