Going with the Horological Machine N°9 Flow

Melvyn Teillol-Foo

MB&F Aerodynamic Horology

HM9 Flow

With the Horological Machine N°9 ‘Flow’, Max Busser & Friends take us back to the post-war 1940s and 50s, way before wind tunnels and CAD software determined the shape of things. Then, if it looked good, it was good…

HM9 on the wrist

MB&F celebrates the era of wild inventors, brave engineers and bold designers who followed only their instincts and aesthetic sense to create some of the most beautiful automobiles and airplanes ever crafted. With flowing lines and generous curves, these were machines that looked fast even when standing still. That golden era is the origin of Horological Machine No.9, also known as HM9 ‘Flow’.

HM9 Flow

Max Busser and his friends recall those beautiful man-made objects as epitomised by automobiles like the Mercedes-Benz W196 and 1948 Buick Streamliner. The aviation industry chipped in with aircraft such as the sleek-bodied, snub-nosed De Havilland Venom that patrolled Swiss airspace for 30 years.


The case for the HM9

HM9 Road Edition

The HM9 case is reminescent of an old-style jet engine with a geometrically complex combination of milled sapphire crystal and grade 5 titanium, the latter with alternating polished and satin finishes. The initial design was deemed “impossible” by their manufacturing Friends.

HM9 Profile

They had to wait a while until new manufacturing standards and techniques caught up with the specifications for extreme curves and acute angles.

HM9 Air

We have previously reported MB&F watches HM8 [HERE] and HM7 [HERE]

Other cases, such as the undulating shell of the HM6 Space Pirate, were geometrically complex, but their maximum height differential (the vertical distance between contiguous points) remained within 5mm. With HM9, that differential doubled, creating radical curves that give the case its highly tactile presence.

HM9 rear

These steep curves are paired with slim bands of mirror polish and wider swaths of satin finish, raising issues when finishing tools of a fixed diameter had to somehow navigate the narrow channels of the case exterior. Adjusting the placement of different finishes in order to accommodate the finishing tools was not an option, as this would have diminished the full-volumed aesthetic of HM9.

HM9 Back

The dramatic geometry of Horological Machine N°9 ‘Flow’ could only be supported by equally dramatic contrasts of finished surface, so manufacturing conventions evolved to meet the demands of HM9.

HM9 on the wrist

Because of the proportions of the curves on the HM9 case, it was essential to control the overall size. Horological Machine N°9 ‘Flow’ measures 57mm at its widest point and requires a highly compact yet robust engine. The key to making it to actual production is the spatial efficiency of its engine.


The engine for the HM9

HM9 engine and transmission

Inside the curvilinear case, an equally complex manual winding movement was developed after three years of effort, with the accumulated experience of their previous 14 movements. They kept the layout of the Legacy Machine line with the two lateral pods, each housing a flying balance wheel and independent regulating system. You can see these under sapphire crystal domes. The balance wheels turn at a leisurely and visible rate of 2.5Hz (18,000bph). When you pay this much for a watch, you want to be able to see it doing stuff!

HM9 engine

The central “gearbox” of the HM9 engine is visible through a third pane of sapphire crystal. It allows sight of the planetary differential that averages the output of both balance wheels to provide one stable reading of the time. The dial indicating hours and minutes sits perpendicular to the rest of the HM9 engine and is driven by conical gears that ensure precise engagement.


The cost for the HM9

HM9 ‘Flow’ debuts in two titanium editions limited to 33 pieces each:

HM9 Air Edition Front

– the ‘Air’ edition comes with a dark NAC coated movement and aviator-style dial


HM9 Engines


HM9 Road Edition Front

– the ‘Road’ edition has a matte rose gold plated movement and classic speedometer-style dial.

Retail price is CHF 168,000 + VAT (USD 182,000 + tax).

HM9 on-the-wrist


Author’s Biography: Melvyn Teillol-Foo (MTF)

Dr Melvyn Teillol-Foo is a contributor on AlphaLuxe web-zine.
He was also CEO of PuristSPro.com horology discussion fora. He blends his scientific medical objectivity from the pharmaceutical industry with purist passion, in his musings about watches, travel, wine, food and other epicurean delights.
His travelogue ‘Lazing’ and feasting ‘Grazing’ series of articles have now passed into “mythic legend” on the original ‘ThePuristS.com’ website. Those were the halcyon days when he was “rich and famous” that he remembers with bittersweet fondness.

Dr Teillol-Foo is a quoted enthusiast on the watch industry, appearing in feature articles and interviews by Wall Street Journal, International Herald Tribune, Sunday Times (London), Chronos (Japan), Citizen Hedonist (France) and other publications. He has authored articles for magazines like International Watch (iW) – both U.S. & Chinese editions, ICON (Singapore), August Man (Singapore), Comfort (China) and The Watch (Hong Kong).


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