Fibreglass panel laminating sheet machine

producing fiber-reinforced resin panels with a gelcoat-type protective cover layer where the freshly impregnated fiber layer covered by film is first heated until the resin gels, where upon the cover film is peeled off and a protective layer of similar resin or of unrelated lacquer is applied to the gelled resin-impregnated fiber layer and the laminate is cured to harden.

Special method to improve the surface of cured, fiber-reinforced resin panels through the application of an additional layer of resin, the method being generally referred to as a "gelcoat method."  It is based upon the experience that in the process of producing fiber-reinforced resin panels some fibers will come to be positioned very close to the panel surface so that only an extremely thin layer of resin will be covering them. According to British Pat. No. 899,307, which likewise teaches a gelcoat method, it may even happen that some of the fibers protrude to the panel outside (Page 1, lines 19-21). Even where there remains a thin resin film on top of those fibers which are close to the panel surface, this thin film is easily destroyed through wear or through the influence of weather conditions. The results may be discoloration of the translucent panels, with a consequent reduction in their light permeability, due especially to possible soilage of the exposed fibers. The basic contribution of the gelcoat method is its suggestion of applying to the fiber-reinforced, not yet fully cured resin panel a pure.