How to Choose Flexible Magnetic Sheeting for Your Application

Choosing flexible magnetic sheeting is not simply a matter of selecting a thickness.

The best material depends on the complete application: the target surface, required holding performance, print or adhesive requirements, dimensions, load direction, environment, fabrication method and how the finished product will be handled.

A 15 mil, 20 mil or 30 mil magnetic sheet can each be the correct choice in the right situation. Likewise, standard magnetic material, higher-performance formulations, printable constructions and adhesive-backed products each serve different functions.

The most reliable selection process begins with one question:

What does the finished magnetic product need to do?

Table of Contents

• 1. Start With the Application
• 2. What Surface Will the Magnet Attach To?
• 3. How Much Holding Performance Do You Need?
• 4. Choose the Appropriate Thickness
• 5. Standard vs Higher-Performance Magnetic Material
• 6. Consider the Load Direction
• 7. Identify Any Air Gap
• 8. Do You Need to Print on the Material?
• 9. Do You Need an Adhesive Backing?
• 10. Consider Size, Weight and Handling
• 11. Indoor, Outdoor and Environmental Conditions
• 12. How Will the Material Be Cut or Converted?
• 13. Do You Actually Need Magnetic or Magnetic-Receptive Material?
• 14. Flexible Magnetic Sheeting Decision Guide
• 15. Specification Checklist
• 16. Common Selection Mistakes
• 17. Frequently Asked Questions

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1. Start With the Application

Do not begin with:

“I need 20 mil magnetic sheeting.”

Begin with:

“This is what I need the magnetic material to accomplish.”

That shift is important because flexible magnetic sheeting is available in different constructions designed for very different uses.

Before selecting a product, define:

• what the finished piece is;
• what surface it must attach to;
• how large it will be;
• how much holding performance is required;
• how the load is oriented;
• whether there is an air gap;
• whether printing is required;
• whether adhesive is required;
• whether the application is indoor or outdoor;
• how the material will be cut or converted;
• how often it will be installed, removed or changed.

2. What Surface Will the Magnet Attach To?

The target surface is one of the first things to verify.

Flexible magnetic sheeting generally requires a suitable ferromagnetic surface for magnetic attachment.

Common suitable targets can include certain steels, but performance depends on:

• steel composition;
• steel thickness;
• surface flatness;
• paint or coatings;
• corrosion;
• contamination;
• available contact area.

Not every metal is magnetic.

Aluminum, for example, does not behave like ordinary ferromagnetic steel and should not be assumed to provide magnetic attraction.

If the intended surface is not magnetic, the application may require:

• a steel or magnetic-receptive layer;
• a permanent magnetic base;
• adhesive-backed magnetic material;
• or a different attachment system entirely.

For the fundamentals of how flexible magnetic material works against steel, see SSKC-026 — Flexible Magnetic Sheeting Explained.

3. How Much Holding Performance Do You Need?

Not every application needs maximum magnetic holding force.

A lightweight warehouse label placed flat against clean steel has very different requirements from a large graphic installed vertically or on moving equipment.

Consider:

• finished product weight;
• surface area;
• load direction;
• risk of sliding;
• vibration;
• movement;
• air gap;
• environment;
• consequences of detachment.

Holding-force data can be useful, but only when the test conditions are understood.

A number measured against one steel target under direct-contact laboratory conditions does not automatically represent the finished application.

4. Choose the Appropriate Thickness

Once the application requirements are understood, thickness becomes easier to evaluate.

Common flexible magnetic sheeting thicknesses include:

• 15 mil;
• 20 mil;
• 30 mil.

In comparable constructions:

• 15 mil generally offers lower weight and greater flexibility;
• 20 mil provides a useful balance between flexibility and magnetic capability;
• 30 mil provides more magnetic material, greater body and potentially greater holding capability.

However, thicker is not always better.

Additional thickness can increase:

• weight;
• material cost;
• stiffness;
• shipping requirements;
• handling difficulty;
• printer or converting limitations.

For a detailed comparison, see SSKC-031 — 15 mil vs 20 mil vs 30 mil Flexible Magnetic Sheeting.

5. Standard vs Higher-Performance Magnetic Material

Thickness is not the only way to increase magnetic performance.

Flexible magnetic materials can also be produced using different formulations and magnetic particle systems.

A higher-performance material may provide greater magnetic capability than a standard material of similar thickness.

This means that the design question may sometimes be:

Should I use a thicker standard material, or a thinner higher-performance construction?

The answer depends on:

• required holding performance;
• finished weight;
• available thickness;
• flexibility;
• cost;
• target surface;
• air gap;
• fabrication requirements.

Do not assume that “high energy,” “high strength” or similar terminology has exactly the same meaning across all manufacturers. Compare actual performance data and test conditions.

6. Consider the Load Direction

A flexible magnet attached to a horizontal steel surface behaves differently from one installed vertically.

