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FAQ

Ordering and Shipping

For Consumers:

Many of our products are available for purchase right here on our website, and everything is available to order over the telephone at 866-867-0941. Alternatively, you can ask for our brand of Magnet Source magnets at your local hardware, home improvement, and craft and hobby stores across North America. Finally, you can find major industrial supply catalogs online or visit other e-commerce retailers.

For Business:

We sell primarily through distribution partners, but if you are looking to use magnets in a product that you make or in your business facility, please contact our magnet experts who can answer your questions and process an order for fulfillment over the phone. Our permanent magnets, flexible magnetic material, and industrial magnetic devices can be ordered by calling us at 866-867-0971.

Distributor pricing is available, please contact us for more information.

We typically ship our magnets via the ground transportation carrier of your choice. Some permanent magnets can ship by air, but it is very expensive. Because of their ability to interfere with the navigation and electronic equipment on planes, many of our large industrial magnets, magnetic assemblies, and magnetic sweepers cannot be shipped via air. Shipping magnets by air is highly regulated as magnets will be classified as “Dangerous Goods” if not properly packed to block their magnetism. Contact our magnet experts regarding any magnets that you may need to expedite.

We accept Visa and MasterCard. For corporate customers, we will bill on terms pending the approval of a credit application. Please contact us for additional information.

Our products have a 30-day warranty. If our magnet fails while being used for its intended purpose, we will repair or replace the product. We are not responsible for breakage due to improper use or handling. We guarantee that our permanent magnets, under normal use, will remain magnetized or we will re-magnetize them.

Yes, we frequently fulfill custom magnet orders. With over 40 years of experience in magnetic innovations, we have the expertise to help your ideas become a reality. Share your drawings and specs, and let us work with you to generate the perfect magnetic solution with the right magnetic material for your application. We encourage you to discuss your needs with our magnet experts. It is not uncommon that a magnet requested as “custom” may already exist or be available for tooling, but may not be listed in our catalog.

We also make “custom magnets” in another sense by printing logos on magnets for custom promotional needs. Lead time is between 5 and 14 business days from artwork approval, depending on the product. See our full line of promo magnets.

We always recommend consulting with our magnet experts early in your OEM process so we can help keep your project on on your timeline. Depending on the magnetic solution for your application, tooling requirements, availability of materials and changes to prototypes, custom orders typically take between 2 and 18 weeks, depending on the material and complexity.

Magnet Basics

A magnet is any material that retains its magnetic properties in the absence of an inducing field or current. A magnet has at least two poles. The magnetic field leaves the north pole and enters the south pole. Two unlike poles attract each other, while two like poles repel each other.

All magnets are made of certain materials that create a magnetic field. Every magnet has at least one north pole and one south pole. Magnetic field lines leaving the north pole and entering the south is an example of a magnetic dipole ("di" means two, or two poles). If you break a bar magnet into two pieces, each piece will again have a north pole and a south pole. If you break one of those pieces into two, each of the smaller pieces will still have a north pole and south pole. No matter how small the pieces of the magnet become, each piece will have a north pole and south pole. It is not currently possible to create a monopole (single pole) magnet.

Rare earth magnets are a classification of extremely high-strength, permanent magnets made from alloys that are mined and part of the lanthanide series of elements in the periodic table. Rare earth magnets are not named so much for their elemental scarcity (they are actually found on all continents), but rather the difficulty with which the compounds are processed. The elements bond closely to one another and the process to separate them is time-consuming and dirty. While neodymium and samarium cobalt are both technically categorized as rare earth magnets, the term most commonly refers to neodymium.

Neodymium magnets are the strongest permanent magnetic material available. They have a very high strength packed into a very small size. Neodymium magnets have good stability and high field strength, but a relatively low operating temperature, meaning that they do not work well in high-heat applications. Be sure to contact our magnet experts to select the best magnet for your application.

