What Is a Cup Magnet and How Do They Work?

Cup magnet by Monroe Engineering

Magnets come in a variety of shapes. Some of them are square, whereas others are rectangular. There are also round magnets, such as cup magnets. Cup magnets still produce a magnetic field, but they feature a round shape — as well as a small size — that makes them ideal for certain applications. What are cup magnets exactly, and how do they work?

Overview of Cup Magnets

Cup magnets are round magnets that are designed for use inside of a channel or cup. As shown in the adjacent photo, they look like an ordinary piece of round-shaped metal. Cup magnets, of course, are capable of producing a magnetic field. You can place them inside of a channel or cup to hold the respective object in place.

They are known as “cup magnets” because they are often used inside of cups. To stabilize a metal cup — and thus prevent it from falling over — you can use a cup magnet. Placing a cup magnet inside of the metal cup will secure it in place. Cup magnets can still be used in other applications, but they’ve become synonymous with cups.

How Cup Magnets Work

Like other types of permanent magnets, cup magnets are made of a ferromagnetic material. Most of them are made of neodymium. Featuring the atomic number 60, neodymium is a rare-earth metal that produces an exceptionally strong magnetic field. Cup magnets will cling to the inside of a channel or cup, thereby securing the respective object so that it doesn’t fall over.

Channels and cups have a round interior, which isn’t suitable for traditional square- or rectangular-shaped magnets. You may be able to place a small magnet inside of a channel or cup, but it won’t rest flush with the bottom. Cup magnets offer a solution. They are designed in a round shape that accommodates the inside of most channels and cups.

Choosing Cup Magnets: What You Should Know

When choosing cup magnets, you should consider how they are installed. Some of them have a bolt attached in the center, whereas others have a through hole or countersink hole in the center. With the latter type, you’ll need to use a separate bolt to install them.

You should also choose cup magnets in the right size for your application. While all of them are round, cup magnets are available in different sizes. Whether you’re planning to use them in channels or cups, you should choose cup magnets in the right size for your application

See Monroe’s Magnets.