FAQ & History of Magnets
Magnets FAQ
A collection of our most asked questions. If your answer is not here get in touch with the team!
There are several simple methods that can be used to identify the (Scientific) North and South poles of neodymium magnets.
- The easiest way is to use another magnet that is already marked. The North Pole of the marked magnet will be attracted to the South Pole of the unmarked magnet.
- If you take an even number of magnets and pinch a string in the middle of the stack and dangle the magnets so they can freely rotate on the string, the North Pole of the magnets will eventually settle pointing north. This actually contradicts the “opposites attract” rule of magnetism, but the naming convention of the poles is a carryover from the old days when the poles were called the “North-seeking” and “South-seeking” poles. These were shortened over time to the “North” and the “South” poles that we know them as.
- If you have a compass handy, the end of the needle that normally points north will be attracted to the South Pole of the neodymium magnet.
- Use one of our Pole Identifier Devices.
No, both poles are equal in strength.
Ferromagnetic materials are strongly attracted by a magnetic force. The elements iron (Fe) nickel (Ni) and cobalt (Co) are the most commonly available elements. Steel is ferromagnetic because it is an alloy of iron and other metals.
Magnetic fields cannot be blocked, only redirected. The only materials that will redirect magnetic fields are materials that are ferromagnetic (attracted to magnets) such as iron, steel (which contains iron), cobalt, and nickel.
No we don’t, nor does anyone else, because they don’t exist. All magnets must have at least two poles.
Yes, two or more magnets stacked together will behave exactly like a single magnet of the combined size for example, if you stacked two of our ND155 disc magnets to form a 15 x 10mm combined size magnet, the two magnets would have the same strength and behave identically to our ND1510 discs, which are 15mm diameter x 10mm thick.
Gaussmeters are used to measure the magnetic field density at the surface of the magnet. This is referred to as the surface field and is measured in Gauss (or Tesla). Pull forces are used to test the Holding force of a magnetic that is in contact with a flat steel plate. Pull forces are measured in pounds (or kilograms).
Because pull force values are tested under laboratory conditions, you probably won’t achieve the same holding force under real-world conditions. The effective pull force is reduced by a number of factors such as;
Uneven contact with the metal surface, pulling in a direction that is not perpendicular to the steel, attaching to metal that is thinner than ideal, surface coatings, ambient temperature and humidity, iron content in the item you are attaching to and a number of other factors.
For this reason if you require a minimum level of pull force we always suggest going above what is needed rather than getting just enough.
Neodymium magnets are actually composed of neodymium, iron and boron (they are also referred to as NIB or Knife magnets). The powdered mixture is pressed under great pressure into moulds. The material is then sintered (heated under a vacuum), cooled, and then ground or sliced into the desired shape. Coatings are then applied if required. Finally, the blank magnets are magnetized by exposing them to a very powerful magnetic field.
Yes, we can supply custom magnets. Being a manufacturer of magnets we are able to manufacturer to any specification. Advise us of the size and quantity you require and we will give you a quote.