In simplified terms, permanent magnets are made by being cast, sintered, or extruded. In the casting process, molten alloys are poured into forms to create the desired magnet shape. Sintering is the compression of powdered alloys into molds until a molecular change occurs. In both cases, heating and cooling cycles are instrumental in the creation of the magnet. The resulting material is magnetized after cooling and finishing. The magnetization process aligns the magnetic atoms to create a permanent magnet. Extrusion is the process of mixing powdered magnetic material with a binder, such as rubber or plastic, and forcing the mixture through differently shaped openings, depending on the desired final product. Magnetic sheeting can be made by extrusion or from a process called calendaring. Strip is typically extruded. Like cast and sintered magnets, the final step for extruded material is magnetization.

A permanent magnet is one that retains its magnetic properties after it has been magnetized. With proper use, it will remain magnetized throughout its lifetime. An electromagnet relies on electricity. In order to make an electromagnet, electricity must pass through a coil wrapped around a ferromagnetic core to generate a magnetic field. Without electricity, an electromagnet has no magnetic pull. Master Magnetics exclusively manufactures and distributes permanent magnets and magnetic assemblies.

Permanent magnetic materials are called “permanent magnets” since, under normal use, they lose only 0.5% of their power every one hundred years.

Technical

Permanent magnets are graded by the maximum energy the magnet produces. Each grade of magnet material generates a Maximum Energy Product, or MGOe (Mega Gauss Oersteds). Typically, the higher the magnet grade, the higher the corresponding strength of the magnet. It is one way to measure the strength of a magnet. In electrical engineering and materials science, the coercivity (also called the magnetic coercivity, coercive field, or coercive force) is a measure of the ability of a ferromagnetic material to withstand an external magnetic field without becoming demagnetized.

For ferromagnetic material, the coercivity is the intensity of the applied magnetic field required to reduce the magnetization of that material to zero after the magnetization of the sample has been driven to saturation. Coercivity then measures the resistance of a ferromagnetic material to demagnetization. Coercivity is usually measured in oersteds or ampere/meter units and is denoted as “Hc”. It can be measured using a B-H analyzer or magnetometer.

Ferromagnetic materials with high coercivity are called “magnetically hard materials” and are used to make permanent magnets. Materials with low coercivity are said to be “magnetically soft”. The latter are used in transformer and inductor cores, recording heads, microwave devices, and magnetic shielding.

Maximum Operating Temperature - The maximum temperature of exposure that a magnet can withstand without significant long-range instability (loss of magnetism) or structural changes.

Curie Temperature - Temperature at which a material loses its magnetic properties permanently.

Coercive Force, Hc - The demagnetizing force, in oersteds, required to reduce the residual induction (Br) of a fully magnetized magnet to zero (e.g. alnico has a low coercive force and can lose its strength if not stored properly).

Gauss is a unit of measure of magnetic induction (B) or flux density in the CGS system. One tesla is equal to 10 4 gauss.

Gauss, named for Carl Friedrich Gauss, a German mathematician and physicist, is abbreviated as G or Gs and is the unit of measurement of a magnetic field B (magnetic flux density or magnetic induction). One gauss is defined as one maxwell unit per square centimeter.

In the CGS system, an oersted is a unit of measure of the auxiliary magnetic field, H. One oersted is equal to 1000/4∏ amperes per meter. Oersteds are most commonly used in the measurement of a magnet’s field strength.

Typically, magnetic strength can be measured in one of two ways: by the grade (for magnetic materials) or by pull strength (for magnetic assemblies). Magnet grades are most useful for permanent magnetic materials, however pull strength is also available for raw materials. Pull strength is more frequently used to measure magnetic assemblies.

Pull strength or Max Force of magnetic assemblies is a reliable method of measuring the maximum strength, or holding power, that a magnet has before it is separated from ferrous material. It is measured in pounds or kilograms. Magnetic assemblies are measured by the pounds of pull in a vertical test. The higher the pull strength, the stronger the magnet. We rate our magnetic assemblies by pounds of pull or Max Force in a vertical test. Each magnet’s entire magnetic surface is tested against a 0.5-inch-thick ground steel plate. Pull tests are widely used across the industry and it is common for magnetic assemblies to have a rating of pounds pull in order to provide users with an accurate idea of the product’s strength, relative to other magnets. This methodology is the standard breakaway test used in the magnet industry as established by the International Magnetics Association (IMA) formerly developed by the Magnet Materials Producers Association (MMPA).

