There is described an apparatus (1) for coating a cylinder (C), in particular a wiping cylinder of an intaglio printing press, with a plastic composition comprising inter alia a blade mechanism (4) comprising a single substantially planar blade (40) with a straight edge (40a) extending along the full length of the cylinder to be coated and which is mounted rotatably about an axis parallel to the axis of rotation of the cylinder to be coated. The blade comprises, at its terminal end proximate to the cylinder, an inclined end portion (4a) having an inverted-V shape rising from the upper side of the blade, the top edge of the inclined end portion forming the straight edge of the blade. The blade is adapted to be rotated so that the straight edge of the blade undergoes an upward movement substantially tangential to the periphery of the cylinder in order to discontinue the application of the plastic composition onto the surface of the cylinder.