wire cloth layers are applied to a screen frame the method may be modified in various ways for example a screen frame may placed in the jig and tensioning and pressing to the screen frame carried out together as described above in respect of fig1 to 3 for example the additional handle members 32 may be omitted and tensioning in the direction of arrows x and z achieved by temporarily locking the roll 28 of wire cloth 1 to prevent unrolling tensioning means are then engaged with the handle members 3 along edge 11 of the wire cloth and activating the tensioning means provides the desired tension between the locked roll 28 and the handle members 3 at the edge 11 fig6 a shows schematically a wire cloth 1 which is being held under tension in orthogonal directions as indicated by the arrows a and b in a pre tensioning apparatus that makes use of a series of clamps and associated tensioning means 34 the clamps bite directly on the wire cloth 1 after tensioning the cloth 1 to the tension used when forming a filtering screen in a jig a single elongate handle member 36 is bonded along each edge of the wire cloth 1 the pre tensioning ensures that the wire cloth is not creased after attachment of the elongate handle members 36 the wire cloth is released from the clamps and tensioning means 34 the wire cloth 1 with handle members 36 attached can then be placed in a jig for tensioning and bonding to a screen frame.