An Engine In A Crystal Shell? MB&F Introduces The HM9-Sapphire Vision
5 min read
If you know anything about MB&F - a brand that creates crazy objects, you know they can go above and beyond to create more for Geneva Watch Days 2023. Horological Machine N°9, also known as HM9 "Flow," was first displayed in 2018 as a tribute to the great automobile and aircraft designs of the 1940s and 1950s. The outcome was a unique example that reflected the flowing, aerodynamic lines of the time.
MB&F creator Maximilian Büsser called the HM9's engine "the most beautiful movement we've created to date" despite its startling exterior. What other sensible course of action could be followed but to surround the HM9 engine in a transparent sapphire crystal shell? The HM9 'Sapphire Vision' versions, also known as HM9-SV, were born as a result.
A curved bubbled, and precisely fitting three-part sapphire crystal and precious metal outer hull is sealed using a specialized blend of a patented three-dimensional gasket and a high-tech compound bonding method. Data is channeled into a differential by two completely separate cantilevered balances, which unites two heartbeats into a single coherent time-pulse. The energy and information current from the engine is effectively turned via a 90° angle by ultra-precise conical gears to supply the time display on a sapphire crystal dial with Super-LumiNova markings.
Propellers are twin turbines that spin freely on the reverse, co-axial beneath each of the balances, waiting for someone to start a different kind of exploration. Following the initial HM9 Flow 'Air' and 'Road' editions' conquest of the land and the sky, HM9-SV transports us to the ocean's depths, the last place on Earth where a wealth of hidden secrets still exists. An Atlantean exploration ship sits in front of you, propelled by a diverging technology that is both familiar and foreign to our eyes.
Externally, the HM9-SV's lines float over the design of its predecessors with the designations Road and Air. Although the hydro-governed objectives allow HM9-SV to adopt a more forgiving attitude to the acute inward angles and parabolic curves of the earlier Flow versions, the laws of fluid dynamics continue to dominate its design. Technically, the revised measurements were required to take into consideration the unique characteristics of sapphire crystal, which, despite being exceedingly hard, can fracture violently under pressure as opposed to a metal, which would merely distort. The HM9-SV's smoother contours minimize possible mechanical weak points while also enhancing the look of an ocean dweller.
The HM9 engine disregards movement-building conventions in order to continue the pathways set forth by the engines of Horological Machines N°4 and N°6. The dynamic outer case of this three-dimensional assembly of wheels, gears, plates, and bridges, a beating union of mechanical viscera and endoskeleton in a crystalline body, takes on surprising shapes.
Although a 2.5Hz (18,000vph) traditional balancing frequency may seem rather antiquated in a contemporary timekeeper, the sensitivity to shock associated with a lower beat rate is accounted for by using two balances rather than one. According to statistics, two identically calibrated systems provide a better-averaged reading than one system alone, which could produce abnormal readings due to a variety of factors.
The HM9-SV versions have a new shock-absorbing technology that uses helicoidal springs between the movement and the casing to significantly lessen sensitivity to shocks. The springs have great elasticity and little lateral displacement since they are laser-cut from a solid tube of polished stainless steel.
A planetary differential, the movement's gearbox, averages the time measurement from the two balances of the HM9 engine and then outputs a final reading to be displayed on the dial with a perpendicular orientation. The original HM9 Flow partially displayed this intricate mechanical calculation by covering each balance with a sapphire crystal dome and mounting a magnifying pane above the planetary differential to visually emphasize the significance of its chronometric function.
It was necessary to develop novel techniques to enclose the external sapphire crystal components in a single watertight container. When the tripartite casing was put together in the first HM9 Flow, a patented three-dimensional rubber gasket was already utilized to assure water resistance. The 3-D gasket is still there in HM9-SV, but a high-tech bonding substance that was perfected through an internal procedure involving a vacuum and high temperature is what fuses the sapphire crystals with the iron frame. The end result is a seal that can withstand 3ATM (30m) of water pressure even though the sapphire components and the 18K gold frame's simplistic design have virtually undetectable seams.
Where did this vision come from?
One of the hardest minerals known to man is corundum, which is more widely known as sapphire crystal when it is in its gem-quality form. Only a few other substances are harder than corundum, including the diamond (crystalline carbon), which is classified at 10 on the Moh's scale whereas corundum is classed at 9. Due to their exceptional hardness, sapphire watch crystals are virtually scratch-proof, offer the best long-term legibility and material integrity, and are more prestigious than the two most popular sapphire watch crystal alternatives (transparent polycarbonate and regular silicate glass).
The HM9 engine was created after three years of development, using only internal resources and the knowledge gained from MB&F's 20 various movements to date.
The mechanical pedigree of the HM9 engine will be familiar to long-time tribe members of the MB&F. Even though it has a very different visual shape, its double-balance system with differential is related to the same mechanism in Legacy Machine N°2. HM9 is jubilant in its appreciation of expressive design, in contrast to LM2, which focused on design purity and the hallucinogenic impact of its suspended oscillators.
The knowledge obtained in developing Legacy Machine Thunderdome has helped the MB&F team make considerable strides in chronometric regulation approaches since that time. Thus, HM9-SV gains from a few more years of specialized experience in this field. This advantage is negligible in terms of time, but immense in terms of savoir-faire.
