1000 Gauss Magnet

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Putsimply, gauss is the unit of measure for the strength of a magnet.

However, gauss strength can be misleading, as the strength of the magnetic field decreases as the distance from the surface of the magnet increases.

Here is an example of why gauss rating can be so confusing, your cheap refrigerator magnet has a gauss of 100, the typical strength of the Earth's magnetic field at its surface is around only a half a gauss. So you can see that the strength of a magnet has many different factors.

This is why we ensure our magnets have an external manufacturers gauss rating of 1,000+. To penetrate one inch or 2.54cm into the tissue a magnet should have a 700 - 1000 gauss external strength.

The therapeutic magnets being used should have a steep enough magnetic field gradient so the field can reach the damaged tissue that is being targeted.

It has been a common practice for companies to claim 20,000+ gauss rating for a product with 20 magnets of 1,000 gauss in their product. This is misleading because the magnetic field still has a gauss rating of 1,000 at any given point on the support, it is not a cumulative effect.

This is incredibly important to us as we don't want to mislead any of our customers, the reality is, there is no reason to try and make your magnets sound stronger than they are when selling magnetic products if you are using high strength magnets.

The authors of this blog are not medical professionals, we, like most of our readers, are average people trying to share and support others in making healthier choices. We do our research to ensure all information is correct and recent however, we are human, so please do not take our opinions and information as medical or nutritional advice. Always seek your doctor's advice before making changes to your lifestyle.

Watchmakers care about magnetism because magnetism can, at worst, make a watch useless. There are a couple of different ways this can happen. Modern Nivarox-type alloys are reasonably resistant to weak magnetic fields, but if a watch comes into direct contact with a powerful permanent magnet, especially so-called rare earth magnets (the most powerful type, which thanks to their great strength, are popular as clasps and fasteners) the balance spring can become magnetized. The coils will begin to stick to each other, which increases the tension in the spring. A magnetized watch acts as if someone's put too strong a balance spring in it, and begins to run fast, because the balance can no longer swing through a full arc. The first time this happened to me was when I put my Speedmaster down by mistake on a cell phone case with a rare earth magnetic clasp. I knew what I'd done instantly and pulled the watch off, but it immediately started to run about 10 minutes fast per hour. A trip to the Omega boutique and a quick pass through a demagnetizer fixed things, but the incident impressed on me that while the strong magnetic fields we can run into in modern life are relatively rare, they're also potentially a very real problem.

Magnetism in everyday life comes from two sources: electromagnets and permanent magnets. Electromagnets are magnets in which the magnetic field is produced by moving current; permanent magnets are those which have a magnetic field on their own, without any electric current passing through them. Both can be hazardous to watches. It was thought at one time that only certain materials were affected by magnets, but we now know that all materials are affected to some degree. However, only so-called ferromagnetic materials produce fields strong enough for us to feel in everyday life. Ferromagnetic materials are those that can be magnetized; other magnetic interactions are generally too weak to be felt and require laboratory equipment to detect.

Understanding the source of magnetism is easier when you remember that a magnetic field is generated by a changing electrical field. The opposite is also true; a changing magnetic field inside a loop of wire will create a current. This relationship was discovered by Michael Faraday, in 1831 and is the principle behind electrical generators and motors.

Now the reason I'm (painfully) sticking a wrench to my hand with a 4K gauss magnet is because it's easier to understand how powerful the magnet is from a picture, than from expressing field strength in things like gauss or tesla, which are more abstract. There are actually two kinds of magnetic fields: B, and H. The so-called B field is a measure of field strength in free space, and is measured in tesla, or gauss. One tesla = 10,000 gauss; a typical refrigerator magnet is about 50 gauss, and our test magnet, at about 4,500 gauss, is nearly half a tesla, which is more than enough to fry any conventional watch. Obviously, the plain steel balance springs used in watches before the advent of Nivarox type alloys would be incredibly vulnerable to external magnetic fields, but even a watch with a standard modern Nivarox balance spring would be instantly rendered unusable by a magnet as powerful as the one we used in our test. Even with the high antimagnetic ratings of both the Milgauss and the Omega >15,000 Gauss, the idea of applying such a powerful magnet was a little alarming. It's one thing to know your car has an air bag; it's another thing to deliberately run it into a brick wall to find out if it works like it's supposed to.

