Abstract: A hollow panel including a hollow central board or body and two external sheets forming a sandwich, the central body being made of wod fiber and glues and made in a mold, the mold having an uneven surface with oblique walls and truncated vetices where, the external sheets, made form the same material as the central body, are joined using the same glues, and the mold has a fixed peripheral frame, a thrust platform and a heating plate with a serrated plate to which another, similar plate is brought close—such that the two serrated plates constitutes the mold, where—the latter plate is ridigly secured to the upper hot plate of the press for forming the cnetral board or body, and the teeth of the two plates are offset in a staggered pattern, and do not meet, to form the uneven surface with the desired thickness.