Max Büsser and his Friends (with a capital F) tackled a long-standing horological challenge with the MB&F Legacy Machine No. 2. The retro-futuristic LM2, which debuted last year and is now being delivered to grateful collectors across the globe, is the end result of the MB&F team’s deliberate decision to join the tiny club of watchmakers who have created timepieces with dual regulators linked to a single differential.
Horology students in 1930s Switzerland crafted a few pocket watch examples–possibly ten in all–of timepieces powered via dual-regulators and one differential. Eighteenth and nineteenth-century watchmaking luminaries Ferdinand Berthoud, Abraham-Louis Breguet and Antide Janvier each created double regulator timepieces. But while Berthoud averaged his two regulators via mechanical means not unlike the LM2, Janvier and Breguet utilized the phenomenon of complementary vibration frequencies, or resonance, to average their watch regulators.
Today you can spot more than one balance on only a few single-movement watches, and nearly all rely on resonance to integrate two regulators. The F.P. Journe Chronomètre à Résonance, as its name explains, does not utilize a mechanical differential, for example. Watchmaking legend Philippe Dufour is likely the only other watchmaker in recent years to create a wristwatch with a plan most similar to that utilized by MB&F for the LM2. Dufour’s 1996 Duality is considered by many to be the first wristwatch using double balances coupled with a differential. (Both Greubel Forsey and Roger Dubuis also make wristwatches with differentials.) It was Dufour’s watch that prompted Busser to design the LM2 (See our Q&A with Busser on page 73 for more about his relationship with Dufour.). He again collaborated with watchmaker Jean-Francois Mojon, whose team at Chronode worked with MB&F for this model and the 2011 MB&F Legacy Machine No. 1, to make LM2 and to place its planetary differential prominently at the 6 o’clock position. But to make the differential even more prominent, MB&F raised it above the dial and supported it with a highly polished bridge that itself is inset with three large red jewels.
Those balances
Yet to many, that very visible differential, which is technically the focal point of the watch’s regulation, may just become the object of a second glance. Indeed, after seeing the Dufour Duality, Busser vowed to expose the beauty of the dual balance on a dial rather than via a clear case back as Dufour had done.
“I thought, ‘One day I will need to create a movement based on the same principle, but I want to see the balance wheels working in full view, not hidden behind,’” says Busser.
One’s first look at the LM2 dial will undoubtedly focus the eyes on the spectacular flying balances, each identical and each dramatically suspended over the pure white lacquer dial. If you recall the LM1, you might remember that the balance on that watch is also suspended high over the dial, rotating at a languorous 18,000-bph. On the LM2, MB&F essentially doubles that visual effect by suspending two equally slow-beat, custom-made balances over the dial and the aforementioned differential. Both balances are identical, each featuring a Breguet overcoil and inset with four functional timing screws. According to MB&F, the distance between the wheels has been carefully calculated to avoid resonance.
The resulting 44mm watch is, like the LM1, a healthy reminder of the past and a playful glimpse into the future. On its debut, that first MB&F Legacy Machine was a clear break from Busser’s decidedly futuristic Horological Machines, which first debuted in 2007.
Just as the watch’s slow beat (with its two balances) offers a doubled reminder of so many early mechanical pocket watch regulators, LM2’s three-dimensional mainplate/dial architecture recalls the freedom today’s inventive watchmakers enjoy with the ability to utilize modern metal-working techniques. Indeed, the sculpturally curved arms that suspend those balances require more than the ‘typical’ wire electro erosion, according to MB&F. The company’s component makers (led by Benjamin Signoud at AMECAP) must instead create a wholly new electrode that has been shaped to the form of the cutout section of the LM2 bridges.
As the LM2’s special-cut bridges betray MB&F’s modern capabilities, the gilt-edged hour-minute dial recalls the detailing so often seen on historical pocket watches. The dial material is white stretched lacquer that is applied and heated repeatedly in layers, causing the material to spread out over the slightly curved dial. The 18-karat gold hands are blued and also slightly curved to match the dial’s shape–and to provide a clear historical reference to centuries-old techniques.
That historical fidelity extends to the traditionally wide spaces between the bridges and between the bridges and the case, most easily noted via the un-historically accurate clear sapphire caseback. Noted independent watchmaker and MB&F Friend Kari Voutilainen supervised the finishing on all bridges and plates, especially the mirror-polished and beveled angles, in order to retain the style and depth seen on the best of century-old pocket watches. The LM2 is being made in red and white gold as well as in a limited edition of eighteen models in platinum that feature a blue dial.