How to Get Maximum Pulling Force from Your Magnets

A magnet's pulling force isn't fixed. The same magnet can perform very differently depending on how you use it. This guide walks you through material selection, installation, and maintenance to help you get the most out of your magnets.

Step 1: Choose the Right Magnets

Bigger isn't always better, and more expensive isn't always better either—the key is choosing the right magnets for your application.

Go for Higher-Grade Magnets

If size is fixed, going up in grade is the most direct way to boost pulling force. For example, an N52 neodymium magnet has about 1.5 times the energy product of an N35—so the difference in pulling force is significant.

One thing to keep in mind: higher-grade magnets are more brittle, so handle them carefully during machining and installation.

Pick the Right Shape for Your Magnets

In general, use as much magnet volume as your space allows.

• For vertical holding force, like hanging something, choose a thicker magnet. The magnetic field is stronger along the magnetization direction.
• For shear force, like sliding along a surface, go for a larger diameter or surface area.

Match Magnets to Operating Temperature

If your environment exceeds 80°C, you need temperature-rated magnets. For example, at 150°C, you should use SH series magnets instead of standard N series. High temperatures can cause permanent demagnetization.

Stanford Magnets offers neodymium magnets in N, M, H, and SH series, as well as AlNiCo and ferrite magnets.

Step 2: Optimize Mounting and Design for Your Magnets

You can pick the perfect magnets, but if you mount them wrong, you'll lose more than half your pulling force.

Eliminate Air Gaps—This Is Critical for Magnets

Magnetic force drops exponentially with distance. Even a 0.1 mm gap can reduce pulling force by over 20%.

DO

• Ensure the magnet surface makes full contact with the workpiece
• Use countersunk holes to recess the magnet into the mounting surface instead of placing it on top
• If your part has a coating, consider installing the magnet after the coating is applied

DON'T

• Don't cover the magnet surface with thick coatings or protective layers
• Don't let the magnet sit above the mounting base—this creates a step gap
• Don't ignore rust or paint thickness on the workpiece surface

Use Proper Magnetic Circuit Design for Your Magnets

An exposed magnet has scattered flux. Adding a steel yoke (mild steel cap or backing plate) channels the magnetic flux so it's concentrated at the working face—greatly improving effective pulling force. A single magnet by itself gives you a weak hold by comparison.

Step 3: Install Your Magnets Correctly

How you install your magnets determines the final holding force you actually get.

Proper Installation Method for Magnets

• Vertical hold: Position the magnet face flat and parallel to the workpiece surface—that's where you get maximum force
• Slide into position: Avoid slamming the magnet against the workpiece. Slide it into place to prevent cracking or chipping
• Use tools for large magnets: For large or high-grade magnets, always use non-magnetic tools like wooden wedges or plastic pry bars for positioning

Watch Out For

• These magnets can pinch your fingers—keep them clear of the gripping surfaces
• Don't use steam or open flames on magnet assemblies
• Keep magnets away from other strong magnetic fields that could alter their magnetization

Step 4: Regular Inspection and Maintenance of Your Magnets

Magnets can lose strength over time—but proper care slows that down.

Daily Checks for Your Magnets

• Look for iron filings or debris on the surface. These tiny particles create extra air gaps that weaken holding force.
• Check the coating for damage. Cracks not only invite corrosion—the rust layer also adds thickness and increases the air gap.
• Make sure the operating temperature stays within the rated limit.

Maintenance Tips for Your Magnets

• Wipe the magnet face regularly with a soft cloth to remove dust and filings
• Touch up minor coating damage with rust-preventive paint or sealant
• Use a gaussmeter periodically to measure surface field strength and compare it with baseline readings to catch any demagnetization early

Step 5: Common Myths About Magnets vs. Facts

Myth 1: Thicker magnets always pull harder
Not necessarily. Once the workpiece thickness exceeds the magnet's diameter, extra thickness gives diminishing returns. Good magnetic circuit design often matters more than just adding bulk.

Myth 2: Magnets of the same size have the same force
Grades, manufacturers, and even batches can vary by over 20%. Always ask for full magnetic performance test reports.

Myth 3: A thin sheet between surfaces doesn't affect magnets
Even a 1 mm plastic layer can cause over 30% force loss. In a magnetic circuit, all non-ferromagnetic materials count as air gaps.

Myth 4: Magnets lose strength over time on their own
If you stay within the rated temperature limits, good-quality neodymium magnets lose less than 1% per year—so they basically last forever. The real culprits are excessive heat and strong opposing magnetic fields.

Myth 5: Stacking two magnets doubles the force
When in full contact, two magnets don't double the force—you might see a small increase, but it's far less efficient than using a single, thicker magnet of the same total volume.

Summary

The best use of the magnet for its pull comes not only from selecting the strongest one but also from selecting the correct type of material, designing the mount correctly, and performing proper installation and maintenance. If everything is done correctly, then the performance of the magnets will be optimized.