Several kinds of hammers are used in a forge shop. The commonest shape is the ball peen shown at A, Fig. 8. Other kinds are the straight peen and cross peen illustrated at B and C. A square-faced hammer, sometimes called a blacksmith's hammer, shown at D, is occasionally used on tool work. Commonly a ball peen hammer of about 1 1/2 pounds weight is used.
In the fitting of the handle to the head great care should be taken. Hammer handles are made elliptical in cross-section. The major axis of this ellipse should exactly coincide with that of the eye of the head. The reason is that the hand naturally grasps the handle so that its major axis lies in the direction of the line of motion.
Hence, unless the handle is properly fitted in this particular, there will be constant danger of striking a glancing blow. The handle should also stand at right angles to a center line drawn from the ball of the peen to the face. The eye in the head is usually so set that the weight on the face side is greater than that on the peen. The effect of this is to so balance the tool that heavier and more accurate blows can be struck than if the weight were evenly balanced on each side of the eye.
Fig. 8. Common Types of Hammers.
Sledges are heavier hammers used by the blacksmith's helper and vary in weight from 5 to 20 pounds. The three common shapes are shown in Fig. 9; A, B, and C, being cross-peen, straight-peen, and double-faced sledges, respectively. A sledge for common work ordinarily weighs about 12 pounds. Sledge handles are generally about 30 to 36 inches long, depending on the nature of the work to be done.
Fig. 9. Common Types of Sledges.
Next to the hammer in importance is the anvil. This may be any block of metal upon which the piece to be shaped is laid.
The anvil must be of such a weight that it can absorb the blows that are struck upon it without experiencing any perceptible motion in itself. The ordinary anvil, Fig. 10, has remained unchanged in form for many hundreds of years. Anvils are sometimes made of special shapes, but the one here shown is the common one. An anvil of this form serves for the execution of any work that may be desired. As now made, the body a is of wrought iron to which a face of hardened steel is welded. From one end there projects the horn 6, and the overhang of the body at the other end c is called the tail. At the bottom there are four projections d, called the feet, which serve to increase the base upon which the anvil rests as well as to afford the means for clamping it down into position. In the tail there is a square hole and a circular hole. The former is called the hardie hole, the latter the spud hole.
Anvils are also made with a body of cast iron, to which a face of steel is welded.
The anvil should be placed upon the end of a heavy block of wood sunk into the ground to a depth of at least 2 feet, so that it may rest upon a firm but elastic foundation. As the anvil is subjected to constant vibrations, by the nature of the work, it is necessary that it should be firmly fastened to the block.
Anvils are classed and sold by weight. The weight is generally stamped on the side of the anvil. Three numbers are used. The first to the left shows the weight in English hundredweight of 112 pounds each. The middle number shows the additional quarters of hundredweight and the right-hand figure the number of odd pounds. For instance, an anvil marked 2-3-4 would weigh 2X112+3/4 of 112+4 pounds=312 pounds and would be known as about a 300-pound anvil.
Next to the hammer and anvil in importance and usage are the tongs. They vary in size from those suitable for holding the smallest wires to those capable of handling ingots and bars of many tons in weight. The jaws are also adapted to fit over the piece to be handled and are of a great variety of shapes. As the requirements of each piece of work vary so much from those which precede and follow it, it is customary for the blacksmith to dress his own tongs and adapt them, from time to time, to the work he has in hand. Comparatively few, therefore, of the various shapes of tongs found in shops are manufactured and for sale. A few of the general types and forms in common use are here given.
A, Fig. 11, shows a pair of flat-jawed tongs, the commonest shape used. B is a pair of pick-up tongs used for holding work while tempering, and picking up pieces of hot metal. C is a common shape used for holding both square and round iron, the jaws being bent to fit the stock in each case. A modification of this shape is also used for heavy steam-hammer work. Tongs frequently have the jaws made in some special shape for a particular piece of work, the object always being to have the jaws grip the work as firmly as possible.
Tongs must be always carefully fitted to the work. Tongs which take hold of the work as shown at A and B, Fig. 12, should not be used. The first pair shown have the jaws too close together, the second, too far apart. When properly fitted the jaws should touch the work throughout the entire length as shown in the lower sketch C. To fit tongs the jaws are heated red hot, the piece to be held placed between them, and the jaws hammered down until touching their entire length. Tongs which do not fit the work perfectly should never, under any circumstances, be used. When in use on all but the smallest work, a link is driven over the handles to grip the tongs in position, as shown.
Fig. 11. Types of Tongs.
Fig. 12. Fitting Tongs for Work.
These tools are used for smoothing off flat work when finishing. The set hammer, Fig. 13, is used for working up into corners and narrow places. The flatter, Fig. 14, is used on wide flat surfaces. The face of the set hammer used on light work is generally about 1 1/4 inches square. That of the flatter about 2 1/2 inches square, although the sizes vary, depending upon the kind of work. Swages. Swages, shown in Fig. 15, are used for finishing round and convex surfaces. The upper tool is known as the top swage and is provided with a handle. The lower one is the bottom swage and is held in place by a square stem or shank which extends downward and fits into the hardie hole of the anvil. Tools of this character should never be used on an anvil where they fit so tight that it is necessary to drive them into place. The swages shown here are used for round work. Swages are also made for octagonal, hexagonal, and other shapes.
Fig. 13. Set Hammer.
Fig. 14. Flatter.
Fig. 15. Swages for Round Work.
Fig. 16. Fullers.
Fullers, which are used for working grooves or hollows into shape, are also made top and bottom as shown in Fig. 16. The top fuller is for finishing into round corners, around bosses, and on the inside of angles as illustrated later on. The fuller is also used to spread metal when it is wished to work the metal only in one direction. The metal spreads at right angles to the working edge of the fuller.
Swage blocks, a common sort of which is shown in Fig. 17, are used for a variety of purposes, mostly for taking the place of bottom swages. These blocks are commonly made from cast iron and weigh about 150 pounds.
The tools used commonly are calipers, a carpenter's 2-foot steel square, dividers, rule, shovel, tongs, ladle, poker, and a straight bar for loosening the fire. In addition to the ordinary calipcrs, a blacksmith usually has a pair of double calipers similar to those shown in Fig. 18. With these, two dimensions may be used, one side being set for the thickness, and the other for the width, of the material.
When several measurements are to be made particularly on large work, a strip of light stock about J inch by 1 inch wide is used. The different dimensions are laid off on this with chalk or soapstone. In use the strip is held against the work and used in the same manner as a rule. A light rod having a small bent end, made by bending over about \ inch of stock at right angles, is also sometimes used, particularly when working under the steam hammer. The dimensions may be laid off from the inside of the hooked end. When in use the hooked end is pulled against the end of the material. Soapstone crayon is ordinarily used for marking on iron. The marks do not burn off, but will not show at a red heat. Marks to show at a high heat must be made by nicking the corner of the bar with a chisel or by marking with the center punch. Another common way of making measurements on hot material is to lay off the different distances on the side of the anvil with chalk, the dimensions being laid off from one comer or end.
Fig. 18. Double Calipers.