As we mentioned before, the most common effect of magnetization is for a watch to run fast. There is, however, a subtler effect. If a spring containing ferromagnetic materials (like Nivarox) is exposed to ambient magnetic fields, the gradual accumulation of magnetism in the alloy can also interfere with the temperature compensation properties of the balance spring, and it may begin to run at different rates at different temperatures. The issue was described in a 2004 story for the Horological Journal by watchmaker Gideon Levingston, who was working at the time on his "Carbontime" oscillator system, which incorporated a carbon fiber balance spring intended to address this very issue. If you've been following Kari Voutilainen's work for a while you might even remember that Kari used the Carbontime oscillator in one of his watches, as PuristsPro reported via watchmaker and horological writer Curtis Thomson, in 2006.

Obviously magnetic fields can be a major problem for watches, watch owners, and watchmakers in both immediately obvious, and more subtle ways. Now let's look at two watches built to resist this hazard.

For the purposes of the test, the magnet was left on its styrofoam lower box and to prevent damage to both the magnet and the watch, a folded cloth was placed in between the two. Several earlier experiments with the magnet and ferromagnetic materials (by "experiments" I mean "randomly choosing heavy iron or steel objects to pick up") had produced scratched objects, a slightly chipped magnet, and a sense of the need for an abundance of caution when handling the HODINKEE Demon Core. The results were interesting to say the least.

Second up was the Milgauss. Now, this is the one that actually did make me nervous. Milgauss doesn't mean "resistant to a 4,000 gauss permanent neodymium magnet." It means just what it says: 1,000 gauss. Much to my surprise, and considerable relief, the visible effect on the watch was zero, and in fact, just as with the Omega, there was relatively little attractive force between the case and the bracelet. We allowed the Milgauss to run for 24 hours as well, and just as with the Omega, rate deviation, if there was any, wasn't visible.

Several interesting things came out of this little test. First of all, both of these watches apparently successfully shrugged off exposure to a magnetic field far in excess of anything you are likely to encounter in real life, at least unless you are the sort of person who likes to order extremely powerful rare earth magnets and stick watches to them.

The third interesting point is that there was no discernible difference at all between results from the Milgauss and from the Omega. This seems surprising at first, but remember, the first 1956 Milgauss had a conventional steel lever and balance spring in its movement (caliber 1080) and achieved its high level of resistance through the use of a soft iron casing. The latest version of the Milgauss has a non-ferromagnetic Parachrom balance spring and also uses non-ferromagnetic material for the escape wheel and lever, and it stands to reason that its resistance to magnetism should exceed 1000 gauss handily with these enhancements. As a matter of fact, the use of a niobium-zirconium alloy and non-ferromagnetic escapement components was the strategy used by IWC in its Ingenieur 500,000 A/m, which is equal to nearly 7,000 gauss as we've seen.

Rolex doesn't specify the material used for the inner shielding on the Milgauss, but it's reasonable to assume it's a type of nickel-iron mu-metal. Mu metals alloys work by providing a preferred pathway for magnetic field lines, which flow around the movement through the enclosure, rather than through the steel parts of the movement itself. (The term "mu-metal" is derived from the Greek letter mu, which is the symbol for magnetic permeability; mu-metals are highly permeable to magnetic fields.) By the way, you may have heard the term, "soft iron inner case." While pure iron is indeed relatively soft compared to steels, the term here means "soft magnetically." A hard magnetic material will stay magnetized even after an external field is removed; a soft magnetic material will conduct magnetic field lines but will not stay magnetized (which obviously is desirable when you're building a shield around a watch).

Everyone is going to have their favorite among these two watches but choosing one over the other requires balancing a number of technical questions against preferences in heritage, and style, that are highly personal. Personally I find the lightning bolt seconds hand of the Milgauss rather irresistible, but that's me (it reminds me of Reddy Kilowatt, the anthropomorphic electrical current character used as a utilities spokesman when I was a kid, and if that doesn't date me I don't know what does). At the very least, I came away from this experiment pretty convinced that both watches will make magnetic field pollution irrelevant to their respective owners, and that the deciding factor may well be less to do with resistance to magnetism, and more to do with whether or not you want a date window.

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