Part 10

Most smiths use the edge of the anvil for making scarfs. Place the edge of the metal, after it has been upset, on the edge of the anvil and strike down on the top with a hammer or sledge. This moves the metal with each blow and the end of the bar is increased, making, as it were, a series of steps. It is a process much the same as fullering except in place of the fuller you use the edge of the anvil. This is the quickest way to make a scarf, and the weld depends wholly upon how the scarfs are made in any one of the operations spoken of here.

If the scarf is well made it will be a little higher in the middle than at the sides, so that when the pieces are placed together the slag that forms will squeeze out. The welding is done as follows: Place the scarfs of both pieces separately in the fire, the scarfs downward. (When we speak of scarfs we refer to the bevelled edge of the roughest part of the scarf.) This prevents any impurities melting on the scarf surface. When the scarf begins to get hot enough to weld, iron sparks will blow out with the blaze. This is the sign to get things in readiness. One cannot linger for a moment when the iron is hot enough to weld. See that the anvil is clean. Have the hammer ready in hand. If one has a helper he will handle one piece while the smith handles the hammer and the other piece.

If there is no helper a hammer is placed conveniently near the anvil. The two pieces of iron are grasped by the smith, one in either hand, drawn out of the fire and given a sharp rap on the edge of the anvil or forge to remove any dirt or pieces of coal clinging to the scarfs. One piece is placed on the anvil and the other piece is put on top of this. The weight of the second piece holds the first piece in place until such time as the smith can get his hammer ready to strike. As soon as the pieces stick together the ends of the scarfs are welded first. They are the thinnest and will cool the quickest. The body of the piece welds while you are welding the scarfs. Both sides are worked upon, first on one and then on the other, till the piece is hammered down to the required size. In trial work it is best for one to use pieces of iron long enough to avoid the use of tongs.

_Butt welds:_ If the butt weld is carefully made it is perhaps the safest weld of all. This method is used mostly in welding round iron bars, 1-1/2 ins. in diameter up to 2-1/2 ins. They are made as follows: the ends of two bars are heated to a welding heat. Then they are brought out of the fire, put in a swage, end to end, and struck on the ends with a sledge hammer. While driving upon the ends the iron upsets when the contact takes place and at the same time the smith is driving the weld down. Two processes are acting here, one lengthwise and one downward. This makes the best weld, from the fact that the two ends that come together have a welding heat on the whole surface of each, a condition hard to get in any other kind of weld.

_Lap weld:_ Two flat pieces are laid face to face, as shown in picture, and are welded. One must be careful that the two pieces have the same temperature, otherwise the colder piece would cut into the hotter and make a defect.

_Cleft weld:_ If the weld is required to stand much strain, such as in parts of a locomotive frame, pieces are generally joined by the cleft weld. One piece is upset and split with a chisel. The two sides are spread apart. The other piece is scarfed on both edges to fit into this opening. If the pieces are very large much of the welding can be done while in the fire. The two pieces are placed together, in the proper position, in the fire. When the heat is hot enough to weld they are driven endwise. This drives the point of the one piece into the crotch of the other. Take them out of the fire and place upon an anvil or under a hammer. Small pieces are welded in the same way, except they may be driven with a hand hammer on the end just before driving upon the surface. The piece is reduced to the proper size and finished.

_Jump weld:_ When one piece of metal is to be welded at right angles to another piece, a jump weld is made. Many are made by using a bob punch, making a hollow depression in a flat piece, and a rounded or button head shape on the end of the upright. Heat the end of the upright and also the flat piece around the bob punch hole to a welding heat. Take them out of the fire and drive the button head down into the hole made by the bob punch.

Another jump weld can be made in the following way: when square iron is to be welded to square iron, one end is upset and flattened. The other end is simply upset a little when the upright is to be welded to it. These ends are brought to a welding heat, and the work is finished as in the first jump weld. The hammer plays an important part in these jump welds, for the scarf projecting at the base must be welded by the hand hammer.

WORK INVOLVING FLAT WELDS

_Making a corner plate:_ This corner plate shows two pieces of metal, 1/4 × 1 × 6 ins. welded in the corners, upset. The ends of the pieces to be joined are scarfed as explained in the flat weld. Both pieces are heated, then one placed on the other, driven down, and welded. They are shaped upon the edge of the anvil, and the ends are cut off to the length shown by the drawing.

_T weld:_ This is used in making a T plate. The cross piece is upset in the middle and scarfed by using the peen of the hammer as shown.

The upright piece is upset on the end and scarfed, same as was done on the corner weld. Both pieces prepared are then heated and welded as described in the making of the corner plate. The sketch given here shows fairly well the different steps.

