Will magnetic signs stick to any surface?
Magnetic signs are intended for use on metal surfaces.
We field a lot of questions about magnetic signs on a daily basis from customer curious about purchasing mobile advertising. And one of the questions we do get asked, on occasion, is if our magnetic signs stick to any other surfaces besides vehicles. The answer is yes, as magnetic signs will stick to any surface that is metal. There are lots of other surfaces that are comprised of metal. For instance, there are metal doors, metal garage doors, metal cabinets, metal refrigerators and the like. If it's metal, our magnetic signs will stick to it.
But there are surfaces that look like or resemble a metal surface that are not fully metal. A few examples would be aluminum, plastic or fiberglass. These are a few popular materials that are found on some vehicles and other objects. A lot of tractor trailers, box trucks and regular pull-trailers are made from aluminum because it is a very lightweight material. And while aluminum resembles metal, a magnetic sign will fall right off of anything that is aluminum.
Fiberglass and plastic components are found on a lot of newer vehicles because they are lightweight and rigid enough to be used in place of metal. Take for instance the fiberglass body of a Corvette, which is one of the most well known sports cars still in existence. Another seemingly metal component of a car (unless you have a classic car) is the bumper. And even if the bumper resembles metal, it more than likely is not, and so a magnetic sign will not stick to a bumper. Another hidden problem that some magnetic sign buyers fall prey too is vehicle repair work. If your vehicle has undergone body work that includes "bondo" or any other non-metal body fillers.
The best way to determine if a magnetic sign will stick to a surface is to do a quick and simple adhesion test. Most people have magnets on their fridge of some sort, so grab a fridge magnet, and try throwing that onto the surface that you'd like to put a magnetic sign on. If the fridge magnet sticks without falling off then it's safe to say that the surface is metal. For large surface areas, make sure to spot test the entire area that is intended to house your magnetic sign to avoid any adhesion issues.