Bossing tools are adapted to shape bosses of levers or rods that are either round or flat. A bottom bossing tool for round rods is shown by Fig. 228 ; a tool of this class is useful for shaping several varieties of joint bosses. Fig. 229 denotes a bottom shaper for eccentric-rod bosses that are forged without gaps; also for shaping a large class of lever bosses, including weigh-shaft-levers, lifting-levers, reversing-levers, crank-levers, and others of similar shape. A flat rod or lever having one or more bosses extending from only one side of the lever, instead of from two opposite sides, may be shaped by being hammered into the bottom tool, a top bossing tool not being required. Such a bottom tool will shape also lever bosses that extend from two opposite sides of the lever, if both bosses are to be of one diameter, and are to extend to an equal distance on both sides. But to shape a boss which is larger in diameter at one end than at the other, or is not of the same length at one side of the lever as at the other, two tools are required, top and bottom; and when a number of bosses are wanted at one time, the tools should be guided or jointed together.

The diameter of the metal selected for making a lever boss may be sufficient to allow the boss to be formed without any previous upsetting. Such a piece will need therefore a reducing, to produce the arm or lever which is to extend from the boss. This reducing is effected at the beginning of the forging ; after which the boss part is roughly formed with fullers and chisels, and the work finished with the bossing tools.

Such shaping implements will also form bosses that are made by piling; being piled up on one side or on two sides of a lever; this lever portion being of the forged dimensions previous to attaching the bosses, that the bossing tools may not be required to shape anything more than the bosses.

To make a boss at one end of the lever, the iron may be cut partly through in several places and doubled and welded together until a lump of sufficient thickness is obtained. When enough metal is accumulated by this method, the boss lump is heated to welding and shaped by the tools at one or two heatings.

When these methods of piling and doubling are adopted for making bosses in large numbers, it may be necessary to cut the component pieces to a proper length, previous to commencing the formation of the bosses. For this purpose, the smith can ascertain the sectional area of the boss required, and also its length; and having also discovered the sectional area of the bar or rod which he is to make into the boss, he may know the length of bar necessary to be piled or doubled for one boss, by applying the appropriate rule (page 8). This rule is equally applicable whether the original piece is larger than the intended work, or whether iron of smaller diameter is to be used, and upset or doubled to the needful dimensions. After thus discovering the exact amount required for one boss, the proper amount may be added for welding and burning during the several heatings.