What term describes a warp across the width of the face of wood, with edges higher or lower than the centre?

What term describes a warp across the width of the face of wood, with edges higher or lower than the centre?

• A. Design for assembly
• B. Creep
• C. Density
• D. Cupping

Answer: (D)

Cupping is a warp across the width of a wood face where the edges are higher or lower than the center. It happens when moisture movement or uneven drying causes one face or edge to shrink or swell differently from the opposite side, curling the surface across the width. This is distinct from warps that run along the length, and from terms like creep (deformation under sustained load), density (mass per unit volume), or design for assembly (a design consideration, not a wood warp).

Cupping is a warp across the width of a wood face where the edges are higher or lower than the center. It happens when moisture movement or uneven drying causes one face or edge to shrink or swell differently from the opposite side, curling the surface across the width. This is distinct from warps that run along the length, and from terms like creep (deformation under sustained load), density (mass per unit volume), or design for assembly (a design consideration, not a wood warp).