Paint adhesion testing

It is helpful in giving relative ratings for a number of coated panels showing significant differences in adhesion.

When the materials have dried, the adhesion is determined by pressing panels under a rounded stylus loaded with increasing weight until the coating is removed from the substrate surface.

The test is done by securing loading fixtures (dollies) perpendicular to the surface of a coating with an adhesive.

The force that is applied gradually increases and is monitored until a plug of coating is detached or a previously specified value is reached.

There are two methods described in the ASTM Specification;[4] An X-cut is made through the film with a carbide tip tool to the substrate.