Process for the manufacture of multi-ply panel boards preferably for floors

A process for the manufacture of multi-ply panel boards comprising the steps of:

• gluing a first tread ply with a first crossband ply, said first tread ply consists of a plurality of adjacently lying wooden boards with respectively longitudinally running fibers, said first tread ply forms a visible or tread surface, said first cross band ply consists of adjacently lying wooden boards or slats, fibers of said first crossband ply are disposed parallel to the first tread surface and perpendicular to fibers in the first tread ply;
• gluing a middle ply, matching the first tread ply in material and fiber grain onto the first crossband ply;
• forming a second crossband ply by matching the first crossband ply in material and fiber grain;
• gluing the second crossband ply onto a free surface of the middle ply;
• gluing a second tread ply matching the first tread ply in material and fiber grain onto a free surface of said second crossband ply to form a composite sheet;
• sawing the composite sheet into double board blanks, a size of which in respective tread surface corresponds approximately to that of panel boards;
• and
• halving the double board blanks to form the panel boards, by a parting cut guided in a middle plane between the two tread surfaces.

A wooden composite sheet for manufacture of panel boards comprising:

• a first tread ply consisting of a plurality of adjacently lying wooden boards, fibers of said first tread ply respectively run longitudinally;
• at least one crossband ply of adjacently lying wooden boards or slats, said first tread ply and at least one crossband ply joined together;
• and
• a second tread ply which is provided on a side of the joined first tread ply and the at least one crossband ply, said second tread ply facing away from the first tread ply, said first and second tread ply and said at least one crossband ply forming a composite sheet, wherein the first and second tread plies and the at least one crossband ply, in terms of fiber grain, dimensions and condition, are symmetrically disposed relative to a middle plane of the composite sheet.