De Bethune DB29 Maxichrono Tourbillon Limited Edition

Established by David Zanetta and Denis Flageollet, the Geneva based watch manufacture De Bethune creates exceptional mechanical timepieces and complications inspired from the horology creations of the age of enlightenment.

De Bethune timepieces incorporate new technologies and materials to which the fundamental calculations and principles of conventional mechanics have been applied. The various innovations emanating from the De Bethune laboratory not only bear witness to these intentions; they also express the conviction that there is much unexplored territory in the field of watchmaking technology.

De Bethune has introduced many technological advances in the horology such as the patented balance-spring with flat terminal curve, balance-wheels in silicon and white gold or in titanium and platinum featuring maximum inertia for a minimum weight, as well as the development of a real tourbillon for the wrist in silicon and titanium.

This year the manufacture unveils DB29 Maxichrono Tourbillon, and exceptional patented chronograph timepiece equipped with tourbillon and packed with innovations.

The rose-gold case of the DB29 with its smooth curves features the brand’s trademark cone-shaped lugs. The double case back of this time-measuring instrument is fitted with an invisible hinge so as not to detract from its clean lines. A single push button, coaxial with the crown at 3 o’clock, operates the chronograph.

The design of the DB29 Maxichrono Tourbillon’s dial with its five central hands aims to make it easier and more attractive to read the chronograph indications by doing away with the small subdials of the conventional chronograph. The hands that give this watch its identity are designed to follow the different shapes and curves of the silver-toned dial. They are all in hand-polished steel that has been flame-blued by the company’s craftsmen, apart from the chronograph minutes hand, which is in rose gold.

This instrument measures long elapsed times with counters for 60 seconds, 60 minutes and 24 hours. The central chronograph hands are mounted on co-axial stacked wheels, a complex system that requires real technical expertise to achieve.

Thanks to the precision ensured by the De Bethune 30-second Tourbillon in silicon and titanium oscillating at a rate of 36,000 vibrations per hour – one of the fastest and lightest on the market with its 63 parts weighing a total of 0.18 grams – time is accurately measured and the maximum duration of elapsed-time measurements amounts to a generous 23 hours, 59 minutes and 59.9 seconds.

A push button at 4 o’clock opens the cover on the sapphire-crystal glass of a titanium case back to reveal the modern construction of the calibre DB2039 movement with its polished steel bridges, the tourbillon at 3 o’clock and the complex mechanism of an innovative time-measuring system featuring three column-wheels.

De Bethune total clutch system: a patented chronograph invention

De Bethune’s research and development department has announced the filing of a patent application n° CH00076/14 for the chronograph mechanism. De Bethune’s absolute clutch aims to improve the performance of chronographs by correcting the faults identified in current mechanisms.

This mechanism makes the most of the advantages of the horizontal and vertical clutch systems while eliminating their faults. It thus benefits from a marked reduction in the friction that affects the movement both when the chronograph is running and when it is functioning without the chronograph engaged.

The absolute clutch operates in a system engaging the two traditional clutch methods to allow the different chronograph counters to function semi-autonomously:

– The chronograph seconds are governed by the new absolute clutch system;

– The minutes counter is controlled by a shifting pinion;

– The hours counter is engaged by a horizontal clutch.

Three different types of clutch behind three semi-independent systems controlled by three column-wheels thus govern the different chronograph elapsed-time counters. In this way De Bethune marks a significant technological breakthrough in the history of chronographs, the result of continuous research heralded by the DB21 Maxichrono in 2006.

Technical details

Model: De Bethune DB29 Maxichrono Tourbillon, Ref. DB29RS1

Edition
Limited annual production: Only twenty will be issued in 2014

Functions
Hours and Minutes
Mono-pusher chronograph with 24-hour, 60-minute and 60-second counters
De Bethune 30″silicon/titanium tourbillon

Case
5N rose gold, round case
Diameter: 46 mm
Thickness: 11.70 mm
Attachments: cone-shaped lugs
Glass: Sapphire crystal, 1800 Vickers hardness with double anti-reflective treatment
Crown at 3 o’clock – mono-pusher button– setting in 2 positions
Push button for the double back at 4 o’clock
Back: open – sapphire crystal, 1800 Vickers hardness with double anti-reflective treatment –
De Bethune tourbillon 30″silicon/titanium 36,000 vph – chronograph calibre with hand-polished  bridges
Double back: solid with invisible hinge – 5N rose gold

Dial
Silver-toned – the architecture of the dial is constructed on different levels; some are curved to maximize the visibility
From the centre to the periphery : central hours counter – hours inner ring – minutes ring and minutes counter – outer ring with chronograph seconds indication
Hands: 5 curved central hands – hand-polished and flame-blued steel for hours and minutes hands and hours and seconds chronograph indicators – minutes chronograph indicator in rose gold

Movement
DB2039 calibre
Mechanical hand-wound movement
Functions: hours – minutes – mono-pusher chronograph with 24-hour, 60-minute and 60-second
Counters – De Bethune Tourbillon 30″ silicon/titanium 36,000 vph
Diameter 30 mm – 410 parts – hand-crafted finishing and decoration – hand-polished steel –
3 columns wheels
De Bethune absolute clutch
Self-regulating twin barrel
Silicon/white gold balance wheel – balance-spring with flat terminal curve
De Bethune 30″silicon/titanium tourbillon, 36,000 vph
Silicon escape wheel
Jewelling: 49 jewels
Frequency: 36,000 vibrations per hour
Power reserve: 5 days

Strap
Extra-supple alligator leather strap with pin buckle

Update: 31 Oct 14
De Bethune – DB29 Maxichrono Tourbillon has won the Chronograph Watch Prize in Grand Prix D’horlogerie De Genève 2014 event.