Cylindrical neodymium magnets with adhesive

The difference stems directly from the location of the magnetic poles relative to the plane covered with adhesive tape. When you purchase a cylindrical neodymium magnet with adhesive in the version with pole A, its adhesive layer is on the north pole (N) side, whereas in the version with pole B, the adhesive is applied to the south pole (S) side. This designation is crucial when you mount two self-adhesive cylindrical magnets facing each other—attaching them to the surfaces of Magnet A and Magnet B will cause them to attract each other strongly once the gap is closed, whereas using two identical poles will cause them to repel each other constantly.

Improper installation is the main cause of the tape peeling off under load; therefore, the substrate must be thoroughly degreased with isopropyl alcohol or extraction gasoline. A cylindrical neodymium magnet with adhesive should be applied only to a dry, smooth, and dust-free surface (e.g., cardboard, plastic, varnished wood, or metal), pressing it firmly with your thumb for about thirty seconds. It is very important to wait a full twenty-four hours before using the joint for the first time, which allows the 3M adhesive film to reach its full structural integrity and maximum adhesion.

Sintered neodymium generates an enormous magnetic pull, which—if the magnet is suddenly pulled straight upward—can exceed the adhesive strength of the adhesive film and cause the cylindrical neodymium magnet with adhesive to detach from the substrate. To avoid this problem, sealed components (e.g., in boxes, packages, or samples) should be designed so that they can be separated by lateral displacement (shear), where the magnetic resistance is significantly lower. An alternative solution is to use, on the other side, not a second magnet but a plain low-carbon steel plate, which reduces the risk of the component being torn off the adhesive tape.

The adhesive layer and the sintered neodymium have limited resistance to weather conditions and elevated temperatures. Moisture, direct UV radiation, and extreme cold gradually weaken the adhesive layer, causing the bonding layer of a cylindrical neodymium magnet with adhesive to crack. In addition, the nickel coating that protects the magnet from corrosion can be damaged by prolonged exposure to water, which is why self-adhesive products are primarily intended for indoor use or enclosed housings where the operating temperature does not exceed sixty degrees Celsius.

Thanks to the low profile of the flat, adhesive-backed cylindrical neodymium magnet, it can be easily glued into pre-milled or die-cut slots in cardboard and bookbinding applications. After removing the protective paper tape, the self-adhesive cylindrical neodymium magnet is placed in the recess so that its top surface is flush with the surface of the material; the entire assembly is then covered with a thin veneer, decorative paper, or laminate. This design ensures a completely invisible, aesthetically pleasing magnetic closure, while also protecting the adhesive tape itself from being physically pried open.