In a direct pull-off direction, magnetic attraction resists separation from the steel.

In a vertical application, gravity may instead try to make the piece slide downward.

Sliding resistance depends on more than magnetic attraction. It also depends on friction between the surfaces.

Important variables include:

• magnetic normal force;
• surface finish;
• friction coefficient;
• finished product weight;
• surface contamination;
• load distribution;
• vibration.

A material that appears strong in a direct pull test may not provide the same apparent performance in a vertical application.

7. Identify Any Air Gap

An air gap is any non-magnetic separation between the magnetic material and its target.

It may be created by:

• paint;
• vinyl;
• laminates;
• protective films;
• adhesives;
• surface texture;
• contamination;
• curvature;
• uneven contact.

Flexible magnetic materials are commonly designed for very short working distances. Their multipole magnetization can provide useful attraction near the surface, but performance can decrease as separation increases.

If your application includes several non-magnetic layers, do not select the material based only on direct-contact holding data.

For more information about the pole pattern used in flexible magnetic material, see SSKC-027 — Pole Pitch and Multipole Magnetization.

8. Do You Need to Print on the Material?

If the finished product will be printed, the magnetic construction must be compatible with the printing process.

Consider:

• printer technology;
• maximum media thickness;
• media transport system;
• roll or sheet format;
• printable surface;
• ink or toner compatibility;
• heat exposure;
• dimensional stability;
• finished graphic size;
• lamination requirements.

Not every magnetic sheet is designed for direct printing.

Some products may use a printable face or laminate, while others may be intended to have a printed graphic laminated onto the magnetic substrate.

Likewise, simply being physically thin enough to enter an imaging device does not guarantee compatibility.

Confirm the specific media and equipment combination before production.

9. Do You Need an Adhesive Backing?

Adhesive-backed magnetic sheeting is useful when the magnetic material needs to be permanently attached to a non-magnetic substrate while leaving the opposite face available for magnetic use.

Possible substrates include:

• plastic;
• foam;
• board;
• metal;
• display components;
• industrial parts.

However, the adhesive must be selected for the actual substrate and environment.

Important factors include:

• surface energy;
• surface texture;
• temperature during application;
• indoor or outdoor use;
• moisture;
• heat;
• cleanliness;
• expected service life.

10. Consider Size, Weight and Handling

The dimensions of the finished piece matter.

A small magnetic label and a large-format magnetic panel may use the same nominal material but behave very differently in practice.

As the size increases, consider:

• total finished weight;
• ease of installation;
• flatness;
• rolling and unrolling;
• storage;
• shipping;
• edge lifting;
• surface contours;
• number of installers required.

Large-area applications often benefit from thinking about the complete finished graphic rather than only the magnetic material specification.

11. Indoor, Outdoor and Environmental Conditions

Environmental exposure can affect more than the magnetic compound itself.

A finished magnetic product may contain:

• flexible magnetic material;
• a surface film;
• a printable layer;
• ink;
• laminate;
• pressure-sensitive adhesive.

Each component can have different limitations.

For outdoor use, consider:

• temperature range;
• freeze-thaw cycling;
• sunlight and ultraviolet exposure;
• moisture;
• rain;
• road salt;
• dirt and contamination;
• wind and movement;
• frequency of removal.

12. How Will the Material Be Cut or Converted?

The fabrication method should be considered before the material is selected.

Depending on the construction and thickness, flexible magnetic material may be processed using methods such as:

• knife cutting;
• slitting;
• guillotine cutting;
• die cutting;
• kiss cutting;
• laminating;
• other suitable converting methods.

Not every magnetic construction is compatible with every cutting process.

In particular, do not assume that flexible magnetic material is suitable for laser cutting simply because it can be mechanically cut.

Laser suitability depends on the complete material composition, including any polymer binder, facing, coating, adhesive or laminate.

Always confirm the complete construction and process safety before using a thermal or laser-cutting method.

13. Do You Actually Need Magnetic or Magnetic-Receptive Material?

Some applications do not require the replaceable graphic itself to be magnetic.

For example, a system can use:

• a permanent magnetic base;
• plus a thin magnetic-receptive graphic.

This can be useful when graphics are changed frequently.

By contrast, if the graphic must attach directly to an existing steel surface, printable magnetic sheeting may be the simpler solution.

Before selecting magnetic sheeting, ask:

Which layer in the system actually needs to create the magnetic field?

For a complete explanation, see SSKC-030 — Magnetic vs Magnetic-Receptive Materials.

