These are made in a variety of shapes and with solid or welded eyes, the general method of making the eyes being exactly as described before under Eye Bolts. A common shape is shown in Fig. 69. The stock is forged into shape similar to Fig. 70 before being bent. To determine the length A the drawing is measured in the same way as described in making the gate hook. The weakest point in most hooks is the part lying between the lines marked xx in Fig. 69. This part of the hook should be heavier and stronger than the other parts. When a strain is put on the hook, there is always a tendency to straighten out or to assume the shape shown by the dotted lines. When forging the hook into shape, the dimension B, Fig. 70, should be made such that the heaviest part of the hook comes in this weakest point. After the hook is entirely forged to size, it should be bent into shape. Hooks are also made from round and from square iron. When made for hooking over a link, and so shaped that the throat or opening is just large enough to slip easily over a link edgewise, but too narrow to slip off of this link down to the one which, of course, is turned at right angles, the hook is known as a grab hook.
Fig. 69. Chain Hook.
Fig. 70. Hook before Bending.