A Mechanical Movement's Worst Enemy: Magnetism

What plagued mechanical movements 80 years ago is still a problem today, and perhaps even more so. Magnetism, both in its natural form coming from Earth’s magnetic field and in an artificial form coming from the machines we surround ourselves with all the time. The more technology we use, the more harm we might cause to our beloved wrist-worn timekeeping devices. You might remember that the first Rolex Milgauss, released in 1956, was specifically designed for engineers and scientists who worked around electronic machines. They had to have a functional watch that could withstand exposure to high levels of magnetism so that they could keep track of their work day. Nowadays we may not think that our watches are subject to magnetism but I would beg to differ. So, let’s talk about magnetism and what we can do to protect these marvels of technology.

Source: www.thewatchbox.com

Being a Watch Collector in the 21st Century

Between the moment I woke up this morning and sat down at my desk to start working on this article, I exposed my mechanical watch to several sources of magnetism: my phone on which I checked my messages while sipping a cup of coffee; the microwave I used to heat up my breakfast; the car I drove to get to my office; and lastly, the laptop itself. I’m only a couple of hours into the day. So, imagine what happens for those who work in labs, at the airport, in an office surrounded by computers and smartphones, or even those who are much braver than I and go to the gym and expose their watches to the magnetic fields coming from the modern fitness equipment and TV screens.

Source: www.flexjobs.com

Most watches I wear and review as a journalist do not come with any sort of protection against magnetism. This means that, more often than I would like, my watches run fast. Whether they were exposed to X-rays in transit through the airport or sat for too many hours next to a computer at customs. I don’t mean to sound paranoid, but I do believe these things happen quite often. After all, whenever I google “my watch is running fast” someone in the comments section will ask “have you recently been to the airport?”. Yes, that’s a legitimate response to provide and each time I travel, I worry my watches will get magnetized. Perhaps I’m quite unlucky, but it does happen more than I would want to admit. 

Source: www.travelandleisure.com

Watches That Are Highly Paramagnetic 

So what can we do? First of all, we could choose watches that are protected against magnetism. If you have $13,000 lying around, you could get yourself a brand new IWC Ingenieur which can withstand magnetic fields of up to 80,000 A/m (ampere per meter) or 1,000 Gauss (same as the Rolex Milgauss, hence its name). Nowadays, most watches that are considered paramagnetic, in other words fully protected against magnetism, can withstand magnetic fields of up to 33,000 A/m which is considered excellent. In order to get such a watch, you need to look for models that are equipped with soft-iron cages (also called Faraday cages). Iron is an alloy that absorbs magnetic fields therefore protecting the movement inside from them. 

Source: www.iwc.com

Movements that Are Paramagnetic 

The other solution is to get a watch that is equipped with a paramagnetic hairspring. As I wrote in this article, a movement is officially considered to be protected against magnetism if it can withstand magnetic fields of at least 4,800 A/m. Keeping in mind that a laptop generates magnetic fields of about 16,000 A/m, you can see how easy it is to expose our mechanical watches to their worst enemy while going about our daily business. Rolex created the Parachrom hairspring which is made of niobium and zirconium with are paramagnetic elements, while many brands from the Swatch Group use silicon as a material to make their hairsprings in their popular Powermatic calibers. Either solution guarantees a high resistance against commonly-found magnetic fields.

Source: www.bobswatches.com

What You Can Do At Home 

If, like me, you own neither an IWC Ingenieur nor a Swatch-made mechanical timepiece, you can get yourself a demagnetizer. I bought mine from Amazon for $13 and it has been a life-saver. Honestly, I always thought I was extremely unlucky as I often have watches that run fast (as a reminder, magnetic fields affect the hairspring of the balance wheel which causes the watch to run fast). So, having a demagnetizer at home has saved me from numerous trips to my local watchmaker—and it has saved me a lot of money too. Demagnetizing a watch is easy to do at home and only takes a couple of minutes. If you would like to know how to use a demagnetizer, let me know in the comments!

Source: www.misterchrono.com

The other solution is to store your watches away from electronic devices at home. When you travel, please keep your watches away from your extra battery pack, laptop charger, or even computer mouse! I made the above mistake during my summer vacation and ended up with two out of three watches gaining 30 seconds per day! Being an absolute watch nerd, however, I ordered a demagnetizer and had it delivered to my hotel! 

Source: www.hodinkee.com

Final Thoughts 

There are many things that could happen to a mechanical movement which would affect how well—or how poorly—it runs. We can knock the watch against a door frame, drop it on the kitchen floor, or forget to screw down the crown before swimming: all of which would have a negative impact on the movement. But, I feel that a mechanical movement’s worst enemy remains magnetism. It is what affects my watches most: whether I’m home working on an article or traveling. Even though technology has made a lot of progress, most of us cannot afford an IWC Ingenieur, Rolex Milgauss, or are not interested in a Swatch-group timepiece from Tissot. I’m a fervent supporter of micro and independent brands and these brands rarely offer anti-magnetic watches or movements. 

I said rarely, not never.