Patent ID: 8429872

Claim:
A method of making a floorboard, comprising: affixing a surface layer on a wood fiber based core to form a floor element, then cutting the floor element into floor panels, such that each floor panel includes an edge portion formed by an edge part of the core and an edge part of the surface layer affixed to the core's edge part, wherein a top face of the surface layer forms a floor surface lying in a horizontal plane, then applying pressure on a portion of the top face defined by the surface layer's edge part with a compression tool having a predetermined profile such that the core's edge part is compressed and said surface layer's edge part is permanently bent out of said plane, wherein said edge portion of said floor panel obtains an edge profile corresponding to the predetermined profile of the compression tool, with said portion of said top face defined by the surface layer's edge part being disposed under said plane, and then forming a mechanical locking system at the edge of the floorboard, wherein the surface layer extends to an outer edge of the compressed edge part, wherein an edge groove is formed at the edge of the floor panel before compression.