What should be done to the surface before applying a varnish for corrosion protection?

Cleaning the surface before applying a varnish for corrosion protection is essential to ensure proper adhesion and effectiveness of the protective coating. A clean surface removes any dirt, grease, oils, dust, or previous contaminants that might interfere with the bond between the varnish and the substrate. If the surface is not adequately cleaned, it can lead to issues such as bubbles, peeling, or premature failure of the coating, allowing corrosion to develop underneath.

While other processes may play a role in the overall preparation of a surface for protection, the immediate priority is to ensure cleanliness. This step is fundamental in any coating process, as it sets the foundation for the subsequent application of protective layers, such as varnishes or primers.