MB&F reinvents the Perpetual Calendar
MB&F presents a new edition of the Legacy Machine Perpetual at Dubai Watch Week 2016, while Stephen McDonnell, master watchmaker, narrates the story behind it
First launched in 2015 in red-gold and platinum editions, the LM Perpetual is now also available in two white-gold editions: a limited edition with purple face, and a non-limited edition with grey face.
MB&F and independent Irish watchmaker Stephen McDonnell have completely reinvented the perpetual calendar in the Legacy Machine Perpetual, which features a visually stunning in-house movement – developed to eliminate the drawbacks of conventional perpetual calendars.
The new complication can be fully appreciated dial-side – one of the many benefits offered by the new movement, controlled by a mechanical processor (patent pending). LM Perpetual features a fully integrated 581-component calibre with a revolutionary new system for calculating the number of days in each month.
One of the great traditional complications, the perpetual calendar calculates the varying numbers of days in each month − including the 29 days in February during leap years. But a few drawbacks are that dates can skip; they are easy to damage if adjusted while the date is changing; and the complications compromise of modules powered by base movements.
The purpose-built movement of LM Perpetual has been designed for trouble-free use: no more skipping dates or jamming gears, and the adjuster pushers automatically deactivate when the calendar changes, eliminating that problem.
Traditional perpetual calendars use a 31-day month as the default and fast-forward through the redundant dates during changeovers. This means that a traditional perpetual calendar changing from February 28 to March 1 scrolls quickly through the 29th, 30th and 31st to arrive at the 1st.
LM Perpetual uses a “mechanical processor” that utilises a default 28-day month and adds extra days as required. Therefore, each month always has the exact number of days required; there is no fast-forwarding or skipping of redundant days.
Another major change is that while the leap year can only be set on traditional perpetual calendars by scrolling through up to 47 months, the LM Perpetual has a dedicated quickset pusher to adjust the year.
Its open dial reveals the full complication and suspended balance that is connected to the escapement on the back of the movement by what is probably the world’s longest balance staff.
Using a specially developed innovative system, the subdials appear to “float” above the movement with no visible attachments, by resting on hidden studs; technically impossible in the traditional mechanisms because they would block the movement of the grand levier.
The watch’s display of the hours and minutes is nestled between the arches of the balance at 12 o’clock; day of the week at 3 o’clock, power reserve indicator at 4 o’clock, month at 6 o’clock, retrograde leap year indicator at 7 o’clock, and date at 9 o’clock.
Legacy Machine Perpetual is available in three limited editions of 25 pieces each in platinum 950 (blue face), 18k red gold (grey face) and 18k white gold (purple face); and in a non-limited edition in 18k white gold with grey face.
