How To Re-Magnetize a Magnet - Complete How-To Guide

Magnets are some of the most simple objects, yet we seem to use them every day in one way or another. With that being said, it can be really frustrating when your magnet stops working or loses its strength in the middle of a task or project that you are trying to complete. In these instances, it helps to be aware of how to re-magnetize.

How can you re-magnetize a magnet? In order to re-magnetize the average magnet, you can use a stronger magnet such as neodymium. This will allow the weakened magnet to build off of the stronger force and regain its original form.

If you are trying to re-magnetize an electromagnet, on the other hand, you will need to go a completely different approach. This will include manipulating the coiled wires inside of the magnet with excessive levels of force.

The best part about re-magnetizing a magnet is that you don’t need a professional. In fact, you can re-magnetize your objects yourself, using very specific processes that can be safe and effective, so long as you keep safety in mind.

Today, I want to walk you through the simple process of re-magnetizing a magnet with another magnet, explaining electromagnets and how to revive them; showing you how to demagnetize the two types of magnets, as well.

Re-Magnetizing a Magnet

When the topic of re-magnetizing a magnet is brought up, there are several factors that need to be considered, with the most important one being which type of magnet you are seeking to revive.

If you know anything about magnetism, then you are probably familiar with all of the different types of magnets that exist in the world.

The two main types of magnets that we will be discussing today are permanent magnets, which are the most basic magnets that you probably have on your refrigerator at home, as well as the artificial electromagnet.

With that being said, there are completely different processes that each of these magnets must go through in order to regain their strength.

We will go into this information in more detail throughout the rest of this article, but for now, take a look at the data table down below to get a general overview.

Type of Magnet:Permanent MagnetElectromagnet (Temporary Magnet)
Re-Magnetizing Process: Using the magnetic force of another magnet to gain strength Manipulating the copper wires inside of the magnet with an external power source
How They Work: Using natural magnetic force to manipulate electrons and attract/repel other objects Using an electric current that flows through copper coils to create a magnetic force and attract/repel objects
How They Become De-Magnetized: Improper Storage
Mishandling
Overheating
Improper Storage
Mishandling
Overheating
*Loss of Current

How to Re-Magnetize a Magnet With Another Magnet

Imagine you have a perfectly good magnet to use for a new project you’re starting. Maybe you came across a nifty subreddit on magnet fishing, and you plan on trying it out tomorrow and are double checking your equipment before you trek out to sea.

Excited, you rush to gather your supplies, clear your schedule, and most importantly, double check your magnet.When suddenly, disaster strikes: your magnet doesn’t hold anything, and it slacks like a useless paperweight at the end of your rope.Your magnet has been demagnetized!

Don’t feel bad though; it is actually incredibly easy to demagnetize a magnet accidentally: storing magnets with others of similar polarity, mishandling them, damaging them, and overheating them are just some of the ways we can destroy our magnets.

Regardless of how it happened, whether it was by accident through improper storage, or you did it a while ago intentionally and just forgot, your tool is now a hunk of metal that can’t fulfill its intended purpose. How are you supposed to be a deep-sea adventurer without your magnet fishing hook?

Don’t worry, there are proven methods to re-magnetize most magnets for personal use, and the process could be much easier than you realize.

Without knowing how to re-magnetize household magnets, you risk running up a hefty bill of replacing them.

It doesn’t matter if it was a toy magnet or a pricey, double-sided neodymium magnet, replacing one every time it loses its magnetism can be impractical for a lot of us. This is part of the reason why I want to run down some common methods of remagnetization.

If you need to re-magnetize your magnet as soon as possible and do not know where to start, do not panic; you’re going to realize that it’s a no-brainer to restart and produce a magnetic field.

You do not need a lot of materials to get started. In fact, you really only need two pieces of equipment. This will consist of another magnet and a compass.

I know it may seem counterintuitive to get a new magnet to repair an old one. After all, why not just use the new magnet, right?

Depending on the use you have in mind for your old magnet, the magnet you use to restore it does not need to be the same type.

You’re going to need a neodymium magnet, which is a magnet composed of neodymium, iron and boron. Magnets like these are the strongest commercially available, and they’re a great way to restore the properties of your old magnet.

