Fig. 1 shows the pieces in position and marked for a lap-joint, commonly used in building frame houses; Fig. 2, the upper piece cut to receive the vertical one. In nailing the pieces together, the vertical one is forced up against the shoulder, a, of the horizontal. This shoulder adds to the firmness of the joint, and the rabbet gives more secure nailing. The rabbet for timbers should have about the proportions shown in the figures.

Fig. 3 shows the ordinary rabbeted-joint of boards to be united by nailing. In laying out the rabbet, the mark a, Fig. 4, must be made with try-square and knife, the mark b with the marking-gauge; saw on the mark a with the cross-cut, and then chisel down the rabbet to the mark b. The horizontal piece may project slightly over the vertical, if it is intended to be finished with a plane.

Fig. 5 shows a grooved joint; the groove is marked with try-square and knife, the depth at the ends gauged. It is cut out with saw and chisel. This joint is used where there is apt to be a displacement sidewise, and also to make water-tight structures. In the latter case the groove is made a little narrower than the thickness of the tongue, which is slightly chamfered. The groove and tongue are then coated with white-lead and forced together.

Fig. 6 is a modified form of the grooved joint. Where there is not enough wood beyond the groove to give sufficient strength, the groove may be made smaller, usually half size. It is cut the same as that of Fig. 5, or with a rabbet-plane.

The difficulty of giving a good appearance to joints like Fig. 3 leads to various devices for finishing, the commonest of which is the bead. This is worked on the edge by a plane, the shape of which for cutting a 1/4" bead is shown in Fig. 8; the iron cuts only the depth a, and the round b; the portion c of the sole acts as a stop to regulate the depth, and d as a guide against the edge of the board. The form cut is shown at a, Fig. 9, and is called a single bead; by reversing the plane and cutting on the other side, a double bead is formed, as at b, Fig. 9.

Fig. 7 shows applications of the bead. Although either piece may be beaded, it is customary to bead the tongued edge of a board

Ex. 10.

Fig. 1

Fig. 2

Fig, 3

Fig. 4

Fig. 5

Fig. 6

Fig. 7

Fig. 8

Fig. 9