XXIII

MILD STEEL OR SOFT STEEL

Mild steel, or soft steel, is supplanting wrought iron in many shops. Any smith who has worked with this metal will always prefer it to wrought iron. It is much stronger and can be bent, forged, and twisted in all manner of shapes, without cracking or splitting. This cannot be said of wrought iron. Therefore, when mild steel is used one is sure of finishing his problem, provided he understands the process of heating it. The matter of heating mild steel is the vital thing. It should never be worked at a welding heat or below a red heat. If worked either above or below this point it will show it by splitting or cracking before the problem is finished. Large crystals formed by working at or above the welding heat will cause the breaks, and internal fractures when working at the low heat will cause the cracks. However, this can be worked at a black red heat if the blows delivered affect only the surface and do not penetrate to the centre. This metal lends itself to forging better than wrought iron does. It is very good for most kinds of forging and particularly good for making weldless rings. One of the best problems to illustrate one of the many uses to which soft steel may be put is the making of a weldless ring.

A piece of soft steel 1 in. wide, 1/4 in. thick, 4 ins. long, is the stock used for this ring. With a centre-punch mark off 3/4 in. from each end. (See sketch.) In each centre-punch mark punch a 1/4-in. hole through the piece. With a hot chisel cut between these holes half way through on one side. Turn it upside down and finish cutting through from the other side. Now drive the chisel through, widening the slot out. Trim up the inside of the slot. Cut away all rough edges. Upset the piece on the anvil after heating and drive down on the ends. This will increase the size of the hole by shortening the length and bulging the sides out. The piece is now put on the horn of the anvil and rounded into a ring. The ends are now trimmed off or driven down into the thickness, as shown in the drawing. This is the method of making a weldless ring. It is easily made out of soft steel. It would require a very fine grade of wrought iron to do a piece of work of this kind, for wrought iron is fibrous and unless great care is exercised in forging it will split at the ends along the grain when opening it after the slot is cut in.

Steel is much cheaper than wrought iron, another good reason for its use. For the making of nuts, too, it is better than wrought iron. All one needs to do is to cut a piece off the end of a square bar, the proper thickness, punch a hole in it, and square it up. If wrought iron were used, to get the same strength one would need to bend the iron around a mandrel in the shape of a ring so that the grain of the iron would run around the hole of the nut. Then it should be welded and shaped into a square nut.

CHAIN HOOK OF SOFT STEEL

Up to the present time our work has been with wrought iron entirely. This hook is to be made out of soft Bessemer steel, which of course is very different from high carbon steel. It is the cheapest of the steels. All building material, railroad rails, boiler plates, steel cars, etc., are made of this cheap soft metal. The process of manufacture is quite simple. Molten cast iron, taken from the cupola, or blast furnace, is poured directly into a so-called Bessemer converter--a pear shaped vessel. Air is blown through the mass of molten metal. The air adds oxygen to the bath, and increases the heat to a temperature high enough to burn out all the impurities from the cast iron. This converts it into steel. It requires no more than nine or ten minutes to convert fifteen tons of cast iron into soft steel. The air is shut off and a sufficient amount of ferro-manganese is added so as to give the proper amount of carbon. The liquid steel is poured into ingots and these ingots while still hot are rolled into the shape used for the market. A piece of this kind of steel you are going to use to make a hook. Soft steel can be worked in the same way as you work wrought iron. It is not fibrous like wrought iron and is not apt to split unless worked at a low temperature.

_Stock:_ Soft steel, 5-1/4 ins. long, 3/4 × 1/2 in.

_Directions:_ The drawing gives all the steps necessary for the making of this hook. Notice in the drawing when the stock is given it is fullered down 1-1/8 ins. from one end. This is the amount needed to make the eye. After fullering the stock it is placed on the anvil and squared up.

These square corners are knocked down, making it round. When the body of the hook itself is drawn out, like the drawing, a hole is punched through the eye, using the same kind of punch as you did to make the nut. While using the punch keep cooling it off in cold water to prevent its getting hot; if you do not, the end is apt to burr and rivet itself into the iron. It also prevents its sticking into the hole. Place the ring of the eye on the point of the anvil and round up carefully with light blows from the hammer.

When rounded up drive the punch in again to the required size. This finishes the eye. The body of the piece is now gone over carefully with calipers and square to get the diameters and length. Bend the small point at right angles to the axis of the hook, like the drawing. Now it is ready for bending in the middle. Heat the middle very hot. Cool off the point about 1/2 in. Place the middle on the horn of the anvil and strike upon the small turned up cold nib to bend the hook from this point. By striking upon the cold end to bend it one can do so without destroying the shape. It will stand a lot of work upon it when cold.

When the hook is bent around as nearly like the drawing as you can, flatten it out at its widest part by laying it upon the anvil and striking with the hammer. The cross section of the drawing shows the shape that this flattened part should be.

