What is the difference between adhesive force and shear force / displacement force?

A common application for magnets is attaching objects to the wall. In this regard, we very often receive enquiries about how high the adhesive forces should be.

Firstly, a brief note: All adhesive forces (holds x kg) specified by us always refer to the tensile direction (perpendicular to the contact surface).
However, if the load force acts parallel to the contact surface (shear direction), the maximum value is significantly lower. This is the case when objects are attached to the wall using magnets.

Force parallel to the contact surface (shear force)

When hanging objects on the wall, the force (the weight of the object to be hung) acts parallel to the contact surface, i.e. in the direction of shear. You may have noticed that it is much easier to push a magnet sideways than to pull it away vertically. The forces in this direction are significantly smaller and depend on a number of factors:

- Holding force of the magnet
- Material and surface properties: in the case of rough surfaces, or


As a rule of thumb, when attaching a neodymium magnet to a metal surface (with direct contact), for example, you can say that approx.
For example, if you want to attach an object weighing 1 kg to a wall (iron), you would need approximately one magnet with an adhesive force of 8 kg (or 4 magnets with an adhesive force of 2 kg each).

If you want to test/measure/experiment with adhesive forces and shear forces yourself, magnets from our neodymium magnets category are best suited for this.