Top grade plywood panels suitable for exterior usage are becoming increasingly scarce and expensive so that it is desirable to convert low-quality plywood panels into higher quality products suitable for external uses. Fiber-clad plywood panels having the purpose of upgrading lowquality panels are disclosed in my prior U.S. Pat No. 3,669,783, issued Mar. 13, 1972, which relates to a method for forming a flat-surfaced plywood panel with a printed paper surface and intended for decorative interior usage.
My prior U.S. Pat. No. 3,661,688, dated May 9, 1972, relates to a grooved panel but the core consists entirely of wood shavings or the like in which grooves are formed. While the particle board, as disclosed in the last mentioned patent, has met with considerable commercial success, much is left to be desired because such a particle board paneling lacks the structural strength of a plywood panel of comparable thickness.