The top and bottom shapers, indicated in Fig. 250, are in their positions during use, which is that of shaping hexagonal nuts and bolt-heads. The gaps in such implements are of various sizes to produce hexagons of the required dimensions, so that each pair of shapers produce a hexagon of one size; and either pair may be selected and keyed to the hammer and anvil at any time when required.

The method of using such implements consists in placing a nut, while on a mandril, between the shapers, and hammering the work until the two faces, marked with F, strike each other, at which time the nut is of correct diameter; after which it is cut to a proper length with chiselling, if necessary.

To shape a bolt-head or other hexagonal boss in the mid-part of a piece of work, the component pieces may be piled together, or a collar wrapped around the bolt, to produce a lump of sufficient thickness; after which, a welding heat is given to the lump, and the hexagonal form produced with two or three blows while in the shaping gaps. The head or boss being thus partly formed, it is next completed by trimming the shoulders with a set hammer and with a chisel, that the head may be of proper length.

When two such hexagon shapers are employed for bolt-making, two or three blows are first given to the collar for the head, or pile, if a pile is used instead of a collar, and it is thus thoroughly welded to the bolt-stem; this stem is next put into a heading tool to square the shoulder, and also the upper extremity of the head; and the bolt-head is afterwards finally reduced with a few blows in the shaping gaps. To make a number of bolts by such means, ail the component pieces are cut to the exact dimensions, to avoid cutting off superfluous pieces during forging. The precise quantity of metal required is known by ordinary measurement, and by finishing one or two previous to the entire number.

Cranking Blocks

The shaping implement indicated by Fig. 252, may be used as a top tool or as a bottom tool, and the corresponding tool possesses a groove which is of the same outline as the groove in the block shown by the Figure (252). These grooves are half round, and their width equals the diameter of the iron or steel to be cranked. The height of the hump in the mid-part of the tool is sufficient to make the throw of the crank to the desired length. Such blocks are, therefore, especially adapted to bend straight pieces of round iron or steel, so that the crank-arms and crank-pins shall be of a well-defined outline throughout.