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The MB&F Legacy Machine 1 “Longhorn” Unique Piece (Live Pics)

A ghost from the Legacy Machine 1's past will reappear at auction to mark its tenth anniversary.

| By Rebecca Doulton | 4 min read |
MB&F Legacy Machine 1 Longhorn Unique Piece

As many will recall, the Legacy Machine 1 of 2011 was the foundation piece for the Legacy Machine collection that marked a radical departure from MB&F’s retro-futuristic vessels. Designed to celebrate the great innovators of watchmaking with a signature MB&F three-dimensional kinetic twist, the Legacy Machine had a traditional round case, white lacquered registers with Roman numerals and a mesmerising, monumental balance wheel suspended in the middle of the dial. The attributes of the Legacy Machine 1 would become the blueprint for an expanding dynasty of LM watches with ever-increasing complications. Then, in 2017, just six years after its debut, MB&F staged the swan song of its Legacy Machine 1 with a final 18-piece edition in steel. Well, at MB&F, the word ‘final’ is not a finite as intended. Just when we thought the LM1 had disappeared for good, MB&F resuscitates an LM1 prototype of 2011 to mark the tenth anniversary of the LM collection. The unique piece will be auctioned by Phillips in Association with Bacs & Russo in Geneva on 7 November 2021, with a significant portion of the proceeds donated to Save the Rhino International. If you’re in town for the Only Watch auction on 6 November and don’t manage to get your hands on MB&F’s HM10 Panda, you can always try again and bid for this one-off LM1 “Longhorn” prototype the following day. 

The LM1 Final Edition in Steel


With all its stock of LM1 editions depleted, MB&F decided to rescue an original prototype of the LM1 and dust it off for the tenth-anniversary commemorations. This is not the first time MB&F resuscitates a prototype: in 2020, the HM4 Kittyhawk prototype was sold privately to a collector. However, to allow more MB&F fans the chance to bid for this unique prototype, the Legacy Machine 1 “Longhorn” is up for auction.

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MB&F Legacy Machine 1 Longhorn Unique Piece

Longhorn’s horns

The prototype became known as the “Longhorn” because of the long lugs or horns that were going to be a distinctive design element of the LM1 during the design phase in 2009-2010. However, the long horns were not ideal. A problem about where to put the spring bar, close to the case or at the tip of the lug, ended up convincing Max Büsser and Eric Giroud to settle for shorter longs. Nevertheless, Büsser is not a quitter, and the idea of long horns still appealed to him. “During one of our recent brainstorming sessions, I suddenly had the idea to drill two holes in the long horn for the spring bar – one hole at the tip of the horn and the other closer to the case – and then let the customer decide where he wants to put his strap. I don’t know why I didn’t think of this 10 years ago!”

Steel case and black sub-dials

Having recovered the original concept of long, curved lugs – a unique feature not found on any other LM1 watch – there are a couple of other attributes that make this prototype truly unique. While most LM1s were produced in gold, platinum and titanium, the LM1 Longhorn is made of stainless steel, like the LM1 Final Editions of 2017. The base plate is rhodium-plated, and for the first time in the LM1’s history, the glossy white lacquer of the sub-dials has been replaced with a shiny black lacquer that contrasts exceptionally well with the blued hands. The arched bridge spanning the flying balance wheel corresponds to the latest, more organic version of the bridge also found on the Final Edition models.

MB&F Legacy Machine 1 Longhorn Unique Piece

Like earlier editions of the Legacy Machine 1, the case, with its 44m diameter and 16mm height, has two crowns to set the independent time zones displayed on the two black sub-dials with white Roman numerals. The original vertical power display is positioned at 6 o’clock, and in pride of place is the monumental 14mm balance wheel beating at 18,000vph suspended above the dial.

The reverse side reveals the 3D horological movement developed for MB&F by Jean-François Mojon with traditional 19th-century handmade finishings overseen by Finnish watchmaker Kari Voutilainen: polished internal bevels, Geneva waves, gold chatons with polished countersinks and hand engravings. The names of both men are engraved on a bridge, and the word ‘Prototype’ is engraved on the steel bezel of the caseback.

MB&F Legacy Machine 1 Longhorn Unique Piece

The LM1 “Longhorn” will be auctioned by Phillips in Association with Bacs & Russo on 7 November 2021 in Geneva. The ‘Longhorn’ nickname of the prototype came to the MB&F team during a brainstorming session and is a direct reference to the rhinoceros; an endangered species hunted for its long horn. A significant portion of the proceeds from the auction of the prototype will be given to the London-based Save the Rhino International organisation intent on protecting five species of rhinoceros in Africa and Asia.

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