A step-ladder, or pair of steps, as it is otherwise called, is an important item of the household equipment which any amateur joiner of fair skill can easily put together.
For the sides are wanted two 4-foot 3-inch lengths of wood measuring 4 inches by $ inch after planing. The top, A, is 18 inches by oi inches by – inch. The treads or steps are of 4-inch by -inch board.
The carpenters bevel is rsed to draw lines near the ends of a side at an angle of 65° to what will be the front edge. The lines are 4 feet apart. Cut off top and bottom, and work oil the second side from that cut first. The two sides are now clamped together and a line is squared across their front edges 6i inches from the top; and below this four other lines, 8k inches apart. Below each of these five fines rule a second, inch away from it. The boards are then separated, and the ten marks used to rule lines across what are to be their inside faces, at an angle of 65° to the front edge, and therefore parallel to the top and bottom lines.
Cuts are sunk just inside the lines to a depth of ½ inch with a tenon saw blinded by strips overlapping its ends and screwed together, so that it cannot enter more deeply. The waste between the pairs of cuts is chiselled out, or removed with a router, and the grooves to take the ends of the five treads have been formed.
After rounding off their corners, so as not to hurt the board, lay the sides on edge on the floor, on either side of a centre line, from which their top ends should be 8 inches (measuring to the outside) and their bottom ends 9 inches. Having got the position correct, and the tops in a lino square with the centre line, tack pieces across the ends, and blocks to the floor to prevent spreading. Then cut the pieces for the top and bottom treads, as measured from the bottom of the grooves. The back of each tread is bevelled to an angle of 65°; and the front edge is rounded off and sloped a little at each end to meet the sides, beyond which it projects a little. Slide the treads into place (they should be a tight fit) and secure them to the sides with two long screws at each end. The middle tread is then fitted; and finally the remaining two.
The ladder is then turned over for the hinge-piece B to be screwed on. The top, A, can then be attached. This is rounded in front and at the ends.
The back frame, F, is composed of two side-pieces, -lOi inches by 2 inches by inch, connected at the top by a piece 3 ½ inches wide, and 4 inches from the bottom by a bar 2 inches wide. The bars are tenoned to fit mortises in the sides. The exact positions of the tenon shoulders, and their correct angles can best be got by tacking the sides to the back of the ladder, and then marking off. The tenons are held by wedges driven into them.
The butt hinges holding the back to B are arranged to have one bottom screw in a side and the other in the top bar, and so hold the parts together. Holes are bored in front and back for the cords which limit spreading to 36 inches at the the inner edge as the bottom of the step bottom, measuring from outside to outside. Grooves.
When open it is 2 feet high, cut, a beading is formed on the front of There are three treads on each side, the each side, with its groove as far in from top ones together forming a tread of double width when the steps are opened. The materials are ½ inch thick; the sides 3 inches wide; and the treads 3½ inches wide. At the bottom the steps have a 22-inch spread overall.