This is what we call a solid eye hook. Another way of making an eye is to take round material of sufficient length to bend an eye on the end by placing the piece over the horn of the anvil. The body of the second hook can be made out of round iron, pointed down at the end and finished up the same as the first.

_Bending a corner in iron and upsetting while bending:_ In this problem we bring in the making and bending of iron, so that the thickness at the corner must be sharp on the top side and rounding on the inside--without flaws or cold-shut. This bending method applies to all metals, whether of square iron or wide flat iron.

_Stock:_ Piece 6-1/2 × 3/8 in. square.

_Directions:_ Heat the metal in the middle and bend it over the rounding edge of the anvil.

When the piece is bent we still have to make it square on the outside and rounding on the inside. The bend just made should be placed in the fire and re-heated. Cool the stems off in the water to within one inch of the bend. Place the point of the cold stem on the anvil and strike on the hot corner. This is repeated on both outside corners until the piece assumes the shape of the drawing. This same result can be obtained by upsetting the metal in the centre before bending, as shown in the drawing.

FLAT WRENCHES

Wrenches are used for screwing nuts on bolts. They can be made in two ways: (1) One known as the solid wrench is made without welding, (2) the other, is made of wrought iron and is welded.

_S wrench of soft steel:_ The sketch here is of a wrench made from soft steel 1/2 × 1 × 5 ins. Fuller down the stock edgewise as shown. Draw out the centre 1/4 in. thick and taper it from 3/4 to 5/8 × 5 ins. long. Cut the corner off, as shown by the dotted lines, and round the two ends up to the size given. Punch a 1/2-in. hole in the large end and a 3/8-in. hole in the small end of the bar. With a sharp chisel cut a V-shaped plug out of each end, tangent to the circles.

_Jaws:_ The jaws of the wrench are finished with a tool called a wrench hardie, placed usually on the anvil for the purpose of finishing up work of this kind. Finish up both ends in the same way. Heat the wrench at the nick and cool the jaws off in water. Place the nick on the horn of the anvil and bend it as shown. Repeat on the other end. If the wrench is carefully made it will require no filing to fit the nut. These wrenches are sometimes polished and case hardened to prevent the jaws from wearing while in use.

_Large flat wrench:_ A quick way to make a large wrench is to make it of wrought iron. A piece of iron 1 × 1/2 × 4 ins. is bent at almost a right angle. The inside corner is the corner made by the natural bend the metal takes when shaping it.

Scarf this corner by placing the peen of the hammer on the corner and striking the face of the hammer with the sledge or by using a bob punch if one is available, or it may be made by using the peen of the hammer without the use of a helper. Select a piece of round iron 7/8 in. in diameter. Upset the end of this and scarf it to fit the scarf made in the angle piece. Heat both pieces to a welding heat. Place them on the anvil and weld the handles to the jaws. The inside is rounded up at the same time the scarfs are being welded into place. Draw the points out to a short taper and bend them up in the shape of a wrench on the heel of the anvil. This is a simple way of making a large wrench that can be used for all kinds of work.

_Alligator wrench:_ Stock 1 × 1/2 × 5 ins. steel. The alligator wrench is one of the handiest tools to have in a home or shop. For general repair work it is indispensable and is easily made. Mark off 1-1/2 ins. from the end of the stock. This is the jaw part. Place the other end of the stock in the fire. Take it out and from the centre-punch mark draw the handle out 3/4 in. wide, 3/8 × 8 ins. long, and tapering to 3/8 × 1/4 in. at the extreme end. The edges of the handle should be rounding. Place the jaw ends in the fire and heat red hot. Punch 1/4 in. hole back 1-1/2 in. from the end. Draw out the end and shape as shown in the drawing. With a three-cornered file, file the teeth on a slant and close together. This slanting will allow the wrench to let go of the work better than those filed at right angles to the axis of the piece. The teeth should slant backward and should be put only on one side of the jaw. Both jaws should be hardened and tempered a blue colour. To do this, heat the body of the steel back of the jaw to a red heat and plunge the whole into water one inch beyond the depth of the jaw. When cold take it out and polish. Draw the temper in the same way as you would for a knife blade. (See article on tempering and hardening.)

SOCKET WRENCHES

Socket wrenches are useful for tightening nuts in places that are difficult to reach. It is most convenient when many nuts of the same size are used, as bolting shaft irons for vehicles, etc. Some are made to fit an auger brace; some have solid handles with a cross bar, and some have holes punched in the shanks to place the iron bars in while twisting the nut on the bolt. This drawing shows a style of wrench in general use. It can be made in two different ways. One is called the welding method, the other is the solid method.

