MB&F Legacy Machine Perpetual EVO is the sportier version of the award-winning LM Perpetual Calendar watch created in collaboration with Stephen McDonnell.
Designed to meet the specifications of an outdoor sports watch, this model features a 44mm diameter case and a specially developed monobloc shock-absorbing system known as “FlexRing”. The LM Perpetual EVO was first launched in zirconium with three options of PVD/CVD dial-plate colour, including atomic orange. A grade 5 titanium edition follows in 2021, with a green CVD dial plate. All editions feature a closely-fitted, integrated rubber strap.
Although the 44mm diameter is unchanged from its 2015 iteration, the new EVO case design features a no-bezel construction, with the domed sapphire crystal fused directly to the case. The increased openness of this design highlights the equilibrium between the legibility of LM Perpetual EVO’s calendar indications and the cinematic play of the engine components — surmounted by the iconic MB&F hovering balance wheel.
This expansive new presentation of the LM Perpetual Engine was no simple design reconfiguration. New geometries for the sapphire crystal had to be calculated, achieving the mechanically opposing aims of maintaining structural strength and decreasing its height-to-diameter ratio. Freeing LM Perpetual EVO from the bezel also necessitated the use of a sophisticated thermal bonding system between the sapphire crystal and the case.
The previously circular pushers for adjusting the perpetual calendar have been enlarged into double-sprung oblong actuators, boosting the tactile comfort and ease of adjustment. For the first time in any MB&F creation, the LM Perpetual EVO is rated at 80m of water resistance, enabled by its screw-down crown.
A small, but essential, detail of implementing a screw-down crown is the débrayage of the winding stem, disengaging the crown from the winding mechanism when it is pushed in and tightened, which eliminates the chance of manually over-winding the mainspring barrel.
An additional new element of the LM Perpetual EVO is the FlexRing: an annular dampener fitted between case and movement, providing shock protection along the vertical and lateral axes. Machined from a single block of stainless steel, the dampener imparts exceptional robustness to the timepiece.
Legacy Machine Perpetual EVO was first launched in three variations of 15 pieces each in zirconium with orange CVD dial plate, blue CVD dial plate or black PVD dial plate; and is now available in titanium with a green CVD dial plate.
Technical details
Model: MB&F Legacy Machine Perpetual EVO in Titanium
Engine
Fully integrated perpetual calendar developed for MB&F by Stephen McDonnell, featuring dial-side complication and mechanical processor system architecture with inbuilt safety mechanism. Manual winding with double mainspring barrels. Bespoke 14mm balance wheel with traditional regulating screws visible on top of the movement. Superlative hand finishing throughout respecting 19th century style; internal bevel angles highlighting hand craft; polished bevels; Geneva waves; hand-made engravings.
Galvanic black dials with both SLN numerals and hands(except for the leap year and power reserve)
FlexRing: an annular dampener fitted between case and movement, providing shock protection along the vertical and lateral axes.
Screw down crown
Power reserve: 72 hours
Balance frequency: 18,000bph/ 2.5Hz
Number of components: 581
Number of jewels: 41
Functions/indications
Hours, minutes, day, date, month, retrograde leap year and power reserve indicators
Case
Material: Zirconium or Titanium
Dimensions: 44 x 17.5mm
Number of components: 70
Water resistance: 8ATM / 80m / 270 feet
Sapphire crystals
Sapphire crystals on top and display back treated with anti-reflective coating on both faces
Strap & buckle
Rubber strap with titanium folding buckle