BIANCHET B 1.618 ULTRAFINO
BIANCHET introduces the B 1.618 ULTRAFINO, a tonneau-shaped sports watch with unprecedented levels of elegance and performance. Beating inside this timepiece is Bianchet’s first automatic flying tourbillon movement, the ultra-thin UT01 caliber, crafted from titanium and designed around the Golden Ratio (1.618).
Measuring just 8.9 mm in height and 40 mm in width, the sleek, curved tonneau case has been designed to conform seamlessly to the wrist with a 1.2 mm curvature from lug to lug.
While ultra-thin watches often sacrifice robustness, the UltraFino defies convention. It withstands shocks of up to 5,000Gs and water pressure of 5 ATM, offering a rare combination of elegance and wearability. This fusion of strength and refinement makes it an ideal everyday timepiece.
The UltraFino comes in two distinct yet equally refined versions: an open-worked model showcasing the beautifully hand-finished UT01 movement and a dial version featuring the exclusive Golden Diamond pattern, a contemporary reinterpretation of the classic Clou de Paris motif inspired by the Golden Ratio.
Both interpretations wear Bianchet’s distinctive rubber seam between the bezel and case middle, highlighting the craftsmanship expertise that defines Bianchet’s approach to horology.
The UltraFino Skeleton reveals the ultra-thin UT01 movement, an engineering marvel measuring just 3.85 mm thick and weighing only 8 grams.
One of the very few ultrathin automatic flying tourbillon movements in titanium, it is paired with a gold rotor designed with interlacing Fibonacci spirals, ensuring optimal efficiency and aesthetic harmony. Each angle and transition within the movement architecture has been sculpted to reflect the divine proportions 1.618, reinforcing Bianchet’s dedication to mathematical beauty in design.
By reinterpreting a different escapement stacking solution inspired by an old ultra-flat movement, Cal.UT01’s height was minimized while maintaining generous safety margins.
The construction of the tourbillon cage in the UT01 automatic movement was also guided by bold aesthetic and structural choices, allowing Bianchet to incorporate the elegance of a large screw balance wheel.
With a diameter of 8.90 mm (excluding screws), a frequency of 3Hz, and an inertia of 10 mg/cm², this regulating organ features excellent technical specifications. The ingenuity of its construction also made it possible to maintain a high level of shock absorption, ensuring excellent resilience within an ultra-thin architecture.
Maximizing energy efficiency in the mainspring barrel is a well-known challenge in an ultra-thin movement. Bianchet’s UT01 automatic movement has maintained a generously sized barrel by ingeniously constructing a suspended barrel. This barrel provides a power reserve of over 60 hours without compromising safety margins or shock resistance.
Similarly, the position of the gear train has been optimized to achieve greater thinness while increasing transmission stability. The alignment angles of the wheels have been calculated to neutralize torque variations as much as possible, thereby reducing differences in the balance wheel’s amplitude and ensuring optimal gear efficiency for more stable chronometry.
Bianchet’s proprietary winding and time-setting system features a fixed angular gear transmission with a 90° toothing for improved energy transfer and user comfort. The two-position mechanism includes a pivoting lever that smoothly transitions between winding and time-setting functions, depending on the position of the winding stem.
The new Bianchet automatic caliber is distinguished by an exceptional level of finishing, enhancing depth and light play through a striking contrast of textures that define its open-worked architecture.
The main plate and bridges, crafted from titanium, feature a marriage of soft sandblasted finish that subtly absorbs light with finely satin-brushed surfaces, elevated by delicately hand-polished bevels that catch and reflect every glimmer.
This subtle dialogue between matte and polished surfaces gives the ultra-thin movement a remarkable three-dimensional presence in an ultra-flat architecture, revealing the full complexity of its construction. The wheels, adorned with a circular satin-brushed finish, contribute to this dynamic, creating a fluid and refined visual effect that draws the eye to the heart of the mechanism.
Every detail is executed with absolute precision, down to the carefully polished screws, achieving flawless brilliance. The tourbillon cage, entirely beveled by hand, exemplifies this artisanal commitment, highlighting the finesse and elegance of the mechanism. The solid gold rotor showcases a refined contrast between circular satin-brushed surfaces and sandblasted zones. At the same time, the polished bevels accentuate each curve with precision. When the rotor is in motion, this interplay of finishes creates a captivating dance of light.
While integrated metallic bracelets are often associated with round watches, Bianchet takes a pioneering step by introducing one to a tonneau-shaped case. The UltraFino’s fully integrated titanium bracelet enhances the watch’s fluidity and ergonomics, following the contours of the curved case to create an unbroken line of sculptural elegance.
The bracelet’s architecture is not only about aesthetics; it also ensures structural resilience and a supremely comfortable fit, setting a new standard for what an integrated tonneau sports watch can be.
A vulcanized natural rubber strap with a titanium deploying buckle offers an alternative styling option, enhancing versatility while maintaining a perfect seamless integration with the case’s rubber seam.
Model: Bianchet B 1.618 Ultrafino
Case
Case in grade 5 titanium with natural vulcanized rubber
Dimensions: 40 mm x 47.39 mm x 8.9 mm
Shock resistance 5000G
Water resistance: 5 ATM (50 meters)
Movement
Automatic movement UT01 in grade 5 titanium and gold
Flying Tourbillon in grade 5 titanium
Finished and assembled by hand
Strap
Strap 1 in grade 5 titanium
Strap 2 in natural vulcanized rubber with titanium folding clasp
Guarantee
5 years
Price
B 1.618 UltraFino Dial: 55 500 CHF (excl. taxes)
B 1.618 UltraFino Skeleton: 60 500 CHF (excl. taxes)
