History of Timepieces History of the Anti-Magnetic Watch

Anti-Magnetic Watches

With all the advances in modern technology, it is becoming even easier to damage a watch without even thinking that you’re damaging it. Having an anti-magnetic watch will help avoid magnetizing the movement which can cause timing issues. Magnetism shortens the spring which causes it to oscillate faster. This oscillation will then typically increase the watch’s rate, meaning it could suddenly run fifteen minutes fast per day.

What is an Anti-Magnetic Watch?

In short, an anti-magnetic watch is one that is able to run with minimal to no time deviation when exposed to a certain level of magnetic field. While most of us don’t work in a highly magnetic environment, you cellphone, computer and even speakers all feature magnets that can affect the timing in your watch. Follow along as we explore the advances in development.

Early Days of Development

When pocket watches were first being produced, our world didn’t have the need for anti-magnetic movements. There were not enough powerful magnetic forces to alter the spring. Electricity, planes, trains and cars all brought around a new magnetic field and people were noticing it on their watches.

Vacheron Constantin anti-magnetic pocketwatch

In the 1840s, Vacheron Constantin was one of the first manufactures to experiment with anti-magnetic features. Around the same time, Breguet was experimenting with glass balance springs while others tested gold. As you may have guessed, these materials were too delicate in the movement and couldn’t maintain accuracy or be produced on a large scale.

Charles-Auguste Pillard set out to make a hairspring resistant to excessive heat by using palladium. Instead, in 1877, he found that the balance spring made of palladium helped to combat magnetism. IWC utilized the patents made by Pillard to create two anti-magnetic movements with balances, balance springs, escape wheels and pallet levers all made from palladium while bronze was used in a park fork and gold in the arms. A low iron content in the design lead to a higher resistance to magnetism.

Anti-magnetic hairspring

Vacheron Constantin succeeded in making the first anti-magnetic pocket watch chronometer in 1915, just 60 years after beginning their experiments. They too used palladium for the escapement components. Following Vacheron Constantin, Tissot created the first serialized anti-magnetic wristwatch in 1930, called the Antimagnetique.

The Need for Anti-Magnetic Watches

In the 1940s, the British Royal Air Force requested a watch that could be resistant to the engines of the Spitfires and the Hurricane. To answer this request, IWC placed the movement of the Mark XI pilot’s watch inside a magnetic shielding case, also known as a Faraday Cage.

IWC Mark XI and RAF Spitfire

Rolex was commissioned to make a watch able to withstand the extreme levels the CERN scientists were exposed to, typically ten times the normal watch resistance. The Rolex 6541 Milgauss was the answer to this request and was produced in 1954. The French word for 1,000 Gauss is Mill Gauss, which is how they formed the name. The Milgauss represents the first watch to be resistant to such high levels of magnetism. To reach this accomplishment, the movement was placed inside a Faraday Cage with two interconnecting aluminum layers placed on top to increase the strength.

IWC Ingineur 666

Along with the Rolex Milgauss, IWC created the Inginieur Ref. 666 to be worn by engineers, technicians and other employees who worked in highly magnetic environments. Omega produced the Railmaster CK2914 in 1957 but it was only resistant to 900 Gauss rather than the 1,000 found in the Milgauss. You’ll see that many anti-magnetic watches feature the thunderbolt symbol to represent anti-magnetic abilities.

What is a Faraday Cage?

Named after British scientist Michael Faraday, who invented it in 1836, the Faraday Cage protects the movement. Rather than completely cancelling the magnetic field, it provides a pathway, guiding the field away from the movement inside. You’ll notice that many anti-magnetic watches using a Faraday cage do not have a date window or other open aperture on the dial or case back. This is because to work properly, the cage needs to be one continuous flow and as complete as possible.

Modern Advances in Watchmaking

As technology has advanced, and we’re seeing more items using a magnetic field, watchmakers have continued to experiment with their materials to protect the movement. In 1989, after surviving the Quartz movement, brands could put effort into the progress of anti-magnetic movements. This year brought about the IWC Ref. 3508, able to withstand 6,250 Gauss which was the highest to date.

Omega Anti-magnetic

The 2000s have brands experimenting with silicon balance springs.  In 2013, Omega released the Seamaster Aqua Terra >15,000 Gauss powered by the Caliber 8508. The 8508 is believed to be the first fully anti-magnetic mechanical watch movement. There is a silicon balance spring with staffs and pinons in the escapement made from NivaGauss. Having no Faraday cage protecting the movement, this anti-magnetic Aqua Terra can feature a date window and sapphire crystal case back.

What is the Omaga NivaGauss?