_Welding method:_ Cut a piece of metal 1/4 × 1 in. of Norway iron. The length of this bar must be determined by the size of the nut it is to be used for. Heat one end of the piece of iron and scarf it. Repeat on the other end. Bend the piece into a collar or ring, weld the two ends together, forming a cylinder about 1 in. deep--any diameter. Select a piece of round iron for the shank, the size depending upon the size of the socket. Upset one end of the round iron to fit the collar made.

Drive the shank into the collar about one half the depth of the collar, place it in the fire, and at a welding heat weld the collar to the shank. If the wrench is to be for a hexagonal nut, make a hexagonal drift pin (a square one for a square nut), and drive the pin into the collar. Place it all on a swage and round up with a top swage. Drive the collar down until it takes the shape of the drift pin. To do this successfully requires many heatings, and it can be done only while the metal is hot enough to yield always under the hammer blows. Should the drift pin stick after the collar is driven into it, place the pin on the anvil, giving it a slanting blow. This will loosen the pin and it will come out easily.

The shank should now be driven down as shown in the sketch, and two holes punched in at right angles to each other. These are holes to place iron bars for turning the wrench. These holes can be made in two ways: one, by forming lugs or bosses on the shank and punching holes in each one, or, a sharp tapered round punch, flat and sharp on the end, can be used to split the metal and force the sides out as the punch is driven in.

If the cross bar is to be used in place of the holes, a cleft scarf made in one end of the shank and a 3/8-in. bar of iron welded to this about 4 or 6 inches long on either side of the shank will act as a handle.

_Open-sleeve or socket wrench:_ The wrench given here is for practically the same use as the one just described. It is lighter than the other. The opening is longer and allows the bolt to protrude through the nut without forcing the wrench off. This wrench is made of machine steel, and the size must be determined by the size of the nut.

For a small wrench take a bar of 3/8 × 1-1/4 × 6 in. soft steel. Mark off on the bar 2 ins. from each end and on these centre-punch marks fuller down on the top and the two sides so that the bottom of the fuller will measure 1/2 × 1/4 in. Draw these ends out to 1/2 × 1/4 in. any length. Cut the four corners off and make the centre round. Bend the two arms as shown and punch 1/2 in. hole through the boss. Be careful to prevent cold-shuts while doing this. Drive a drift pin into the hole and forge the shape as shown. Bend the two arms as shown and weld together. These should be worked down to a 1/2-in. round. The ends can be made into a brace shank by squaring the end and tapering it to fit the jaws of the brace. Or weld a piece of 1/2-in. round iron long enough to bend it into the shape of a brace, putting a round knob on the end for a hand hold. This makes a simple wrench and one that can be used in many places where flat wrenches are not convenient.

OPEN WIRE ROPE SOCKET

These sockets are made for wire cables, ropes, etc., and are best made of mild steel. Place the end of a 1-1/2-in. square bar in the fire and reduce it as shown in the sketch. Cut two outside corners off, as shown by the dotted lines. Round the ends up. Punch a 1/2-in. hole 2 ins. from the rounded end in the centre of the piece. Then cut a piece out with a sharp chisel, equal to the width of the hole. With the fuller, open the jaws out. Now cut the socket off 4 ins. from the rounded end and drill a 1/2-in. hole through this end of the socket. A drift pin 3/4 in. on one end and tapered to 3/8 in. on the other is now driven into the 1/2-in. hole at the jaw side.

Forge the shank as shown in the drawing while the drift pin is in. While forging keep driving the drift pin into the hole. When finished the hole should measure 3/4 in. at the large end and 1/2 in. at the small end. When the socket is finished cut the ends square and smooth up. During all the time the steel should never be worked below a red heat and most of the time at a high heat, below welding heat, until it is ready for finishing. Now the jaws are ready to be closed. This is done by placing a piece of flat iron, 3/4 in. thick and the width of the jaw, in between the opening, and close the jaws on this either with the hand hammer or a flatter. Drill a 1/2-in. hole in the middle of the end. This is made for the pin. Make a pin to fit this hole out of 1/2-in. round stock. Upset the end of the bar a little and place it in a heading tool, driving down and forming a head 1/8 in. thick and 3/4 in. in diameter. Take it out of the heading tool, cut the bolt off 1/2 in. longer than the width of the jaws. This allows for a 3/16-in. hole and pin. A small 3/16-in. hole is now drilled in the shank of the bolt and a split pin is put into the hole to prevent its falling out. The split pin is made by flattening down a piece of 1/8-in. wire in a small swage to a half round. Now double over to form an eye on one end of the two flat planes coming together. When this is put in through the hole, a chisel put in the opening will widen out the ends, thus preventing them from falling out.

HINGE AND BUTT

The hinge and butt are used on doors and gates. This fastening is made similar to the other hinges, except the eye is welded, instead of being a solid eye.

_Stock:_ 1/4 × 1 × 7-1/2 ins. wrought iron.