Importance of Surface Preparation
We know that the proper surface preparation is vital for any protective coating system. You can not remove the contaminants like oil, grease, dirt and chemicals and they will prevent adhesion of the first coat. Rust left on surface will loosen the coating and mill scale if not removed completely will accelerate corrosion.
Decreasing : You can easily remove the large amount of contaminates like oil grease with the help of special solvents.
Contaminates are removed by wiping the surface with rags soaked in the solvents followed by wiping dry clean rags.
Hand Tool Cleaning :
Hand Tool Cleaning is carried with the help of wire brushes, scrapes, chipping hammers followed by emery paper to remove loosely adhering rust, mill scale or other contaminants.
If possible power tool cleaning, flme cleaning or blast cleaning is to be done which will better surface for painting.
Surface Preparation On Non-Ferrous Metals
The surface should be cleaned and made oil and grease free. When the surface is galvanized then any white Zink corrosion present can be used for the removal by high pressure water washing or scrubbling.
This removes soluble Zink salt from the surface. The substrates should be then etched primed by using washed primer to facilitate adhesion of the paint film on the surface.
Surface Preparation Of Masonary Surface
Firstly, the surface should be clean dry and free from oils and other contaminates which adversely affect the adhesion of paint. Remembered that any loose contaminates and powder formed on the concrete may result in peeling off the paint film. Surface should be washed with fresh water and dried. The surface should be checked for neutrality and neutralized suitably prior to application.