One method shown in Figure 1. To obtain the lines on a square stick where the corners should come when converted into an octagon or eightsided stick: Lay the square on the one side of the square stick at such an angle that the end of the square will come exactly at the edges or corners of the stick, make a dot on the 7-inch mark and at the 17-inch mark. Through these dots gauge or mark a line parallel with the edge of the stick. Continue this operation on all of the four sides. This gives the lines for the corners of an octagon. In making a flag-pole or spar for a boat or to round any large stick this is the operation used by all mechanics doing the work by hand. THE MITER BOX Of all homemade devices, one of the most frequently used in the shop is the miter box. After FIGURE 5A the box is put together it is a simple problem, with the use of a steel square, to make the cuts necessary to intersect two pieces of wood, as shown in Figure 2. First, the box must be straight and true and the sides form a perfect right angle or square with the bottom. Lay the steel square on the top of the box so that the 12-inch mark on the blade and the 12-inch mark on the tongue will both come FIGURES 2 AND 3 FIGURES 5 AND 4 This gives the angle of a perFigure 3 shows exactly on the edge of the box. miter cut of the intersection of the fect square, as shown in Figure 2. the manner of placing the square on the box to give the desired angle. A sprung molding, which is a molding not solid on the back, as shown in Figure 4, must be placed in the box bottom side up as shown in Figure 5, so as to get a solid bearing to hold it. Cuts in the box to miter around an eight-sided figure or an octagon, as shown in 5A, can be obtained by using 7 inches and 17 inches, marking the cut on the 7-inch side, as shown in Figure 5. TRUING THE SQUARE After obtaining a steel square, the first and most essential thing is to test or prove it to see that it is accurate, forming the angle of a perfect square. FIGURE 6 Take a board planed on one side and straighten one edge of it perfectly as described under Making a Straight Edge. Make a mark across this board with the square, as shown in Figure 6, Position A, then reverse the square to Position B. If the square is true it should exactly fit the mark made. It is necessary to work very accurately, making the mark with the point of a knife and having the edge of the board absolutely straight. If the square is found to be out or inaccurate, it is not necessary to throw it away; it can be made true by a simple method by any handy mechanic. If you do not possess an anvil, make a substitute by To Open the To Close, the FIGURE 7 sticking the ax into a chopping block, lay the square on the head of the ax so that the bearing will come from the throat or inside angle to the heel or outside of the square. To close up the angle, strike with a hammer a sharp blow at a point near the heel; to open the angle, strike near the throat at a point indicated in Figure 7. Don't strike too hard. Use a bell-face nail hammer and the dent will not be noticed. A STRAIGHT EDGE In connection with the work with the steel square a straight-edged board is necessary to have ready for immediate use. Procure a board 8 or 10 feet long of good, dry pine, free from knots and 6 to 8 inches wide. Plane the edge until it seems FIGURE 8 straight to the eye, then lay it on the bench or on another board and make a mark along the edge, just straight with a fine lead pencil; reverse it or turn it over and fit it to the other side of the pencil line. This multiplies any inaccuracy or deviation from a straight line. Make a new line each time you plane the edge. Work with as long a plane as you have and set the blade to take a fine shaving. When the edge will fit both sides of the line made from it while in one position, it is straight. Figure 8 will give a clear idea of this operation. RAFTERS The common rafter for a pitch roof is easily laid out with the steel square There are many methods, |