Poles of a magnet are the areas of the magnet where the magnetic field is the strongest – one pole is referred to as the north pole and the other is the south pole. Opposite poles attract each other while like-poles repel each other. Some magnets are magnetized with multiple poles per face or surface, which is referred to as a multipole magnetization.

This depends on the application of the magnet. For magnet-to-steel applications, either side of the magnet may be used. However, for magnet-to-magnet applications, such as closures and latches, selecting the correct pole is necessary. Opposite poles attract and like poles repel.

Visually, there is no way to tell which pole is north and which is south without a pole indicator or markings on the magnet. Some magnets, such as our neodymium magnets with adhesive, are stamped with an “N” or “S” to indicate the pole for easy matching. It is common to use a hand-held magnetic pole indicator to identify the poles of unmarked magnets.

General Magnet Questions

Under normal conditions, permanent magnets remain magnetized and are expected to only lose 0.5% of strength every one hundred years.

Yes, a magnet has the potential of losing its strength under specific or unique conditions, or if the magnet is made of certain magnetic materials. Exposing a magnet to temperatures above the maximum operating temperature for extended periods of time will reduce its strength. A magnet can also lose strength if it is exposed to a stronger opposing magnetic field for an extended period of time. The electrons of the smaller magnet are realigned by the larger force. This is illustrated when a neodymium magnet touches a piece of flexible magnet. The area of flexible magnet (the weaker magnet) will be demagnetized where it comes into contact with a piece of neodymium (the stronger magnet).

Alnico magnets will lose their magnetism if not stored with a keeper or “kept” attracted to a second magnet. They can also lose strength if dropped on the ground or forced together in a repelling match-up.

Yes, as long as it was not taken beyond its curie temperature, which causes irreversible change to the magnet. Alnico can be recharged or re-magnetized to original strength. Raw material or permanent magnetic materials may be re-magnetized to achieve full saturation. Magnetized magnetic assemblies may or may not be magnetized to greater strength, depending on the assembly.

No. Once a magnet is magnetized to full saturation, the material cannot be made stronger. It is similar to filling a bucket with water; once it is full you can’t add any more. However, if you need a stronger magnet, please contact us so we can help you find the right product for your application.

There are a few outside influences that can damage or weaken your magnet. The most common is temperature. Exposing a magnet to temperatures above the maximum operating temperature for extended periods of time will reduce its strength. Flash exposure to high heat could lead to loss of magnetism. Breaking or chipping the magnet surface may also lead to reduced strength. If you have an alnico magnet please refer to proper storing and handling requirements specific to this material.

Some magnetic assemblies with a strong pull strength or Max Force have a removable magnetic shield on the exposed poles to prevent the magnet from attracting to nearby ferrous metal objects. This is handy when you want to keep the magnet in your toolbox, but don’t want all the other tools to get stuck to the magnet. Alnico magnets come with keepers to maintain the original magnetic circuit. Many alnico cow magnets come in pairs to keep the magnetic circuit because they can be magnetically weakened from impact with other objects.

A magnetic assembly is created when a raw material permanent magnet is built into a metal housing of sorts to create a magnetic device. For instance, we make a magnetic assembly that we call a round base magnet, which is made by taking a ceramic ring magnet and attaching it to a shallow metal cup with a mounting hole in the middle. The finished magnet can be used in a variety of lifting and retrieving applications that the ring magnet alone could never be.

No, do not weld or solder magnets – the welding temperatures will damage the magnetism of the product, there is a potential fire risk, and the fumes from the coating and plating could be dangerous.

Machining or drilling into a magnet is a difficult, sometimes dangerous task and one best handled by experts. Magnets are inherently brittle and hard, which pose their own set of problems for machining. Machining or drilling can also cause the magnet to incur damage from heat buildup, resulting in the toxicity of the ferrite materials and cooling fluids as well as surface oxidization. Neodymium in powder form is highly flammable, so drilling a neodymium magnet can result in combustion.

It is possible to machine or drill magnets prior to magnetization, making the process slightly easier. Involving our team of magnet experts early in the magnet selection process helps to avoid any unnecessary drilling, machining, or redesign prototyping. Special equipment is necessary to machine or drill magnets and, in some cases, a special diamond cut-off or drill with water cooling is required.

