For a long time, watchmakers have been working hard to protect the clock movement from magnetic fields. But with the advancement of technology, the visionary minority has found a way to turn magnetism into advantage. In this two-part series, we will unveil the love-hate struggle between watchmaking and magnetism.
Piaget Emperador Coussin XL 700P concept watch, Lip Nautic-Ski watch and IWC engineer automatic watch
Although invisible and intangible, the influence of magnetic force on the precision clock adjustment mechanism always exists. At first, watchmakers rarely paid much attention to magnetic problems, because early portable instruments themselves were not precise, and any deviation caused by the damage of nearby objects was unlikely to attract attention. From 1675 to 76, Christiaan Huygens invented a hairspring, and the accuracy of pocket watch timing ushered in flying. It was not until the early eighteenth century that the application of steel hairsprings made the effect of magnetic phenomena on the normal operation of mechanical movements manifest in a quantifiable way.
Early antimagnetic alloy
In the age of enlightenment, only sailors noticed the influence of the guide on marine astronomical clocks and other deck clocks. The latter two are delicate and fragile, and must be protected from moisture, so the sailor stored it with another equally important and delicate device, the compass, for the first time at sea, which made the problem even more prominent. The watchmaker quickly realized that, as with temperature changes, magnetic forces can misalign the carefully adjusted clock mechanism, whether it is stored in the narrow space of the officer’s cabin or on the deck next to the compass, the final solution is to use the astronomical clock Keep it separate from the compass. However, the wheels of history are rolling forward, and the global industrialization wave is intensifying. By the mid-nineteenth century, electric motors had expanded to various uses and equipment. In order to maintain the accuracy and reliability of the clock, the watchmaker must come up with a low-cost method to effectively shield the magnetic field from the damaging effects of the movement.
Omega Marine Astronomical Clock
By the 1930s and 1940s, most watches were equipped with bimetal balances and blue steel hairsprings, both of which were easily magnetized. One solution is to replace traditional steel with new alloys (which are less sensitive to magnetic fields) to make certain parts. The development of Ferro-nickel Alloys is the first step in the right direction. Although it is not completely diamagnetic, iron-nickel alloys have the advantage of restoring regulation performance away from the magnetic field. The reason is simple. The alloy is not magnetized. However, some wristwatches are exposed to strong electric or magnetic fields, and more advanced solutions must be found.
IWC Engineer Automatic Watch
IWC Advertising for Engineer Watches, 1964
Looking for a solution
During this time, watchmakers observed that movements equipped with beryllium bronze (Glucydur) balances and iron-nickel balance springs needed more complete protection in certain environments, such as cockpits, electric locomotives, or factories using a large number of electric equipment. They also noticed that watches with dust caps are not as easily magnetized as watches without protection. This has prompted some brands (IWC pilots and engineers, Rolex Milgauss, Omega Ironmaster) to rely on the soft iron inner shell design to create professional timepieces that can withstand magnetic fields of up to 1,000 Gauss. This inner shell (or Faraday cage, considering that the dial is also made of soft iron) can effectively isolate the stainless steel mechanical parts and ensure accurate timing even when exposed to a strong magnetic field environment.
Rolex Ref.6543 Oyster Perpetual Milgauss watch, produced in 1955
Omega Ironmaster CK2914 watch
If you can’t beat
From the 1950s to the 1960s, these watches reached their peak. During the same period, some brands began to turn their attention to motor cores, and Mallory and Co. Inc. invented the coin cell battery to make this innovation possible. The main difficulty at the time was not how to create a watch powered by electricity, but to provide it with a lasting, and more importantly, autonomous power source. Attempts have been made: the first example is said to be a pocket watch, produced around 1910, but only at the prototype stage. It wasn’t until the mid-twentieth century that the advent of zinc-mercury batteries made it possible to conceive small, autonomous power equipment. In an article in the Journal Suisse d’ Horlogerie published in October 1955, André Beyner introduced a wristwatch driven by a conventional mechanism combined with a miniature motor. According to André Beyner, this watch has been in operation since December 1953.
How Hamilton Electric Watches Work
Soon after, in November 1956, a French company specializing in electric and electromagnetic clocks Léon Hatot (brand name ATO) released an electric watch at the annual meeting of Société Française de Chronométrie. Hatot’s watches are equipped with early transistors and Mallory zinc-mercury batteries. The seeds it sowed quietly took root in the United States and sparked a revolutionary storm. In January 1957, Hamilton, an American watch brand based in Lancaster, Pennsylvania, launched the first series of electric watches (regulated by electromagnets)-codenamed Project X. The famous Ventura watch is Developed from this. Today, Ventura is still one of Hamilton’s main collections, and now Ventura watches are driven by quartz movements.
Lip Nautic-Ski watch
The French company Lip is not far behind. In December 1958, Lip launched the R27 watch, followed by Nautic-Ski, which originated from a project launched ten years ago. At about the same time, Elgin, another American company, joined in. The sales war has begun. This will be one of the most prosperous periods of mechanical watchmaking, from project establishment to research to release. Finally, the Longines Conquest Electric Calibre 400 was born in 1962.
Love and hate are intertwined with watchmaking and magnetic force (Part 2)