Problems arise through natural warping when large wooden surfaces have to be made. The usual methods for overcoming these problems are not suitable when the surfaces are required to be completely flat as in the case of panels to receive paintings. Before the advent of ply or composite boards, the traditional practice was to construct panels with taper-dovetail battens housed into their reverse sides. The author describes how these joints were, and still are, cut in Germany. He illustrates the special tools used, together with some examples of such panels. -- AATA