Make Your Ridge-Plank and Rafters
now, while the floor is clear of rubbish.
Lay out and mark on the floor, with a carpenter’s soft pencil, a straight line, four feet long (A B, Fig. 70). At right angles to this draw another line, three feet six inches long (A D, Fig. 70). Connect these points (B D, Fig. 70), with a straight line, then complete the figure A B C D (Fig. 70). Now allow two inches at the top for the ridge-plank at B, and two by four for the end of the side plate at D. You then have a pattern for each rafter with a “plumb-edge” at B and a “bird’s-mouth” at D. The plumb-edge must be parallel with B C, and the two jaws of the bird’s-mouth (Fig. 71) parallel with D C and A D, respectively. Make six rafters of two-by-four-inch wood, one ridge-plank of two-by-six or seven-inch wood.
Figs. 70 and 71.