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Re: New boat finish - failure from below
Boats that originally have 'dark' hull have thicker matting layers under the gelcoat to prevent 'print out' of the subsurface roving layer - 'the bumps' which appear after a newly painted/coated dark hull is exposed to heating in the direct sunlight.
Boats that originally have white or 'light' gelcoat and are later painted 'dark' will usually experience significant 'print out' of the undersurface roving layers when later painted or coated with anything 'dark'.
So, if the boat originally had white gelcoat and someone painted the hull 'dark', this is the leading cause of the development of 'pimples' and other surface discontinuities of the hull surface .... the original polyester in the gelcoat, etc. became 'more' cured due to the increased temperature cause by the 'darker' color that was overlaid upon the original WHITE gelcoat that had a 'thinner' matting layer underneath - quite common with 'painted' fiberglass boats.
Last edited by RichH; 07-10-2017 at 05:50 PM.