Here are some tips for using a Neodymium magnet before you get started:

  • Make sure you’re not using the strongest possible magnet available on the market -- using these kinds of powerful materials can pose a major safety hazard if you do not have experience handling them. This is especially true if you have any ferromagnetic materials in or on your body.
  • Use a magnet that is easily marked North and South. This will be important later.
  • Don’t use sphere magnets. They’re not clearly marked and can be very dangerous when used by amateurs.

Remember what I said about using the new magnet instead of the old? Well, if your purposes are anything but industrial-grade work, it is not necessary or safe to use neodymium for everything.

Magnet fishing is one exception, but it’s extremely important that you handle your magnet carefully: electronics can be destroyed when you bring them too close, credit cards can get wiped, and worse, people can get trapped, pulled, and severely injured by powerful magnets if they use them without the necessary safety precautions.

Anyways, let’s say you have your neodymium magnet ready to go; now all you need is your old magnet and the compass. You’re going to want to try and identify the poles of the neodymium magnet at this stage; if you do not, you will have no idea how to orient your old magnet and restore it to its former glory.

Place the compass next to your neodymium magnet, and note where the compass arrow points when you bring it close to either end of your magnet.

This is how you figure out which side is north and south on your neodymium magnet - the needle will point south when brought close to the north side of your magnet, and vice versa; the needle will point north when brought close to the south side.

By taking advantage of these repulsive forces, we can figure out the polarity!

Note: this is another reason why it is unwise to use a sphere magnet - there’s no reliable way to differentiate the north and south areas, so using one can be as frustrating as it is dangerous.

Once you have determined the poles of the neodymium, all you have to do is figure out the poles of your old magnet. Use the compass the same exact way; even a weak magnet can be deciphered when you use this method.

Now, we will move on to the process of re-magnetizing your old, dingy magnets.

It’s very simple: all you need to do is hold the south pole of the old magnet to the north pole of the neodymium magnet.

Repeat this step with the north pole of the old magnet, and the south pole of the neodymium. You may want to do this a few times, especially if your old magnet was significantly weakened.

And there you have it! You are once again the proud owner of a fully functioning magnet that can be used for the exact purpose you need it for.

Now, let us look at a more complex issue surrounding re-magnetizing a magnet. This time, it will be a certain type of magnet, one that you probably use more often than any other without knowing it.

Keep reading to find out how you can re-magnetize an electromagnet using a similar process.

How to Re-Magnetize an Electromagnet

An electromagnet is a magnet composed of a wire coil that produces a magnetic field whenever an electrical current is passed through it.

Often times the electromagnet is wrapped around a ferromagnetic material like steel in order to strengthen the force. They are extremely common in automobiles, MRI machines, and loudspeaker systems for their ease of activation and deactivation.

While a permanent magnet is always producing a magnetic field once it is magnetized, an electromagnet can only create a field when a current is run through its coils. Thus, its power is contingent on the strength of the current running through it.

One of the interesting aspects of an electromagnet that separates it from a typical permanent magnet is that its strength can be adjusted.

Once a permanent magnet is created, its properties and strength are determined by the field used in making it, and this cannot be changed unless you demagnetize it and start all over.

This is not the case for electromagnets; adjusting the strength of the current can also change the strength of the field!

And now, we come to the big issue of re-magnetizing an electromagnet. Let me be clear by saying that improper storage cannot demagnetize these kinds of magnets. The only thing that can demagnetize an electromagnet is by completely removing the current that runs through it.

Therefore, the process of re-magnetizing these is pretty easy, and can be completed by following a few simple steps:

  • Introduce a strong enough current into the coil again -- this is common in automobile engines that need electricity to operate their electromagnets.
  • Make sure the coil does not have too much current in it, such that it causes a short circuit.
  • If your electromagnet was demagnetized due to a power outage, simply fix the outage! Electromagnets need a constant supply of power, and reintroducing that will revive it.

Electromagnets are relatively easy to re-magnetize, but you are far less likely to need one if your occupation isn’t MRI technician or construction worker. Electromagnets, due to their size, are impractical for most everyday uses.

You are much better off using a permanent magnet that is versatile in shape. Plus the amount of current needed to activate most magnets is expensive to produce without a legitimate industrial reason.

So we have walked through the processes of re-magnetizing, but we have only scratched the surface of the converse: demagnetizing.

We should definitely do a thorough overview on the various ways a magnet can be demagnetized, both intentionally and accidentally. By doing so, I want to leave you with the best tools to keep your magnets strong, durable, and long-lasting.

Can You Demagnetize a Magnet?

