Introducing the MB&F Legacy Machine ‘Split Escapement’By Sumit Nag
When MB&F first introduced the Legacy Machine side of their horological narrative with the Legacy Machine No.1 — more than the floating sub-dials and the innovative vertical power reserve indication — what was, no doubt, the visual point of focus on the timepiece, was its 14mm balance wheel held in suspension above all of the dial elements and just a hair beneath the domed sapphire crystal.
In furthering the Legacy Machine story, this concept of the balance wheel being held in suspension above the watch face was amplified in the LM No.2, purified with the LM101 and elevated with the LM Perpetual. The thing that must be pointed out about the LM Perpetual, though, is that here was the first instance in which MB&F solely presented the balance wheel on the dial side. The remaining components of the regulating assembly — palette fork and escapement wheel — were placed under the dial, visible through the caseback.
Perhaps in light of the brilliance of the newly conceptualized perpetual calendar mechanism, created by watchmaker Stephen McDonnell, his feat of having separated the balance wheel from the palette fork and escapement wheel, placing them on either side of the dial, connected by what was at that time the longest balance shaft ever used in a watch at 11.78mm, went by mentioned only as a fact and figure.
The length of that shaft — that exact length — and how it was crafted, was crucial in ensuring effective transmission of energy from the barrel to the balance wheel and thereafter the transmission of the wheel’s regulation to the going train. The slightest imbalance here would’ve resulted in a watch that looked spectacular, but kept nonsense time. This was a matter of chronometry that could’ve very easily been compromised as a result of an aesthetic decision.
This bit of triumph was no mean feat. It quite clearly deserved its own stage. And that is exactly what the MB&F Legacy Machine ‘Split Escapement’ seeks to provide.
With the dial cleared of the complexities of the perpetual calendar mechanism, now it becomes apparent that the balance wheel is quite clearly missing its partnering components. Leaving the 11.78mm balance shaft in plain sight for your jaw to drop.
This has also created the opportunity to bring back the frosted dials of the LM101 Frost, which were quite the hit with collectors. Although, where the LM 101 only had the time and power reserve indicator white lacquered sub-dials, the LM ‘Split Escapement’ has a third, date sub-dial, which can be adjusted using a pusher on the left side of the case. Cool thing about the pusher, is that it, too, has some clever innovations worked into it.
Again, this is from the one and only Stephen McDonnell, who has created a clutch system for the date pusher, such that you won’t able to manipulate the date indicator during the crucial hours when it’s getting ready to change to the next date. Essentially, the clutch disengages during these hours and renders the pusher non-functional until it’s out of the critical hours.
The watch will be produced in a 44mm white gold case, in four dial variations in frosted blue, ruthenium, red gold and yellow gold, each limited to 18 pieces.
Technical Specification: MB&F Legacy Machine ‘Split Escapement’
Manual winding movement created by Stephen McDonnell for MB&F, with the ‘Split Escapement’ mechanism; hours and minutes; date; power reserve indicator; double barrel power reserve of 72 hours
44mm x 17.5mm. 18k white gold case; water resistant to 30m
Black or brown hand-stitched alligator strap with white-gold folding buckle
Price: CHF 79,000/SDG 129,400