Much of the technology and science behind the NivaGauss is kept secret. We do know that it contains many non-ferrous materials to create a singular material used to create the staffs and pivots. Omega plans to roll out the material and movement in every model over the next few years to provide anti-magnetic technology for all consumers.


The ISO Standard

The International Organization for Standardization (ISO), originally published their watchmaking standard in 1973 with the ISO 764. This standard has since been revised, in 1814, 2002 and updated in 2013. It specifies the “minimum requirements and test methods for magnetic resistant watches.” A watch needs to withstand a direct current magnetic field of 4800 A/m and needs to keep an accuracy of +/- 30 seconds per day.

This standard set by the ISO sets the requirements for an anti-magnetic watch. A magnetic field can be measured in A/m (amperes per meter), G (Gauss) or by T (Tesla). Most commonly you’ll find that Gauss is uses to measure smaller magnetic fields, such as those for watches, as 0.1 Tesla equals 1,000 Gauss. The Earth measures .25 Gauss, a fridge magnet is 50 Gauss and an MRI can measure between 600 and 70,000 Gauss. Many anti-magnetic watches provide security from 1,000 – 15,000 Gauss.


Frequently Asked Questions About Anti-Magnetic Watches

In many cases, the reason for bringing in your watch service is from magnetism. Our watchmakers weigh in on some of your questions about magnetism and anti-magnetic watches:

    1. Why do I need an anti-magnetic watch?
      — You don’t necessarily need an anti-magnetic watch, although they are a great addition to your collection if you know you are going to be in an environment with stronger magnetic fields. Typically, the magnetic field you encounter daily won’t be strong enough to damage your watch. We recently had someone come with their watch that didn’t seem to be holding time. After further investigation, we found the watch was indeed magnetized and that the customer worked in a hospital which is full of magnetic fields.
    2. What happens when my watch is magnetized & what do i do?
      — Your watch may start to run erratically, either slowing down slightly or speeding up. In some instances the watch may stop completely. No matter how you watch is magnetized, it is important to take it in to a repair center for proper service to demagnetize the components.
    3. Is there anything I can do to know if my watch is magnetized, without taking it in for repair?
      — If you begin to notice that your watch may advance an hour on one afternoon, chances are it will be magnetized.  You can also tell if your watch is magnetized by putting a pocket compass flat over the balance cock. If magnetic, the compass needle will vibrate or spin around the dial. If your watch is not magnetic, you won’t see the needle move. Either way, we suggest always taking it in for repair if you ever think something may be wrong with your timepiece.
    4. Will excessive cell phone use cause my watch movement to be magnetized? If I sleep with my watch next to my iPad, alarm clock and phone, will it cause permanent damage?
      — Excessive cell phone use won’t cause your watch to become magnetized but a cell phone itself can. If you take off your watch and leave it on, or next to, your cell phone at night or for an extended period of time, it can begin to affect the time. This also happens with an iPad or alarm clock. Some speakers that are not shielded inside can also cause your watch to become magnetized. If you’ve ever moved  a speaker close to your television and seen interference, it will also damage your watch.
    5. Assuming that there are not other issues happening, if my watch gets magnetized, then corrected and then magnetized and corrected again…is there a possibility of permanent damage?
      — There is not typically permanent damage with magnetizing a movement, only that you need to demagnetize it again. We do suggest keeping an eye on what may be magnetizing the watch so you can look at how to avoid it happening again. In extreme cases replacing the balance, hairspring, mainspring and other affected parts of the movement may be necessary, which can  be determined when a watchmaker examines your timepiece.
    6. When traveling, will the security checks affect my watch?
      — Normally, the security points in an airport or metal detector arches won’t damage your watch. We do recommend avoiding placing your watch next to your iPad or Laptop, or even wrapping it in something and putting it in your bag. Don’t use the little bowl for change to put your watch through, there are some magnets in the motors that pull the belt that may affect the watch. The further away from the magnets, be better! Keeping your watch in your bag will also help avoid leaving your watch behind for someone to steal!
    7. What level of magnetism is likely to affect my watch?
      — Different strengths of magnetism can affect the watch in various ways. A lower field can cause the watch to run faster but will typically return to normal after the exposure subsides. A medium intensity causes a watch to run fast until it is serviced while a high intensity can stop a watch. Such things as putting your watch on a magnetic clasp or cell phone for extended periods can cause damages.

Want to ask the watchmakers something? Leave a comment below!



About Emily Smith
Emily loves the history of watches and loves learning how they work. Her watches of choice right now are her vintage Omega Ladymatic that is a mere 19mm and her 1973 Rolex Oyster with a navy dial. While she enjoys the look of vintage watches, she is excited to learn about new models and to build her collection.

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