Inspiration and Realization: A long childhood passion for assembling model aircraft had Maximilian Büsser's walls, cupboards and ceiling covered in small aircraft of every description. Planes were what he saw last thing at night and planes were what he saw first thing each morning.
The boy became a man, but something of the child and his planes remained, quietly waiting until…HM4 Thunderbolt!
Many boys sketch supercars and fast planes, but few have the drive and determination to make their dreams come true. Büsser created MB&F to do just that. The HM4 Thunderbolt is born of the child's fantasy and the man's tenacity.
Engine: HM4's engine was entirely designed and developed by MB&F over three years of intensive work with Laurent Besse and Beranger Reynard of Les Artisans Horlogers. Each of the 311 components were developed specifically for the Thunderbolt, no off-the-shelf mechanisms or parts were used at all due to the extreme nature of its architecture.
Two mainspring barrels connected in parallel provide 72 hours of energy, and they transfer their power to the dual jet-turbine-like indication pods (one displaying the hours and minutes, the other the power reserve) via vertical gear trains.
Visible through a shaped sapphire display panel on the top of the case, a distinctive streamlined cock supports the balance, its centre cut away to reveal as much of the oscillating wheel as possible and validating the "kinetic" in MB&F's "kinetic art".
A work of art rewards when viewed from different angles and the Thunderbolt is no exception. Turning the machine over reveals a veritable panorama of meticulously finished micro-engineering through the sapphire sections. In a playful trompe d'oeil, what at first glance appears to be a micro-rotor in the form of MB&F's iconic battle-axe is actually a bridge.
Indications: For a timepiece not developed specifically to tell the time, HM4 performs that role superbly. In fact, with its highly legible dials perpendicular to the wearer's wrist, Horological Machine No4 might be described as the perfect pilot's or driver's watch.
On the left pod, the amount of fuel in the tanks - or power reserve - is clearly indicated by a skeletonised hand echoing MB&F's battle-axe motif. On the right, hours and minutes are displayed by bold, arrow-tipped Super-LumiNova filled hands. Each of the two aviation instrument-styled dials is directly controlled by its own crown, one to wind and re-fuel the tanks, the other to set the time, which provides direct and instantaneous feedback of the action performed.
Case: Inspired by aviation, more specifically the model aircraft kits of Maximilian Büsser's childhood, the case of HM4 imparts speed, power, technology and refinement in equal measure. Visually, the case is composed of three parts: two streamlined jet-turbine-styled pods supported by a horizontal section housing the engine, which is clearly visible through transparent sapphire display panels and the central section of the case itself.
Technically there are also three main sections, but these comprise a fore section in titanium, which includes the dials and articulated front lugs; a central section in sapphire offering unprecedented 360° access to the superbly finished engine; and an aft section tapering down to the dual crowns and framing the animated balance, which is supported by an aerodynamic cock. Methods borrowed from aeronautic engineering are visible in the externally mounted screws, which provide both rigidity and watch resistance to hold the case’s three sections solidly and elegantly together.
Beginning with a solid piece of sapphire, more than 100 hours of intricate machining and meticulous polishing are required to turn an opaque block of crystal into the clear, light-filled atrium of the central case section, which reveals part of the Thunderbolt's engine and engineering details. The metal case sections are milled from solid blocks of high-tech Grade 5 titanium, which undergoes hundreds of hours of machining before polishing, masking and finally satin-finishing of the surfaces. The results speak for themselves.
The contrasts of matte with highly polished surfaces, titanium with sapphire, straight lines with seductive curves and rigid forms with articulated arms endows Horological Machine No4 with a life and vibrancy that sets it apart from anything that has ever gone before.
HM4 Thunderbolt is the quintessential machine as three-dimensional kinetic art.
Horological Machine No4 Thunderbolt – Technical Specifications
Three-dimensional horological engine developed 100% by MB&F
Manual winding with two mainspring barrels in parallel
Power reserve: 72 hours
Balance frequency: 21,600bph/3Hz
Number of components: 311
Number of jewels: 50
Hours, minutes and power reserve indicator
Hours and minutes on right dial, power reserve indicator on left dial
Separate crowns for time setting and winding
Grade 5 titanium and sapphire
Dimensions: 54mm wide x 52mm long x 24mm high
Number of components: 65
Articulation of lugs: 3°
Sapphire crystals: Five sapphire crystals: 2 x dials, 1 x central case section, 2 x display panels (top and bottom)
Strap & Buckle: Black hand-stitched calfskin strap with titanium/white gold custom designed deployment buckle attached to articulated lugs
'Friends' responsible for Horological Machine No4 “Thunderbolt”
Concept: Maximilian Büsser/MB&F
Product Design: Eric Giroud – Eric Giroud Design Studio
Technical and Production Management: Serge Kriknoff/MB&F
Production logistics: David Lamy/MB&F
Movement Development: Laurent Besse, Béranger Reynard and Patrick Lété of Les Artisans Horlogers
Movement manufacturing: Daniel Uhlmann/Azuréa Technologies, Nicolas Broquet/Broquet Décolletage, Yann Ryser/Tital
Hand-finishing of movement components: Jacques-Adrien Rochat and Denis Garcia of C-L Rochat
Movement assemblage: Didier Dumas and Georges Veisy/MB&F
Case and buckle construction and production: Jean-Pierre Kohler and Lionel Gavignet of Profusion, Martin Stettler of Stettler, Dominique Mainier and Bertrand Jeunet of G.F.Châtelain
Dials: François Bernhard and Denis Parel of Nateber
Hands: Pierre Chillier, Isabelle Chillier and Félix Celetta of Fiedler
Strap: Olivier Purnot/Camille Fournet
Presentation box: Olivier Berthon/Berthon & Co
Graphic Design - Alban Thomas and Gérald Moulière of GVA Studio
Product Photography - Maarten van der Ende
Display Architecture - Frédéric Legendre/Lekoni
Portrait Photography - Régis Golay/Federal
Webmasters - Stéphane Balet and Guillaume Schmitz of Sumo Interactive
Texts - Ian Skellern
Project Manager - Estelle Tonelli/MB&F