Introduction: Best Ways to Find Magnets for DIY Projects at Home
Ever since I was young, I remember taking apart electronic devices to scavenge the magnets hiding inside them to use for DIY projects. In fact, one of my first Instructables (which I will not link to :) was a poor attempt at demonstrating just that.
Different devices contain different types of magnets - from the strongest neodymium magnets, to weaker ceramic magnets - all of which come in all shapes and sizes. In this Instructable I will go over:
- The best ways to source magnets
- The fastest methods for taking them apart
- Where not to look for magnets
- Lastly, some of my inventions and common uses for these magnets.
If you know of other sources where you can find magnets that I didn't mention, please leave them in the comments below!
Don’t want to read the Instructable? Watch the video instead!
Supplies
Most sources for magnets require simple hand tools you probably already have on hand to scavenge, however different sources require more specific tools to access which aren't as common. The links below are affiliate links.
- Torx screwdriver set / eBay (I have a few sets on hand since I always strips out the smallest T2-T6 torx bits on laptop HDDs)
- Bench vise / eBay
- Small philips/flat screwdriver (this Husky is my favorite) / eBay
- Philips screwdriver set / eBay
- Large strong flat screwdriver for prying or cold chisel / eBay
- Groove joint pliers / eBay
- Wire cutters or snips / eBay
Step 1: Speakers
Speakers are by far the best place for finding magnets. They contain ceramic magnets with a condenser, with smaller magnets (1/2" or 1cm and under) typically being neodymium magnets that are 5-10x stronger for the same size.
Ceramic speaker magnets are large dark gray donut-shaped magnets with a metal condenser piece in the center. You may be attempted to separate it from the condenser, but don't do that, as the name implies.
These are the most common type and are what can be salvaged from most speakers - desktop speakers, portable speakers, studio speakers and others - with the largest ones being inside subwoofers. A single magnet from a large subwoofer may weigh a few pounds (1-2 kg or even more).
Over the years, I've found the fastest and easiest method for separating the magnet from the basket (the cone-shaped part) is simply by crushing it in a bench vise (Aliexpress) as I show in the pictures. The basket crumples under the pressure and you're left with the magnet on top. If you don't own a vise, you can hammer a cold chisel (Aliexpress) or a flat screwdriver between the magnet and the basket or separate them simply by sticking the screwdriver in between and twisting to pry them apart. I use this method on subwoofer speakers that are too big to fit in my bench vise as well. This method works on almost all speakers but is harder on those that have been riveted together tightly.
Headphones - like their larger counterparts are a great source for magnets as well - and practically speaking are easy to find since they break and get replaced often so it's likely you have a few lying around.
Earbuds are a hit or miss method. Some have small strong magnets, but some are useless because of their shape or because they can't be removed without breaking.
Step 2: More Devices That Contain Speakers
Speakers aren't the only electronic device that contains...well, speakers.
Old TVs and external screens often have full-sized speakers. Most phones also have one or two speakers that contain small magnets as well.
Don't forget about those loud and annoying kids toys. Those have small speakers whose magnets are especially strong.
Step 3: Hard Drives
The strongest neodymium magnets I've ever found were from hard drives from desktop computers.
To open these you need a torx bit set with many different sizes (Aliexpress). Manufacturers don't want you to service them so they always hide one screw under the sticker. The magnet over the actuator is easy to unscrew, but the one underneath is a bit trickier to remove, sometimes requiring the actuator or platters to be removed first to get access to it. On some HDDs, there isn't even a magnet under the actuator.
These magnets are shockingly powerful. it's hard to pry them away from the hard drive, let alone separate them if they stick together. It's easy to get injured by these are well. They attract each other even from a distance, accelerate into each other and shatter into pieces producing sparks, or if your fingers are in the way they pinch your skin which can be painful.
The magnets in laptop HDDs are thinner and weaker but still very strong and useful for projects. You need to be extra careful opening their tiny torx screws since they strip out easily.
Step 4: Folding Devices That Utilize Magnets to Stay Closed
Many hinged electronic devices these days utilize small neodymium magnets to remain closed and to prevent them from opening accidentally.
This includes laptops which usually have 4-8 magnets, wireless earbuds and their cases, and phone and tablet cases. Don't forget to hack them apart before throwing them away!
Step 5: Optical Disc Drives
Old desktop computers often have one or two optical disc drives that are easy to pull out to harvest their magnets. Nowadays these are also a common item found in e-waste bins. Smaller versions of these can also be found in older laptops as well.
These are easy to disassemble, requiring you to unscrew the enclosure, pulling off the front and removing the plastic frame onto which all of the components are mounted to. You'll see the laser lens on 2 steel rods. Pulling off the lens housing will uncover several small yet very strong neodymium magnets. I've found a large variation between the size of the magnets in these, so don't be discouraged if you happen to take apart one that doesn't have the magnets you're looking for.
You'll also find a motor that's used to spin the disc. Most motors have strong disc-shaped neodymium magnet you can salvage as well.
Step 6: Magnetic Resistance Exercise Bike
Luck may determine your access to this source :)
I happened to come across a broken exercise bike out on the curb. I knew it would contain useful parts for future projects, but I didn't expect the flywheel to contain more ceramic magnets than I've ever seen in a single device.
These ceramic magnets were glued down tightly and I knew most would break if I tried pulling them off due to their brittle nature, so I tried bending what they were glued to hoping the adhesive would fail first, which worked quite well resulting in only a few chipped magnets.
Step 7: Microwaves... or NOT?
Microwaves are known as a common source for harvesting magnets. I wouldn't bother with them, however, and this is for several reasons.
First, microwaves have a 2kV capacitor. If this capacitor doesn't discharge properly by itself and you complete the circuit, it's game over.
Second, taking apart the magnetron in which two ceramic donut-shaped magnets are located can be extremely dangerous due to the ceramic-looking beryllium oxide insulators I show in the picture. Scratching or breaking these can cause permanent damage to your lungs and simply isn't worth the risk. Additionally, these magnets aren't useful for most projects. They are identical to speaker magnets whose condenser has been removed, so it's best to go through that route if that's what you're looking for.
It's simply not worth the risk.
Step 8: What Projects Have I Used Them For?
Over the past few years I've managed to amass a collection of over 40 pounds of magnets. Collecting, of course, isn't the goal. I've used these magnets for many projects including:
- Bike rack with a magnetic mount for a bike lock (HDD magnets)
- Magnetic Japanese saw guide for cutting boards accurately by hand (magnets from a magnetic cup sleeve)
- Tool wall mounts (magnets of all kinds but mostly from small speakers)
- Gluing a magnet to my impact driver to hold bits and screws (from an optical disc drive)
- Gluing a magnet for flashlights so I can stick them onto things
- Homemade magnetic honing guide for sharpening chisels
- Magnetic vise soft jaws
- Gluing magnet to a soap bottle, useful where there aren't shelves in showers such as the military or for traveling
If you have any clever uses for magnets, leave them below as I have a massive collection of magnets and struggle at finding enough things to do with them!
If you found this instructable helpful, I have over 100 more Instructables you may like as well. Check out my youtube channel as well for more videos of tips and tricks to save you time and money.