14. Flexible Magnetic Sheeting Decision Guide

Question	If Yes	If No
Is the target surface suitable ferromagnetic steel?	Flexible magnetic material may attach directly	Consider a magnetic base, receptive layer, adhesive or alternate system
Does the graphic need to be printed directly?	Choose a compatible printable magnetic construction	Plain, adhesive-backed or laminated magnetic material may be possible
Will graphics change frequently?	Evaluate magnetic + magnetic-receptive systems	Direct magnetic graphics may be simpler
Is low finished weight important?	Start with thinner constructions and verify performance	Thicker or higher-performance material may be acceptable
Is there a meaningful air gap?	Evaluate higher-performance constructions and test the finished system	Direct-contact product data may be more representative
Is the application vertical, moving or exposed to vibration?	Evaluate sliding, friction and safety margin	Direct pull may be more relevant, depending on geometry
Is the application outdoors?	Evaluate the complete construction for temperature, UV, moisture and movement	Indoor requirements may be less demanding

15. Specification Checklist

Before requesting a recommendation or quotation, gather as much of the following information as possible:

• Application: What is the finished product?
• Target surface: What will the magnet attach to?
• Dimensions: Width, length and finished piece size.
• Thickness: Maximum or preferred material thickness, if constrained.
• Load direction: Horizontal, vertical, overhead or moving.
• Air gap: Paint, laminate, vinyl, adhesive or other layers.
• Printing: Printer technology and required surface.
• Adhesive: Substrate and service environment, if required.
• Environment: Indoor, outdoor, temperature, moisture and UV exposure.
• Fabrication: Slitting, cutting, die cutting, laminating or other process.
• Service life: Temporary, repeated use or long-term installation.
• Quantity: Prototype, short run or production volume.

16. Common Selection Mistakes

Mistake 1: Selecting thickness first

Thickness is only one design variable. Start with the application.

Mistake 2: Assuming thicker always means better

Additional thickness can add magnetic capability, but also weight, stiffness and cost.

Mistake 3: Ignoring the target surface

The magnet and target form one magnetic system.

Mistake 4: Ignoring the air gap

Paint, laminates and other layers can reduce magnetic interaction.

Mistake 5: Assuming all magnetic sheets are printable

Print compatibility depends on the complete product construction and printing equipment.

Mistake 6: Assuming all adhesives work on all substrates

Adhesive performance depends on the substrate, surface energy, preparation and environment.

Mistake 7: Confusing magnetic and magnetic-receptive media

The two products play different roles in a magnetic system.

Mistake 8: Skipping application testing

For critical applications, test the actual finished construction under representative conditions.

17. Frequently Asked Questions

What is the best thickness of magnetic sheeting?

There is no universal best thickness. The correct thickness depends on the required holding performance, target surface, air gap, piece size, flexibility, weight, fabrication process and environment.

Should I choose 15 mil, 20 mil or 30 mil?

15 mil is useful when low weight and flexibility are priorities, 20 mil provides a middle ground, and 30 mil can provide greater body and magnetic capability in comparable constructions. The final choice should be based on the complete application.

What is the strongest flexible magnetic sheeting?

Strength cannot be determined from thickness alone. Magnetic formulation, particle loading, magnetization pattern, pole pitch, target steel, air gap and test conditions all influence performance.

What magnetic sheeting should I use for a vehicle?

Use magnetic material specifically suitable for the intended vehicle application and follow the product guidance regarding compatible surfaces, thickness, installation, maintenance and environmental conditions. Do not select vehicle magnetic material by thickness alone.

What magnetic sheeting should I use for printing?

Choose a product specifically compatible with your printing technology, media transport system, required thickness and finishing process. A printable face and equipment compatibility are both important.

What magnetic material should I use for adhesive-backed applications?

Select both the magnetic construction and the adhesive system for the application. The adhesive must be compatible with the actual substrate, temperature, surface condition and service environment.

Can I use thinner magnetic material to save weight?

Yes, if the thinner construction provides sufficient magnetic performance under the actual application conditions. Using the minimum material that reliably satisfies the requirement can reduce weight and material consumption.

Should I use magnetic or magnetic-receptive material?

Use magnetic material when the selected layer needs to create the magnetic field. Use magnetic-receptive material when it needs to be attracted to a compatible magnetic base without necessarily being permanently magnetized itself.

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Safety & Application Reminder

Flexible magnetic material should be tested as part of the complete finished system for applications where detachment could cause damage, injury or loss.

Evaluate the actual target surface, air gap, load direction, printed or laminated layers, adhesive system, environmental exposure and fabrication process before final approval.

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Continue Learning About Flexible Magnetic Materials

Learn the fundamentals in SSKC-026 — Flexible Magnetic Sheeting Explained.

Understand magnetization and pole pitch in SSKC-027 — Pole Pitch and Multipole Magnetization.

Learn about ferrite chemistry in SSKC-028 — Strontium vs Barium Ferrite.

Compare flexible and rigid magnetic solutions in SSKC-029 — Flexible Magnets vs Neodymium Magnets.

Understand magnetic-receptive systems in SSKC-030 — Magnetic vs Magnetic-Receptive Materials.

Compare common material thicknesses in SSKC-031 — 15 mil vs 20 mil vs 30 mil Magnetic Sheeting.

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Need Help Selecting Flexible Magnetic Sheeting?

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