The HM9 Sapphire Vision watch fully displays the complex movement High-end watchmaker MB&F released a limited edition Horological Machine No. 9 (HM9) watch called “Sapphire Vision”, which placed the movement in a specially designed, transparent three-dimensional sapphire and precious metal case to show off the work.

In 2018, MB&F added the HM9 Flow watch to its amazing outrageous product portfolio. The HM9 has a case designed to echo the lines of classic cars and airplanes from the 1940s and 50s. It’s a bit weird, but the company is not satisfied with it, because the titanium case obscures the mechanical principles, which MB&F founder Maximilian Büsser describes as “the most exquisite movement we have created so far. “.

In order to correct this obvious shortcoming, copy MB&F proposed a sapphire frame, as the name suggests, the frame is replaced with a titanium case carved from sapphire. Such situations have been raised before, but these problems are often boxy, because although extremely hard, sapphire can crack under pressure, causing metal deformation.

In order to solve this problem and reproduce the shape of HM9 Flow, MB&F had to carry out some subtle redesigns to reduce the pressure on the case and process the sapphire crystal, and carried out about 350 hours of careful machining and polishing in the process. The movement is connected with a patented 3D rubber gasket around the movement, and three sapphire parts are fused to the metal frame using vacuum and high temperature processes, and then sealed with a special adhesive. The result is that the 52-component enclosure has 3 ATM (30 m, 100 ft) waterproof performance.

However, this situation is not so impressive. Its main purpose is to showcase the 52-jewel, 301-part manual-winding movement, which uses a single-barrel 45-hour power reserve and runs two independent balance wheels at a frequency of 2.5 Hz (18,000 bph). In a precision movement, this may seem slow, but the two balances are averaged by a planetary differential to produce a more accurate reading on the vertical dial display, while eliminating possible resonance.

In addition, there is a double spherical turbine under the movement, and there is a shock-absorbing coil spring between the movement and the casing. To produce these, MB&F used a laser to cut out the spring from a solid stainless steel tube to obtain better elasticity and limited lateral displacement.

HM9 Sapphire Vision will bring you neatness and provide four limited editions. There are two versions with an 18K rose gold frame with NAC-coated black or PVD-coated blue engine, and the other two versions have an 18K white gold frame and PVD-coated purple or red gold-plated engine. Both are equipped with a brown or black alligator leather strap and a matching red or white gold folding clasp.