Woven Roving (WR) and Chopped Strand Mat (CSM) are fiberglass reinforcement materials used together in composite applications to enhance strength and surface quality. WR is made from continuous fibers woven into a crisscross pattern, providing high tensile strength, dimensional stability. In contrast, CSM consists of randomly oriented glass fibers held together by a binder, offering good resin absorption, flexibility, and a smooth surface finish, ideal for initial and final layers in laminates. Typically,resins are applied first to the CSM to create a smooth surface, followed by WR for structural reinforcement, and then another CSM layer to seal and finish the composite. This combination ensures balanced strength and smooth aesthetics making it popular in boat hulls, automotive panels, and waterproofing applications.
