Problem Solving Forum
June 27 - July 4, 2011
What steps must be taken to mitigate poor adhesion over an existing aged silver aluminum paint? What primer will achieve good adhesion?
Jose Avendano of KTA-Tator, Inc. on
June 27, 2011:
Which ever surface prepar ...read more Which ever surface preparation method you choose to enhance the bond, you must apply a test patch of the paint system to verify proper coating adhesion. You can use high pressure water cleaning and dull by sanding, but remember, check compatibility with ASTM D3359.
friday Aigbekhai of Nigerdock on
June 26, 2011:
High pressure ...read more High pressure wash the surface; abrade the surface to activate it or sweep blast it; and apply surface-tolerant epoxy or a mastic primer.
Bill Mann of United Coatings on
September 2, 2011:
Some of these aluminized ...read more Some of these aluminized paints will "leaf," even after being pressure-washed, which can result in a poor bond of the of the subsequent topcoat. I'd recommend a low-viscosity, penetrating epoxy primer be applied after cleaning, which will help minimize potential leafing of the aluminum.
Anand Karamandi of Wasser Coatings on
September 3, 2011:
Surface preparation of SSPC SP2 or SP3 is preferre ...read more Surface preparation of SSPC SP2 or SP3 is preferred, if SP6 or SP7 is not possible. A good coat of epoxy mastic at 5-6 mils DFT should be fine. If exposed to UV, a coat of urethane is recommended. Alternatively, a 100% epoxy penetrating sealer can be applied at 1 to 1.5 mil DFT, with solvent cleaning as surface preparation and a necessary topcoat can do a pretty decent job.
Car F. of Municipal City on
August 30, 2011:
I would ask why was the a ...read more I would ask why was the aluminum paint used in the first place. There may be a thermal transferring consideration or a thin film requirement, such as heat radiators or similar devices. Once the question is answered, I would apply the suggestion of the prior commentators.
Shrikant Naik of Asian Paints Limited on
August 25, 2011:
Thorough abrasion of the ...read more Thorough abrasion of the paint surface to remove loosely adherent paint film, followed by water wash to remove soluble salts and other contaminants, if any. The surface can then be coated with conventional alkyd-based coating or a surface-tolerant epoxy mastic.