Abstract: The invention relates to a stationary supporting member for the drainage wire belt of a paper machine. The supporting member has a transverse head board with a doctor-like leading edge which contacts the underside of the wire belt. The head board is formed from hard material, which has a drainage area forming a small, variable angle of inclination with the direction of travel of the wire belt. Two C-beams support the head board, one secured rigidly in the machine and the other, which carries the head board, being hinged to the rigid beam. An adjusting board on the rigid beam and having several adjustable stop surfaces distributed over its length, engages stops on which the movable beam is supported. The two beams are clamped together by means of an inflatable hose between the arms of the beam.