The legendary mechanical movement is re-invented

  • History / Brand
  • A history of Grand Seiko in ten chapters
May 24, 2019

This is the story of Grand Seiko. It is a story of vision, determination, commitment, innovation and, most of all, of the quiet, calm and utterly single-minded determination of two generations of watchmakers to create watches that are absolutely as good as they can possibly be. The first Grand Seiko appeared in 1960 but the story started long before and continues to unfold and gather pace today. Who knows? Perhaps the best is yet to come.

The long road to mechanical excellence

As soon as it was released in 1993, the Grand Seiko 9F quartz movement was lauded as being the ultimate quartz watch and, as such, entirely worthy of the Grand Seiko tradition. Even before, the 9F quartz caliber was released, the Grand Seiko team turned its attention to the mechanical calibers.

The positive response given to a slim mechanical model called U.T.D. (Ultra Thin Dress),  created in commemoration of Seiko's 110th anniversary in 1991, had given the team great encouragement as had the continuing success of Seiko’s mid-range mechanical calibers. The time was right to use the company’s ever increasing technological skills to create a new generation of Grand Seiko mechanical calibers. 

The 52-series used successfully in King Seiko in the 1970’s was selected as the base for the movement. Just 3.9mm in depth, it was a 28,800 bph, 8-beat movement featuring a calendar and it delivered a high precision that had won its chronometer certification from the Japan Chronometer Inspection Institution.

Making best use of the company’s very latest and most advanced manufacturing technologies, the new movement, named Caliber 4S35, was completed in 1992.

Caliber 9S5 series had a new balance wheel. The movement was beautifully finished, with a wave design on the bridge and rotors. The movement shown is Caliber 9S56 with a GMT function.

Setting new standards

The new 4S movements were carefully adjusted and met the accepted global standard for precision. 500 of these specially adjusted movements were manufactured and they were well appreciated by watch experts and Grand Seiko’s customers alike. The most important result, however, was not the positive reception that these watches received. It was that it gave the Grand Seiko team an appetite to go further. Much further. They started by setting a new standard that they thought honored the Grand Seiko tradition and then set out to create a watch that would meet it. Co-inciding with the release of the 9S caliber, the new Grand Seiko standard was published in 1998 and called for an average daily precision rate of -3 seconds to +5 seconds, 6 testing positions and 17 testing days, each of which was higher than the accepted global standard. These were the extremely demanding standards that Caliber 9S, the new mechanical movement developed exclusively for Grand Seiko, had to meet.

To achieve this new Grand Seiko standard required the creation of a completely new caliber and new design and manufacturing techniques were deployed to make it possible. The caliber was designed using a CAD-CAM system developed in-house allowing 9S to be the first caliber to incorporate its advantages. Studies on new gear shapes and simulations of gear trains were conducted and compared to past design materials, and by employing this data, the Grand Seiko team was able to make rapid progress in the production of prototypes. With the invention of new alloys for the springs, the development of a new balance wheel and the introduction of a special inner edge curve in the configuration of the balance spring, Caliber 9S was able to meet the new Grand Seiko standard and to deliver a level of precision that was truly worthy of the Grand Seiko name.

The contemporary design, 1998
Taking the Grand Seiko design a step forward towards the future and using Grand Seiko’s Zaratsu polishing techniques, the curved surfaces were honed to a brilliant, distortion-free surface.

In November 1998, the first two watches carrying the completed 9S movement were launched. It was a landmark moment and ushered in a new era for Grand Seiko.