One of the main reasons that magnets are coated is corrosion resistance. Rare earth magnets in particular are prone to corrosion and are almost always plated to prevent damage to the magnet. Nickel or zinc coatings on rare earth magnets can marginally affect the strength of the magnet, but other coatings that help prevent scratching or damage to painted surfaces will reduce the strength of the magnet more significantly, depending on the thickness of the coating.

Storage and Safety

Special care is required when handling magnets, especially neodymium, the strongest magnet material in the world. Please read our full list of Safety Warnings to ensure you carefully understand some of the precautions necessary when handling magnets.

New cell phones (manufactured in the last five years) are not susceptible to magnetic damage in the same manner their predecessors were. In fact, many cell phone accessories, including mounts and cradles, feature neodymium magnets. It is still possible, however, to damage a cell phone by exposing it to an industrial-strength magnet for an extended period of time. Caution is advised when using these types of magnets near a cell phone.

Separating magnets successfully requires an airgap between the magnets, and sliding, rather than pulling them apart. Our neodymium magnets normally come with either a plastic or heavy-cardboard spacer between them. We recommend keeping the spacers for future storage or transportation. You may need to use the edge of a table or hard surface to position the magnets at the point where they are joined  so it is easier to slide them apart.

Yes. Depending on the strength of magnet, it can interfere with a pacemaker, ICD, or other medical device. We recommend keeping magnets (especially neodymium magnets) away from areas where devices are implanted. Magnetic name badge backings are usually neodymium, so individuals with pacemakers should never wear a magnetic name badge.

Magnets should be stored in a dry, clean environment to avoid corrosion. Very strong magnets should be labeled, as they pose a risk to users who may be unaware of the their intense strength. It advisable to store magnets in their "off" position or with shields, if applicable.

Magnets are naturally brittle and can chip easily. If they accidentally snap together, it is common for them chip or even shatter. Take care to prevent dropping them or allowing them slam together or against a metal surface. For very strong magnets, it is safest to hold one firmly in each hand and slowly move them toward each other, then slide them together to keep them from colliding.

Flexible Magnetics

A dry mixture of ferrite powder and rubber polymer resin is mixed, calendared, and ground. It is then formed either by extrusion (for magnetic strip) or rollers (for magnetic sheeting). Next, the material is magnetized, laminated with vinyl or adhesive, cut to size, rolled onto a core, and boxed for shipment.

Flexible magnetic sheeting is typically magnetized with a neo fixture (magnetizer) which the sheeting slides across during the calendaring process.

It is usually true that the thicker the flexible magnet, the stronger it is. The number of poles per square inch also influences the material’s strength. For instance, high energy flexible magnetic material is stronger than standard sheeting.

Yes! Magnetic sheeting and magnetic receptive material can be trimmed by hand with scissors or a hobby knife. Professional printers can easily cut sizable pieces of magnetic sheeting with routers or large flatbed cutters to quickly finish large print runs.

Alnico, rare earth, and ceramic magnets do not attract very well to flexible magnet material. Even flexible-magnet-to-flexible-magnet attraction can be difficult due to the multiple pole magnetization common to these magnets. Because the poles do not line up well, the intended result may not be achieved.

Flexible magnets will attract flexible magnetic receptive material that can be printed to create multiple layers of magnetic graphics.

It’s not only possible to print direct to magnet, but it frequently saves both time and money. Depending on the ink system of your printer, you can print direct to the magnet with solvent, eco-solvent, UV and latex ink systems on our PrintMagnetVinyl ™ , ThinFORCE™ magnetic sheeting and on FlexIRON™ magnetic receptive sheeting. Aqueous inks require a paper topcoat like or PrintMagnet™ has. This creates a faster, more efficient and profitable process than the traditional two-step process of printing on another substrate such as vinyl,then laminating it to the magnet. Beautiful results are routinely achieved with the proper setup and recommended printer profiles. Contact your printer manufacturer for guidance.

Unfortunately, recycling magnets through mainstream consumer-accessible recycling centers is not available. However, we understand that there are scientists currently working on ways to reclaim rare earth magnet material. We recommend re-purposing unwanted magnets for crafting and tool-holding purposes.