These "gouges" or "hollow sets " are struck by the sledge, the smith holding the tool by the withy handles, while the striker directs his blows on the head. The bevel is either inside or outside; and when cutting through a thick mass of iron, it is necessary to withdraw them occasionally, and dip them momentarily in water to prevent softening and loss of temper.
Besides these there are a large number of non-cutting tools of different forms. Chief among these is the "fuller," used, as its name implies, for "fullering" or drawing down iron in a series of grooves, for welding, or for obtaining a flat surface, or for producing a starting point from which to bend a bar. A "top' fuller " is shown in Fig. 235, A, a "bottom fuller" or "anvil fuller " at B, the latter resting by its shank over the anvil hole, the former being handled hammerlike, or by withes. The top fuller may be used while the bar rests upon the anvil face, or the bar may rest upon the bottom fuller and be struck by the hammer above, or the bar may be drawn down between the top and bottom fullers, the upper one being struck by the sledge while the bar is moved into successive positions until the iron is thinned or tapered by a series of grooves. The "nicking fullers " (Fig. 235) are made in various sweeps, and they fulfil the same purpose for circular shafts and rods that the others do for fiat bars.
To finish, plane surfaces, the "flatter " (Fig. 236) is employed. This is also struck by the sledge, and finishes or flattens the surface, removing the uneven ridges and indentations left by the hammers and fullering tools.
The "swages" form also a very large family in themselves. They are so termed because by their agency work is "swaged " or drawn down and made to assume definite outline corresponding with the shapes of the swages. These are, therefore, dies in principle, because the work can only assume the shapes given to the swages. Being also used in pairs, 'one top, one bottom, they are commonly called "top and bottom tools." Some shapes are given in Fig. 237. A are bottom swages, that is, they fit by their square shanks into the hole in the anvil face. The shape of the corresponding top swages is seen at B. The ordinary shapes are the half-round, the veed, and the hexagonal, each being required in different sizes. Fig. 238 represents a swage block for a heavier class of work, the various sectional forms around its edges answering the purpose of bottom swages. It is conveniently laid upon a cast iron stand, similarly to the anvil, on which stand it can also be laid flat in order that the central holes shall fulfil the functions of " heading tools," that is, of the type of Fie. 244, for finishing the square shoulders of bolt heads and similar flat expansions.
The top and bottom swages are frequently united in one with a bent rod of iron, which serves to keep them in line, and becomes a convenient handle. They are then turned "spring swages," or "spring tools" (Fig. 230).
There are three modes of handling tools employed by smiths. The first, just now referred to, of wedging the hammer head fast in the shaft. Tho second, that made use of with some of the sets, gouges, fullers, and flatters, in which the handle is simply thrust through an eye in the tool without any attempt at wedging, the reason being that their constant and almost close contact with red-hot iron would cause wedges to work slack almost directly. Hence the smith, previous to using either of these tools, usually strikes the butt end of the shaft on the anvil to tighten the head. Lastly there is the method of fixing by hazel rods. These are straight hazel sticks about 1/2-5/8 in. in diameter, twisted round the necks of the tools (Figs. 235, 237), the elastic wood preventing painful jarring and blistering of the hand of the smith. Before being bent, they are soaked in water and steamed over the fire, the operation being alternately repeated until they are sufficiently pliable to bear bending and twisting, but not taking more than a minute or two. The parallel rods are united permanently by a coupler, and are never taken off the tools except when they need renewal.
Very often it is the practice to substitute iron rods for those of wood, as being more durable, the rods being bent in the same manner. A hook wrench (Fig. 240) is used for giving a slight amount of torsion to flat bars while red hot, which have become twisted or winding in the process of forging. Fig. 241 may be taken as a type of the punches which are employed for piercing holes through red-hot iron, and Fig. 242 of the drifts for enlarging and making them parallel, the work being laid upon a bolster (Fig. 243) the while. Fig. 244 is a heading tool, of which there are several sizes used for shouldering the heads of bolts and rivets, or any work provided with collars, though where a collar is welded or otherwise formed on the centre of a bar, collar swages are often used in preference.
As a simple example of the practice of forging, take the connecting rod (Fig. 245), one with a forked end being purposely chosen as being more complete for purposes of illustration. This could obviously be made by building up - that is, the enlargements at the ends could be welded on a bar of the diameter A; or by swaging down, in which the diameter A would be hammered down from a bar of the sizes B or C of the larger ends; or by jumping up, where the ends would be beaten up or " upset" on a bar of diameter A. Or it can be made by a combination of these processes if a bar of medium dimensions only is available. Say we have a piece of bar of the dimensions A; we can get on very well with that. We build a fire in such a way as to obtain " a solid core of heat" - that is, we have a certain portion in front of, but away at a distance of a few inches from the tuyere, intensely hot, and for the time being open above, but flanked at back and front with two masses of wetted hard-caked small green coal or " slack," which partially confine the heat (Fig. 246), and form a reserve supply for the incandescent mass; and the larger the forging the larger the reserve of" stock." Putting that portion of the bar which requires to be heated - in this case the end - into the centre of the fire, cover it over with a mixture of stock and new coal, so as to enclose it completely, localising the heat where required by keeping wet coal over the portion which is not to be heated.