If there’s one thing this article should have taught you by now, it is that magnets can lose their magnetic field through various ways. We have glossed over these incidents pretty quickly, so I want to examine them with a closer look.

Re-magnetizing is a cinch, and you would be surprised to know that demagnetizing can get a little more complicated in certain situations.

In some cases, demagnetizing requires no effort at all, while in others, it requires tons of work!

As previously mentioned, magnets remain a slight mystery in the world of physics.

Magnetic fields are still being studied, and through understanding the processes of demagnetization, maybe we can answer some interesting questions about their unknown properties.

Permanent magnets and electromagnets can lose their field through four major events, both intentional and accidental:

  • Improper storage
  • Mishandling or damage
  • Overheating
  • Loss of current - this only applies to electromagnets.

Improper storage means exactly that: storing your magnets together in a way that reduces their strength in the long term.

If you store your magnets side by side, with their opposite polarities against one another (i.e. the north side of one magnet is always next to the south side of the other) then you preserve their field without needing to worry about decreasing their power.

But let’s imagine that you just tossed multiple magnets in your drawer and did not fix their orientation in this way.

It is very easy for weaker magnets to lose their field if they are constantly in contact with an opposing field of another magnet. When you just leave them lying about next to each other like this, their opposing forces are acting on one another, demagnetizing them over time. This is possible to do intentionally, as well.

If you need to retire an old magnet for whatever reason, but don’t want the accompanying safety hazard of leaving a fully-powered magnet lying about, it would be very easy to expose your magnet to another one of an opposing charge. Doing so will gradually, but surely, demagnetize it.

This scenario is also an easy fix if you follow the process I presented here, but what if the demagnetization was due to damage? You have a slightly different problem on your hands.

When magnets are dropped, damaged or mishandled to the point that their shape significantly changes, they tend to lose their field. This is a property of magnets that is universal, as their function depends on their shape and orientation of their North and South poles, mainly for reasons science still cannot answer yet.

Now, you could very well want to demagnetize a magnet like this, and it’s very easy to if you just hammer it, drill into it, or throw it around.

Anything that will damage the perfect alignment of their electron fields, even at the physical level, can put a magnet out of commission, oftentimes for good.

Hammering your magnet again back to the way it was may not remedy the problem, so it is extremely important to handle your magnet with care if you hope to make it last for years.

Overheating a magnet is surefire way to stop a magnet from emitting a field. It is very similar to the logic of physically damaging it with blunt force.

Heating changes the orientation of the material at an atomic level, and causes the resulting magnetic field to disperse and die.

This is one of the few methods that can permanently alter the composition of the magnet, and repairing it after heating is a difficult task.

To be clear, it is extremely difficult to overheat a high-quality magnet accidentally. You would need to heat most magnets up to over 1390 degrees Fahrenheit; and unless you have access to this kind of heat off the cuff, it’s very unlikely you could do this yourself.

Quenching a magnet is the process by which heat is purposely introduced to an industrial-strength magnet like an MRI machine in the event of emergency.

The heat is so strong that helium actually boils off the machine and releases to the air!

Restarting the magnet after quenching costs upward of hundreds of thousands of dollars; this speaks to the amount of damage temperatures can cause, and the amount of care needed when handling a powerful magnet.

Finally, the loss of an electrical current can demagnetize an electromagnet very quickly.

It is part of what makes them so useful in different technologies like cars and loudspeakers: no lasting safety hazard, and no worries about spontaneous demagnetization.

When all you need is a coil, a metal and an energy source, the choice of using an electromagnet seems obvious.

But what if the electricity suddenly went out? Well in that case, you do have a bit of an issue.

Without a current, electromagnets cannot function, and thus, will remain inactive until their coils are reactivated.

For example, this situation is a little different than jumping a car battery; car batteries carry the charge they were imbued with indefinitely, but electromagnets need a constant flow of energy to function.

In this way, while highly versatile, their tendency to be demagnetized by way of removing the current may make them an inefficient choice for most of your hobbies.

In conclusion, understanding how magnetism works, and especially how to bend these forces in your favor can help you out in a jam.

Developing a process for re-magnetizing and demagnetizing can work wonders for starting hobbies and occupations ranging from car repair, medical imaging, and magnet fishing.

With this knowledge, you will be able to apply these skills on your next adventure into the world of magnetism. It is still a rapidly-growing field of study, and it is up to us to be our own personal scientists when handling such mysterious and powerful materials.