Pot magnets are among the most versatile magnetic products available, offering exceptional holding power in a compact design. They are used across manufacturing, engineering, retail displays, signage, automotive applications, and countless DIY projects.
When choosing a pot magnet, one of the first decisions you'll encounter is whether you need an internal thread or an external thread pot magnet.
Although both types provide the same strong magnetic holding force, the way they are mounted and used is quite different.
This guide explains the key differences and helps you choose the right option for your application.
What Is a Pot Magnet?
A pot magnet is a permanent magnet enclosed within a steel housing. The steel casing focuses the magnetic field onto one working face, significantly increasing the magnet's holding force while protecting it from damage.
Pot magnets are commonly manufactured using:
- Neodymium
- Ferrite
- Alnico
- Samarium Cobalt
Neodymium pot magnets are the most popular due to their exceptional strength and compact size.
What Is an Internal Thread Pot Magnet?
An internal thread pot magnet features a threaded hole in the centre of the rear face.
This threaded insert allows accessories or fixings to be screwed directly into the magnet.
Common accessories include:
- Bolts
- Eye bolts
- Hooks
- Brackets
- Custom fixtures
Because the fixing screws into the magnet itself, the front magnetic face remains completely flat for maximum contact with the steel surface.
Common Applications for Internal Thread Pot Magnets
Internal thread pot magnets are widely used for:
- Hanging signs
- Exhibition displays
- Machine guards
- Inspection equipment
- Lighting fixtures
- Workshop accessories
- Retail displays
- Temporary mounting systems
They are particularly useful when accessories may need to be removed or replaced regularly.
What Is an External Thread Pot Magnet?
An external thread pot magnet features a threaded stud permanently attached to the rear of the magnet.
Instead of attaching a bolt into the magnet, the stud itself passes through a bracket or mounting hole and is secured using a washer and nut.
This creates a strong and permanent fixing.
Common Applications for External Thread Pot Magnets
External thread pot magnets are commonly used in:
- Industrial machinery
- Fabrication equipment
- Production fixtures
- Jigs
- Machine building
- Automation systems
- Engineering assemblies
They are ideal where the magnet forms part of a fixed installation.
Key Differences
| Feature | Internal Thread | External Thread |
|---|---|---|
| Fixing Method | Threaded hole | Fixed threaded stud |
| Accessories | Bolts, hooks, eye bolts | Washer and nut |
| Installation | Flexible | Permanent |
| Replacement of Accessories | Easy | Not usually required |
| Best For | Displays, hooks, removable equipment | Machinery, engineering, production |
Which Type Is Stronger?
A common misconception is that one thread type produces greater magnetic strength than the other.
In reality, both designs produce virtually identical magnetic holding force, provided they use the same magnet size and material.
The difference lies entirely in the mounting method, not the magnetic performance.
Which Should You Choose?
Choose an Internal Thread Pot Magnet if you need:
- Flexibility
- Replaceable accessories
- Eye bolts or hooks
- Adjustable fixtures
- Temporary installations
Choose an External Thread Pot Magnet if you need:
- Permanent mounting
- Machinery installation
- Engineering fixtures
- Production equipment
- Strong mechanical fixing
Factors to Consider
Before selecting either type, consider:
Holding Force
Choose a magnet with sufficient pull force for your application.
Thread Size
Ensure the thread matches your intended accessories or mounting hardware.
Available Space
Internal thread designs can be more compact in certain installations, while external thread magnets may require additional clearance for the stud and securing nut.
Environment
If the magnet will be exposed to moisture or outdoor conditions, consider corrosion-resistant finishes or rubber-coated alternatives where appropriate.
Typical Industries Using Threaded Pot Magnets
Threaded pot magnets are widely used throughout:
- Manufacturing
- Engineering
- Automotive
- Warehousing
- Retail
- Signage
- Construction
- Exhibition design
- Maintenance
- Robotics and automation
Their combination of strong holding power and simple installation makes them one of the most adaptable magnetic solutions available.
Why Pot Magnets Are So Popular
Regardless of thread type, pot magnets offer numerous advantages:
- High holding force
- Compact design
- Quick installation
- Reusable fixing
- Durable steel housing
- Low maintenance
- Wide range of sizes and thread options
These benefits make them suitable for everything from lightweight display systems to demanding industrial applications.
Final Thoughts
Choosing between an internal thread and an external thread pot magnet isn't about which one is stronger—it's about selecting the mounting style that best suits your project.
If you require flexibility and interchangeable accessories, an internal thread pot magnet is usually the best choice.
If you're creating a fixed installation or integrating the magnet into machinery or equipment, an external thread pot magnet often provides the most secure solution.
By understanding the differences between the two designs, you can select the right pot magnet for your application and ensure reliable, long-lasting performance.