A fibrous panel is molded in two or more progressively formed mold members each comprising a porous support plate to which a plurality of rigid mold pieces are affixed. The mold pieces are truncated 3D tapered structures, and are arranged on the support plate in a regular array so that an intersecting grid or lattice of channels is defined between them. A fiber stock is poured into a first mold member and the stock is compressed and dewatered to form a panel. The panel is removed from the first mold member and placed into a second mold member having narrower and shallower channels whose side walls are more upright than those of the first mold member. The panel is further compressed and dewatered in the second mold member, and is densified in both the vertical and lateral directions by virtue of the progressive formation of the mold members.