Touch up paint is not recommended to repair surface scratches on COLORBOND steel. The different weathering pattern of touch up paint will lead to an inconsistent colour across the sheets’ surface. It is recommended that damaged sheets be replaced.
If the COLORBOND steel sheet is only scratched back to the ZINCALUME steel coating, leave the scratch bare as the sacrificial properties of Zinc will produce an oxide to protect the surface from corrosion.
If the sheet is scratched back to the cold rolled metal base and the scratch is greater than 2mm wide, sacrificial protection will be reduced and those sheets should be replaced.
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