Carl F. Bucherer’s In-House Outrunner Caliber Goes to Work


In July, 2007, Carl F. Bucherer acquired its long-time movement collaborator Techniques Horlogères Appliquées SA and renamed it Carl F. Bucherer Technologies SA. The team got to work straightaway, and at BASELWORLD 2008, they announced their first in-house movement, the CFB A1000. Not content to create a standard, cookie-cutter movement, CFB instead introduced something truly innovative: an automatic movement with a peripheral winding rotor. Fast forward to 2009, and the movement, with some added complications, finds a home in the new Patravi EvoTec DayDate.


Let’s start with the movement. Most automatics use a centrally-mounted rotor. These are efficient, but the oscillating weight blocks the view like Shaq in a movie theater. Micro-rotors improve the view, but they can lead to compromises such as a smaller balance wheel and increased shock vulnerability. CFB’s so-called “outrunner” design combines the technical values of a central rotor and the aesthetic advantages of a micro-rotor. Add into the bargain that it’s a bi-directional winding system, and CFB has clearly achieved something special.

Most companies would have stopped there, content to have created a movement that runs circles around other designs (pun intended). CFB pressed on however, incorporating additional innovations, such as the winder’s mounting and shock-absorbing systems. The rotor’s bearing turns on DLC-coated rollers mounted on ceramic ball bearings. DLC (diamond-like carbon) has a hardness of 2000 Vickers, so it is several times harder than steel. This patented system needs no lubrication. In the event of violent impact, the walls of the bridge limit the radial displacement of the rotor. The axial play is held in check by special screws which prevent the rotor from contacting the bottom of the case. The transmission wheel that transfers the rotor’s energy to the mainspring is mounted using two Incabloc shock-absorbers.


Each year, Germany’s Uhren Magazin (one of WatchTime’s sister publications) presents the Goldene Unruh award (in English, the Golden Balance Wheel award) to the best watches in the world. For 2009, the CFB A1000 earned the Goldene Unruh award for technical achievement.

What’s missing from this picture, you ask? How about an actual watch you can wear? This brings me to the main point of this article: the new Patravi EvoTec DayDate. When you see it, the first thing you notice is the cushion shape – this is new for a watch in the Patravi line. The case measures an impressive 44 x 44.5 x 14 mm.


Beyond presence on the wrist, the EvoTec DayDate offers a clear, uncluttered, and novel dial layout. There’s a large date (or perhaps I should call it an extra-large date) at 11, a day indicator at 9, and subsidiary seconds at 6. This watch is as legible as a stop sign. The day and date displays are achieved by means of a module developed in-house and added to the CFB A1000. In this new form, the movement bears caliber number CFB A1001.


The EvoTec DayDate is available in stainless steel with a rubber bezel and a black and anthracite dial priced at SFr. 14,500, and in 18K rose gold with a brown dial priced at SFr. 35,500. Both versions come on a calfskin strap with a deployant buckle.

When the CFB A1000 movement was introduced last year, it received less attention than its innovations warranted. That is perhaps understandable given that enthusiasts could not strap one to their wrists. Now that the movement is loose in the wild, it deserves a second look.

You can read more about the EvoTec DayDate and the CFB A1000 at Carl F. Bucherer’s official web site.

Facts & Figures: Patravi EvoTec DayDate

Reference number, stainless steel: 00.10625.13.33.01
Reference number, rose gold: 00.10625.15.93.01
Model name: yes, DayDate is written as one word
Movement: automatic, Manufacture caliber CFB A1001, diameter 30 mm, height 6.1 mm, 31 jewels, power reserve 55 hours
Functions: large date display, weekday display, small seconds
Case: stainless steel, rubber bezel, screw-down crown, sapphire crystal with anti-reflective coating on both sides, caseback with sapphire crystal, water-resistant to 50 m
Dimensions: 44 x 44.5 mm, height 14 mm
Strap: calfskin, folding clasp

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