A simple tool that is frequently called for is the S-wrench. This wrench is usually made with a gap at each end suited for nuts of different sizes. It is shown complete in Fig. 114. The jaws at the end should be parallel with each other. A line drawn from one pair of jaws to the other should make an angle of 30 degrees with the center line of each. There are two ways in which such a wrench can be forged. One is to forge the jaws separately and then weld to the handle. In the other the jaws are cut from a solid piece of metal and the iron between is then drawn down to the proper size for the handle. The latter is preferable, since it avoids all welds.
To make the wrench by the second process, select a piece of steel large enough to form the head. Fuller it down back of the head as shown in A, Fig. 115, at a a. Round the end and punch the hole b. Next treat the other end in the same way and draw out the intermediate metal giving the form shown at B. Now cut out the holes b b securing the form shown at C. It now remains to bend the heads to the proper angle and to give the desired curve to the shank. In forging such a wrench the outer edges should be slightly rounded so that they will not cut the hand. The inside of the jaws should be perfectly square with the sharp edges; this finish can best be obtained by filing.
Socket wrenches are made in several ways. The easiest way in "hurry-up" work is the method illustrated in Fig. 116. A stub is forged to the same size and shape as the finished hole is to be, and a ring, bent up of thin flat iron, welded around this stub. When finishing the socket, a nut or bolt head of the same size as that the wrench is intended to fit should be placed in the hole and the socket finished over this, between swages. A better way of making wrenches of this kind is to make a forging having the same dimensions as the finished wrench with the socket end left solid.
Fig. 114. Forged S-Wrench.
The socket end is then drilled to a depth slightly greater than the socket is wanted. The diameter of the drilled hole should be, as shown in Fig. 117, equal to the shortest diameter of the finished hole. After drilling, the socket end is heated, and a punch of the same shape as the finished hole is driven into it. The end of the punch should be square across and the corners sharp. As the punch is driven in, it will shave off some of the metal around the corners of the hole and force it to the bottom, thus making it necessary to have the drilled hole slightly deeper than the finished socket.
Fig. 115. Steps in Making Wrench.
Fig. 116. Socket Wrench.
Fig. 117. Making Hole in Socket Wrench.