Bokey TimeHello everyone, this is Bokey Watch Industry. Friends who are familiar with mechanical watches should know that there is such an integrated chronograph mechanical movement that is almost universally used in entry-level Swiss chronograph watches. What is it? That’s right, it’s the ETA7750 chronograph movement.
Although ETA’s three-hand movements once had a semi-monopolistic position in the global movement market, the 7750 chronograph movement has almost a complete monopoly in market share. Friends who know about it can leave comments to share with new friends, telling them which luxury watch brands have used the 7750 movement. The predecessor of this movement was actually produced by the First Moscow Watch Factory. This movement factory went bankrupt in the 1980s after the end of the quartz crisis in the watch industry, and then was acquired by ETA. ETA also improved the movement from the original 17 jewels to 25 jewels.
So, where exactly does the ETA7750 movement excel?
First, it is an integrated chronograph mechanical movement. Here’s a piece of knowledge to share: mechanical watch chronograph movements can be divided into two types. Integrated chronograph movements have their timekeeping and chronograph functions designed as one unit – when you press the chronograph button, you can see obvious movement on the back of the movement. Split-type chronograph movements are separated; their timekeeping and chronograph functions are independent. In other words, the chronograph function of a split-type movement is just a module mounted on top of the base movement. Any basic three-hand movement can be fitted with a chronograph module to achieve the chronograph function of the watch. When you press the chronograph button, there is no movement on the back. This kind of design feels quite unimpressive, to sum it up in three words: a patchwork product.
The second advantage of the ETA7750 movement is its excellent scalability. Many derivative movement models have been developed from the 7750, such as the 7751, 7753, 7754, 7758, 7760, etc. By adding or removing components of the movement, chronograph watches with different functions can be modified. These modifications are pre-designed by the movement manufacturer, not aftermarket modifications that may affect durability. For example, Longines’ flagship model with eight hands and a moon phase, which features complex functions like an annual calendar, chronograph, and moon phase, demonstrates the strong scalability of this movement.
During the era when the mechanical watch industry was reviving, the 7750 movement was used in many excellent watches. However, the movement itself is very cost-effective. Being affordable does not mean it is not durable; it is just not overly expensive, which is understandable. After all, it would be unrealistic for a universal movement to be too pricey.
The ETA7750 movement has a beat rate of 28,800 vibrations per hour, a power reserve of 42 hours, 25 jewels, two Incabloc shock absorbers (with no shock absorber for the escapement), a indexed balance wheel, a nickel-iron-chromium-cobalt hairspring, a lever escapement, a unidirectional winding ball-bearing rotor, a single mainspring barrel, a stop-seconds function, a slow date adjustment, no anti-magnetic properties, a horizontal clutch, and a cam disc.
If “cam disc” is hard to understand, here’s a simple explanation: the development of the cam disc was to reduce costs. Compared to a column wheel, the pressing feel of the cam disc is somewhat vague – the “click” detent sensation is less distinct, but the pressing force is lighter, and it is undoubtedly durable. If there is a major drawback, it might be that it is not very visually appealing.
As for the horizontal clutch, simply put, it is slightly less durable. Moreover, when starting the chronograph second hand, two gears collide and engage rigidly, causing the chronograph second hand to have a delay or jitter. However, compared to the vertical clutch, its cost is much lower. Currently, horizontal clutches are mainly used in men’s chronograph watches. For the sake of the visual appeal of the movement’s back, the collision of the two gears still creates quite a visual effect.
Although the configuration of the 7750 movement no longer holds obvious advantages today – after all, the current pursuit is for high-end features like column wheels, vertical clutches, silicon hairsprings, and long power reserves – it has witnessed the former glory of Swiss movements. This is understandable, as various brands have gradually developed their own chronograph movements. Even ETA has launched improved versions, such as Longines’ 687 movement. However, in Guangzhou’s Zhanxi Watch City, the 7750 movement still shines brilliantly!
