Upholstery of spanking furniture
Most items of modern spanking furniture are upholstered where the weight of the spankee rests on. For this reason, the art of upholstery has been learned (or improvized) by many hobby constructors of spanking furniture.
Simple uphostery is comparatively easy today: a wooden board can be used as a platform to which the padding is added. Foam material (e.g. polyurethane) is cut to the required size and glued or stapled to the board. Then a cover of leather, synthetic leather, PVC or fabric is stretched over the foam and board, and fastened to the underside with staples or nails. The corners require special attention (folding in of the cover or sewing) unless the cover is very elastic.
More sophisticated upholstery uses metal springs and various other techniques. Before the invention of synthetic foams, natural materials were used for upholstery such as dried grass, straw, animal hair, or wool.