Why Won't My Magnet Sign Stick? November 06 2025, 0 Comments

If you’ve ever tried to stick a magnetic sign onto a vehicle only to find that it simply won’t hold, you’re not alone. Many modern cars, vans and pickups now use non-magnetic materials in their body panels to reduce weight, improve fuel efficiency and increase corrosion resistance. That’s great for manufacturers — but not so great for anyone using magnetic vehicle signs.

Traditional magnets only stick to ferrous steel. They won’t stick to:

  • Aluminium

  • Fibreglass

  • Plastic / composite panels

  • Carbon-fibre parts

Below, we’ll cover which vehicles use these materials, why magnets fail on them, and how Gripper Mats provide the perfect solution.

Materials magnets won’t stick to (and why)

Aluminium:
Increasingly used in doors, bonnets, boot lids and even entire vehicle bodies. Aluminium has no iron content, so a magnet simply cannot create a magnetic bond.

Fibreglass / composite (SMC):
Sports cars and performance vehicles often use fibreglass or structural composites for weight reduction and strength — again, not magnetic.

Plastic & carbon fibre:
Many modern bumpers, tailgates, rear quarter panels and trims are plastic or carbon-fibre reinforced. Magnets won’t adhere to these surfaces at all.

Vehicle brands and models where magnetic signs commonly fail

Because of their construction, the following vehicles (and many others) often cannot hold magnetic signs on certain panels:

  • Ford F-150 (2015–present) – aluminium body panels

  • Jaguar XJ (2010–2019) – all-aluminium body

  • Audi A8 – high-aluminium content body structure

  • Tesla Model S and Model X – extensive use of aluminium body panels

  • Chevrolet Corvette (all generations) – fibreglass/composite exterior panels

Many other modern vehicles use mixed materials, meaning even if most of the car is steel, the specific panel you want to attach a magnet to might not be.

Why magnets fail on these vehicles

Magnets need iron to complete their magnetic circuit. Aluminium, fibreglass, composites, plastics and carbon fibre contain no iron at all. So your magnetic sign acts like it’s being placed on glass — it simply won’t grip.

The ideal solution: Gripper Mats

Gripper Mats are specially designed, reusable, adhesive-free pads that allow your magnetic sign to cling securely to non-magnetic vehicle surfaces. Instead of magnetism, they use a high-friction, paint-safe material that holds your sign firmly in place.

Benefits of using Gripper Mats

  • Work on any non-magnetic panel — aluminium, fibreglass, plastic and even glass

  • Paint-safe and residue-free — no adhesives, no glue, no marks

  • Reusable and washable — rinse with water to refresh the grip

  • Customisable — easily trimmed to match the size of your magnetic sign

  • Reliable grip — tested by tradespeople, fleet users and sign installers on modern vehicles where magnets won’t stick

How to use them

  1. Clean and dry the panel and the back of your magnetic sign.

  2. Apply several Gripper Mats evenly across the back of the sign — especially at corners and edges.

  3. Press the sign firmly onto a flat, smooth panel (avoid deep curves or panel gaps).

  4. To remove, peel slowly from a corner.

  5. Rinse the mats and let them air-dry so they’re ready for next time.

When Gripper Mats are especially useful

  • Aluminium-body pickups, vans and EVs

  • Vehicles where adhesive vinyl graphics are not allowed (e.g., rental or lease vehicles)

  • Sports cars with fibreglass or carbon-composite panels

  • Businesses needing temporary or removable branding

Final thoughts

If your magnetic signs aren’t sticking, the problem isn’t the magnets — it’s the vehicle. With so many modern models made from aluminium, fibreglass and plastic, magnetic signs simply can’t grip like they used to. Gripper Mats provide a simple, safe and effective solution, letting you keep using your existing magnetic signs on any vehicle, regardless of what the panels are made of.