Page:Cassells' Carpentry and Joinery.djvu/317



Introduction. — A rod stands in the same relation to a craftsman as a scaled drawing does to a designer. In most shops the work is done by a setter-out, who makes his drawings from full-sized details prepared by the architect. The most convenient size of rod for general use is about 10 ft. by 11 in. by ⅝ in., but a varied stock should be kept. Rods should be of pine, free from shakes and loose knots. Pine is chosen on account of its softness and evenness of grain, which enables lines of equal firmness, and not easily erasable, to be drawn. The boards should be nicely smoothed, whitened over, and rubbed with fine glass-paper to produce an even surface. The edges should be kept square. For making drawings on the rods, squares with 6-in., 12-in., and 36-in. blades, a trammel, dividers, pencil compasses, and a five-foot rule, will be found most useful

Fig. 936, Rod 1 (scale = ¾ in. to 1 ft.), shows the plan of a ledged and beaded door, in a 4½-in. by 3-in. rebated and beaded frame, fixed in a 4¼-in. wall. (Fig. 937 shows a section of the door and frame, and will be referred to later.) This kind of door is generally used for outhouses. First lay the rod on the bench and draw a line parallel to the front about 1 in. from the edge, which will represent the face of the wall. At a distance of 4½ in. from it draw a parallel line to represent the thickness of the wall. As plaster is not required, the framework will be of the same thickness, an opening 3 ft. wide being made in the brickwork to receive it. The lines meet at. The two posts are next filled in, the outside of the frames being marked off ½ in. less than the opening, which saves scribing, as the brickwork is always more or less rough. Fig. 938 shows a mould of a wood jamb or post used in Fig. 936. If several patterns of moulds are kept in stock, much time will be saved in setting out. A space of 2 ft. 6 in. is required in the clear of the frame, the posts being 2¾ in. when planed, and a 3-in. jamb is allowed for. A line is next drawn joining the rebate at each end, as shown, the thickness of the door and a depth of ½ in. being included. The space between the two jambs is divided into five equal parts, the two outer boards which fit into the rebates being ½ in. wider than the others, so that they show equal on the face. On each side of the tongued edge at the boarding joints a tongue and bead is in. The projection marked (Fig. 936) represents the ledge on the back, forming a rail to which the boards are fixed. It is made 1⅛ in. thick, with a ⅜ in. chamfer. Where possible, an elevation is drawn at one end of the plan rod, as shown at Fig. 936 (enlarged at Fig. 939), for general guidance. The rod is turned over and the height drawn in section (see Fig. 937). Parallel lines 4½ in; apart are drawn as before, is squared across, and the head filled in with the mould shown in Fig. 938. From a a set down 6 ft. 9 in., the height required, which gives a 6-ft. 6½-in. door. The ledges or rails are filled in as shown, the middle one being 3 ft. from the bottom, the lower one 1 ft. from