Fig. 4.—Fire Tools.
A, poker; B, rake; C, shovel; D, dipper; E, sprinkler.
3. Fuels.—The fuels used for blacksmithing are coal, coke, and charcoal. Most commonly a bituminous coal of superior quality is used. It should be free from sulphur and phosphorus, because the metals will absorb a certain amount of these impurities if they are in the fuel. The best grade of bituminous coal has a very glossy appearance when broken.
Coke is used mostly in furnaces or when heavy pieces of metal are to be heated. It is a solid fuel made by subjecting bituminous coal to heat in an oven until the gases are all driven out.
Charcoal is the best fuel, because it is almost free from impurities. The most satisfactory charcoal for forging purposes is made from maple or other hard woods. It is a very desirable fuel for heating carbon steel, because it has a tendency to impart carbon instead of withdrawing it as the other fuels do to a small extent. It is the most expensive fuel, and on that account, and because the heating progresses much more slowly, it is not used so generally as it should be for heating carbon steel.
4. The Anvil.—The anvil ([Fig. 5]) is indispensable to the smith, for upon it the various shapes and forms of metal can be forged or bent by the skilled workman. Except for a few that have been designed for special purposes, it has a peculiar shape which has remained unchanged for hundreds of years. That the ancient smiths should have designed one to meet all requirements is interesting to note, especially as most other tools have undergone extensive improvements.
Anvils are made of wrought iron or a special quality of cast iron. In the latter case the face is sometimes chilled to harden it, or is made of steel which is secured to the base when the anvil is cast. Those that are made of wrought iron are composed of three pieces: the first is the base B which is forged to the required dimensions; the second is the top which includes the horn C and the heel; the third is the face A of tool steel which is welded to the top at the place shown by the upper broken line. The top and base are then welded together at the lower broken line.
Fig. 5.—The Anvil.
After the anvil has been finished, the face is hardened with a constant flow of water, then it is ground true and smooth and perfectly straight lengthwise, but slightly convex crosswise, and both edges for about four inches toward the horn are ground to a quarter round, thus providing a convenient place for bending right angles. This round edge prevents galling, which is liable to occur in material bent over a perfectly square corner.