Bianchet B 1.618 UltraFino

First automatic tourbillon movement by Bianchet

Ultimate ergonomics of the integrated bracelet in titanium

Movement, dial, and case designed with the golden ratio

Shock resistance of 5000 g and water resistance of 5 atm

A perfect balance of aesthetics, comfort, and resilience

Bianchet introduces the B 1.618 UltraFino, an extraordinary expression of artistry and engineering in the world of Haute Horlogerie. With its seamless integration of form and function, the UltraFino redefines the tonneau-shaped sports watch, elevating it to unprecedented levels of elegance and performance. The heart of this timepiece beats with Bianchet’s first automatic flying tourbillon movement, the ultra-thin UT01 caliber, crafted from titanium and designed around the Golden Ratio (1.618).

Balancing sophistication with technical prowess, the UltraFino merges purity of design, high performance, and an unparalleled level of comfort, making it a distinguished choice for those who seek refined horology that fits effortlessly into daily life.

Where Haute Horlogerie Meets Contemporary Ergonomics

In developing the UltraFino, Bianchet’s objective was not to make the world’s thinnest watch at all costs but to achieve a perfect balance of aesthetics, ergonomics, and resilience. The result is a sleek, curved tonneau case, measuring just 8.9 mm in height and 40 mm in width, designed to conform seamlessly to the wrist with a 1.2 mm curvature from lug to lug. This thoughtful design ensures exceptional comfort, creating an experience where the watch feels like an extension of the wearer.

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, proving that Haute Horlogerie can be technically groundbreaking and wearable daily.

An Exquisite Skeleton or an Elegant Dial—Two Expressions of Timeless Design

The UltraFino comes in two distinct yet equally refined versions: an openworked 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.

Redefining the Integrated Sport Tonneau

While integrated metallic bracelets are often associated with round watches, Bianchet takes a pioneering step by introducing one to a tonneau-shaped case—a rare and demanding feat in watchmaking. 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.

A Celebration of Proportional Perfection

True to Bianchet’s signature style, the UltraFino’s design is a direct tribute to the Golden Ratio. This mathematical principle has guided some of the world’s most outstanding architectural and artistic achievements, such as the Monalisa of Leonardo Da Vinci. The Golden Ratio, present in everything from natural formations to celestial structures, is more than a design choice. This philosophy brings balance, proportion, and a subconscious sense of perfection to every UltraFino timepiece. The interwoven Fibonacci spirals that form the rotor, the precisely calculated contours of the case, and the meticulously crafted dial elements all testify to this commitment to harmony

Fibonacci bridges

Fibonacci rotor

The movement's rear bridges echo this mathematical harmony, embodying two concentric golden circles whose proportions align with the 1.618 ratio. This aesthetic and functional structure provides full peripheral support for the oscillating weight, absorbing shocks in demanding physical conditions while maintaining the highest standards of visual elegance.

A Timeless Fusion of Art and Performance

With the B 1.618 UltraFino, Bianchet reimagines the tonneau sports watch, combining ultra-thin Haute Horlogerie, ergonomic mastery, and modern resilience. Whether in its openworked or dial version, the UltraFino represents the pinnacle of contemporary watchmaking, offering a refined aesthetic and technical excellence in equal measure.

By adhering to the principles of mathematical beauty and uncompromising craftsmanship, Bianchet redefines what an integrated tonneau sports watch can be—a timepiece as enduring as it is elegant, as sophisticated as it is strong. It celebrates proportion and sleek lines, a testament to fine watchmaking, and a bold statement of high performance.

Bianchet Caliber UT01

At the heart of the UltraFino is the Bianchet UT01, a movement that embodies the brand’s quest for technical excellence and artistic precision. It is engineered to withstand extreme conditions without compromising its refined aesthetics.

The fusion of three domains of excellence—artistry, performance, and precision—may seem like an ambitious challenge, but when executed harmoniously, it results in a true feat of mechanical engineering. Bianchet’s ultra-thin and ultra-light automatic tourbillon caliber, weighing 8 grams and measuring 3.85 mm in height, embodies this vision, marrying aesthetics, precision, and cutting-edge performance.

Mastery in Titanium and Gold

The entire movement is crafted from solid titanium, a material chosen for its noble and lightweight properties and resilience. At the same time, the gold rotor, inspired by Fibonacci spirals, ensures optimal winding efficiency with a visual elegance that is uniquely Bianchet. From the rear bridges to the peripheral rotor, every element within the UT01 caliber is designed according to the Golden Ratio, reinforcing the brand’s philosophy that mathematical harmony results in artistic beauty and mechanical excellence.

One of the rare ultra-thin automatic tourbillon movements, Bianchet's UltraFino caliber is a testament to thinness and high performance. It is achieved through a unique design approach that ensures outstanding efficiency while maintaining a high balance wheel quality factor. The tourbillon cage measures just 2.66mm in height, exceeding industry standards in functional reliability.

Engineering Challenges and the Achievement of a Collective Vision

The development of Bianchet’s new automatic movement posed multiple challenges: optimizing efficiency while maintaining an ultra-flat architecture, ensuring superior shock resistance and chronometric precision suitable for high-intensity physical activities, and preserving the refined aesthetics of Haute Horlogerie components within an extra-thin structure.

More than three years of relentless effort from Bianchet’s team of constructors, engineers, and designers led to the creation of an ultra-thin, ultra-high-performance, ultra-light, and ultra-resistant flying tourbillon movement. This exceptional caliber adheres to the principles of harmony and artistic perfection dictated by the Golden Ratio.

High-Performance Tourbillon and Escapement

The escapement architecture has been redesigned to reduce the risk of the balance wheel overbanking and optimize the vertical space occupied by the tourbillon cage. This has ensured optimal efficiency and functional safety margins that exceed industry standards.

By reinterpreting a different escapement stacking solution inspired by an old ultra-flat movement—a reinterpretation made possible and optimized through modern manufacturing techniques—the movement’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.

Energy Efficiency and Performance Optimization

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.

Haute Horlogerie Finishing

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, drawing the eye and emphasizing the geometric purity of its design. This harmonious composition gives the movement a dynamic and mesmerizing quality, where fine watchmaking meets mathematical perfection.

Through this pursuit of excellence, Bianchet upholds the noblest expression of high horology, where technical mastery and artistic craftsmanship combine seamlessly