To be presented at Baselworld 2011, the Maurice Lacroix Masterpiece Roue Carrée Seconde features a pair of rotating, enmeshed square wheels on the dial. Conceived by watchmaker Michel Vermot, who is now head of Movement Development at ML, the wheels are made by LiGA technology, a photolithography technique also used to make silicon parts for movements.

This is the first time square wheels have been used on a production watch. According to ML, “The square wheel, whose corners and contours mesh with the same precision as its circular counterparts, is activated by a toothed clover-leaf wheel and turns continuously to create an extremely dynamic visual effect.” Click here to see an animation illustrating the motion of the square gear on the dial. The watch shown in the animation is the Masterpiece Regulateur Roue Carrée launched in 2010, not exactly the same but identical in turns of gear motion. 

– SJX

Technical Information

Maurice Lacroix Masterpiece Roue Carrée Seconde

References: MP7158-SS001-900 (black) MP7158-SS001-901 (Rhodium)

CASE:

–                      Steel, Φ 43 mm, satin-brushed and polished finish

–                      Domed sapphire crystal with anti-reflective coating on both sides

–                      Screwed case back with wide sapphire crystal

–                      Water-resistant to 50 m / 5 atm

– In keeping with the Masterpiece Régulateur Roue Carrée (*) design, the dial has been created on the main plate of the movement itself and is decorated with a large “Grand Colimaçon”

– The square wheel and clover leaf mesh to transfer power with the same precision as the cogs in their circular counterparts; in addition the wheel is used to indicate the seconds

– The hours and power-reserve indications are engraved on the main plate

– Dial available in black or rhodium

– The square wheel and clover leaf are highlighted by a circular opening on the movement main plate itself, decorated with a sandblasted background.

(*) Limited Edition launched in 2010

HANDS:

–                      Trailing square wheel for the seconds display, circular satin-brushed finish upper part and polished circumference, seconds pointer coated with white C1 Superluminova (blue luminescence)

–                      No visible rotation axis

–                      Diamond-polished and faceted hours and minutes hands, coated with white C1 Superluminova (blue luminescence)

–                      Diamond-polished and faceted power-reserve hand

STRAP / BRACELET:

–                      Large-scale black crocodile-skin strap, lined with black calfskin and black over-stitching

BUCKLE:

–                      Folding steel clasp with push buttons

–                      Satin-brushed and polished finish

MOVEMENT:

–                      ML 156 mechanical movement, hand-wound

–                      Developed in collaboration with HE-ARC, manufactured and assembled by Maurice Lacroix

–                      Design patented (square wheel / clover leaf) 

Functions:

–  Hours and minutes indicated by central hands

–  Small-second display by square wheel at 6 o’clock

–  Power-reserve hand at 3 o’clock

VIBRATION:                 18,000 vph, 2.5 Hz

POWER RESERVE:   45 hours          

JEWELS:                      34                    

ADJUSTMENTS:         5 positions after full winding and after 24 hours 

DECORATION:            Grand Colimaçon, rhodium finish Update: This video shows how the square gear works. It does not show the exact same model but illustrates the principle well.