mounted on the traverse mechanism of the lathe for movement in the direction of the path 14 parallel to the axis 11 of the workpiece further details of the lathe and the mounting for the rubber applying head in the lathe will be described with reference to fig6 and 7 the rubber applying head comprises a main support frame 15 formed with a threaded bore 16 to receive a fixing bolt mounted on the cross slide of the lathe as described later a horizontal limb of the frame 15 has a pair of spaced brackets 18 extending towards the workpiece axis 11 between which a tapered feed roller 19 is mounted for rotation on an axle 20 supported at its ends in the brackets 18 the feed roller 19 is intended to apply a supply of rubber to the workpiece as will be described later the frame 15 has an upright limb formed with spaced horizontally extending slots 17 to which a sub frame 21 is secured to permit the sub frame to be adjusted towards and away from the workpiece axis 11 with respect to the main frame 15 on the side of the sub frame adjacent roller 19 there is a projecting stub axle 22 on which a main roller 23 for pressuring and rendering plastic the rubber coating applied to the workpiece by the roller 19 to masticate and compound the layer to form a homogeneous layer of the required thickness around the workpiece again as will be described later at the forward end of the sub frame 21 there is a curved tapered pressure surface 24 for bearing on the rubber layer immediately next to the roller 23 a retractable plough 25 projects from the surface of the pressure.