Edge Mapping,Shrinkage

Description: Enlarged sand scratches caused by shrinking action of primer layers that held excess solvent into the basecoat or topcoat application, appearing at the area of the repair where it was sanded through to the substrate.


    » “Piling on” the undercoat in heavy and wet coats. Solvent is trapped in undercoat layers which have not had sufficient time to set up
    » Material not uniformly mixed. Because of the high pigment content of primer-surfacers, it is possible for settling to occur after it has been thinned
    » Improper thinner/reducer selection
    » Improper surface cleaning. When not properly cleaned, primer surfacer coats may crawl or draw away from the edge because of poor wetting and adhesion
    » Improper drying. Fanning with a spray gun after the primersurfacer is applied
    will result in drying the surface before solvent or air from the lower layers is released
    » Finishing grit of sandpaper too coarse


    » Apply properly reduced primer-surfacer in thin to medium coats following recommended flash-off time between coats
    » Stir all pigmented undercoats and topcoats thoroughly
    » Select only thinners/reducers that are recommended for existing shop conditions
    » Thoroughly clean areas to be painted before sanding
    » Use proper sandpaper grit before applying polyesters or undercoats
    » Follow product recommendations per
    its Technical Data Sheet


    » Thoroughly dry affected area
    » Sand, isolate if necessary, and refinish

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