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Origin and Potential Causes:
· Use of incompatible materials. Solvents in new topcoat attack old surface which results in a distorted or wrinkled effect.
· Insufficient flash time. Lifting will occur when the paint film is an alkyd enamel and is only partially cured. The solvents from the coat being applied cause localized swelling or partial dissolving which later distorts final surface.
· Improper dry. When synthetic enamel type undercoats are not thoroughly dry, top coating with lacquer can result in lifting.
· Effect of old finish or previous repair. Lacquer applied over a fresh air-dry enamel finish will cause lifting.
· Improper surface cleaning or preparation. Use of enamel-type primer or sealer over an original lacquer finish which is to be topcoated with a lacquer will result in lifting due to a sandwich effect.
· Wrong thinner or reducer. The use of lacquer thinners in enamel increases the amount of substrate swelling and distortion which can lead to lifting, particularly when two -toning or re-coating.
· Application of coats too heavily.
· Excessive film build
Prevention Techniques:
· Avoid incompatible materials such as a thinner with enamel products, or incompatible sealers and primers.
· Don't pile on topcoats. Allow sufficient flash and dry time. Final topcoat should be applied when the previous coat is still soluble or after it has completely dried and is impervious to topcoat solvents.
· Select thinner or reducer that is correct for the finish applied and suitable for existing shop conditions.
· Solvent test and remove or isolate solvent-sensitive substrates.
· Avoid excessive film thickness.
Remedy:
Remove finish from affected areas and refinish. In very severe cases the whole paint system must be removed to the substrate and be refinished.
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