Painting directly over loose rust rarely provides a durable result. Remove flaky corrosion and unstable material mechanically.
The surface should be free from dust, grease and moisture.
Apply a suitable anti-corrosion primer followed by a finish coat designed for the exposure conditions.
Assess the rust
Remove loose rust, lifting paint and contamination. If corrosion has thinned the metal or damaged a structural component, painting alone is not an adequate repair. Preparation must meet the chosen system's requirements. Use a rust converter only where its instructions and system compatibility allow.
Build the protective coating
After preparation, remove dust and grease and apply the suitable corrosion primer and finish. Avoid gaps at edges, bolts and joints and maintain the specified film thickness. Simply covering rust with thick paint, or treating a specialty product as a universal substitute for preparation, can lead to early failure.
System checklist
- Identify the material and existing finish.
- Distinguish interior and exterior use.
- Read technical and safety instructions, especially cleaning and waste handling.
Is a rust converter always required?
No. Some systems call for another preparation standard and primer. Check converter residue requirements and compatibility with subsequent coats. The complete system instructions, not the product name alone, determine the approach.