Fundamental Forging Operations

Forging may he defined as changing the shape of a piece of metal by heating and hammering. All the various operations that a. blacksmith performs in forging iron may be classified into a surprisingly small number of fundamental or basic processes. Once these are mastered, the beginner is well on his way to success, and he can do practically any ordinary piece of forge work. These fundamental operations are (1) bending and straightening; (2) drawing, or making a piece longer and thinner; (3) upsetting, the opposite of drawing, or making a piece shorter and thicker; (4) twisting; and (5) punching. Other operations commonly done by a blacksmith, but which are not strictly forging, are welding, tempering, drilling, threading, filing, etc.

290. Bending and Straightening.—In bending at the anvil, two things are most important:

-1. Heat the iron to a good bright-red heat, almost hut not quite white hot, throughout the section to be bent.

2. Use bending or leverage blows—not mashing blows.

The iron should be so placed on the anvil and so struck that it can bend down under the hammer blow without being forced against the anvil find mashed. If the iron is struck at a place where it is resting firmly on the anvil, it will be mashed instead of bent. A few moderately sharp blows are better than several lighter blows.

Abrupt square bends can be made over the face of the anvil near the chipping block where the corner of the anvil is rounded to prevent marring or galling the iron.

Care should be taken to keep the iron at the proper bending heat. If it gets below a red heat, it should be put back in the fire a.nd heated again. To bend a piece at a certain point, without bending the adjacent section, the piece may be heated to a high red heat and then quickly cooled up to the point of bending by dipping in water. Bending is then done quickly by hammering, or other suitable methods.

Bending may be accomplished in several ways besides hammering over the anvil. The iron may be heated and then put in the pritchel or hardy hole and bent by pulling; or it may be clamped in a vise and bent.

Straightening can usually best be done on the face of the anvil. The stock should always be firmly held and then struck with the hammer at

points where it does not touch the face. Sighting is the best way to test for straightncss and to locate the high points that need striking.

Fig. 252.—To make a uniform bend in the end of a rod. strike the part that projects beyond the horn and keep feeding the rod forward with the tongs as the bonding progrcitfCfl. Keep the iron at a good working heat and do not strike the rod where it rests on the horn.

Bending Flat Bars Edgeways.—A flat bar can usually be easily bent edgeways by heating and placing over the horn and bending the two ends

Fig. 253.—Flat iron may be bent edgewise by heating to nearly a white heat and bending «slowly with ton»*. This method is good in making flat chain hooka.

Bending of heavy pieces can sometimes be b68t accomplished in the hardy hole-

Bending of heavy pieces can sometimes be b68t accomplished in the hardy hole-

down slowly, using the hands if the piece is long enough, or two pairs of tongs in the case of short pieces (see Fig. 253). Sometimes the bending can be done easily by putting one end of the piece in the hardy hole and pulling on the other end (see Fig. 254). If the stock starts to buckle, it should be laid flat on the anvil and straightened. Hammering the outside edge of the iron when laid flat will tend to stretch it and therefore help with the bending. Once the bend is well started, hammering the piece on edge around the horn is not so difficult. The stock should always be firmly held, either by hands or with tongs, and the parts to be bent should be at a high red heat. Places not to be bent should be comparatively cold.

291. Bending and Forming an Eye.—One of the most common bending jobs in the blacksmith shop is that of forming an eye on the end of a rod. The following is a good method of making such an eye:

1. Heat the rod to a good red heat back for a distance of about 5 to 8 in., depending on the size of the eye.

2. Quickly place the rod across the face of the anvil with just enough of the heated end projecting beyond the edge of the anvil to form the eye. For exact work the length of hot iron that is to project over may be quickly measured with a metal rule. The iron should be placed across the anvil well up near the horn where the edge is rounded.

3. Bend the end down, forming a square bend, with a few well-directed blows. Work rapidly before the iron cools.

4. Heat the end of the stock and start bending the tip end around the horn. Work from the tip back toward the stem. Keep the iron hot throughout the part being bent; otherwise the bending will be slow and difficult, and the iron will not bend at just the places desired. If the square bend at the juncture of the stem and eye tends to straighten out, it is an indication that the end of the stock is not being kept hot enough while being bent.

5. Round the eye by driving it back over the point, of the horn, noting carefully where it does not rest against the horn and striking down lightly in these places. Keep the iron well heated.

6. Center the eye on the stem, if necessary, by placing the stem flat on the anvil face with the eye projecting over the edge, and striking the eye. The stock should be well heated at the juncture of the stem and eye, but the eye itself should be practically cold. Such a condition can be produced by heating the whole eye and then quickly cooling most of the rounded part by dipping in water.

292. Drawing.—Drawing is the process of making a piece longer and thinner. Two important points should be kept in mind while drawing:

1. The iron must be kept at a good forging heat, a high red or nearly white.

2. Heovy, straighl-doum, square blows should be struck.

Many beginners make the mistake of striking a combination down-and-forward pushing blow, thinking that the pushing helps to stretch the metal.

A. Placo ft well-heated iron across the anvil with enough stock projecting over to form the eye. Where the eye must be made accurately to siie, use a metal rule or square for measuring. Work rapidly.

B. Bend tho projecting portion down, forming a right angle.

C. Finish the right angle bend by striking alternately on top and on the side, keeping the iron at a good working heat all tho while.

D. Start bonding the tip end around the horn, being careful to strike "overhanging" or bending blows.

Pro. 255a. Step« in making an eye {continued).

E. Gradually work bask from the end to the square bond.

F. Turn the eye over and ciloae it up. Exert considerable back pull on the tongs to keep the upper part of the. eye up off the horn. In this position the hammer can strike bending blow» instead of flattening or mashing blows.

G. Round the eye by driving it back over the point of the horn- Carefully note where the eye does not touch the horn, and strike down lightly in these places.

II. To straighten the atem of an eye, place it aero** the corner of the anvil face *nd strike the high points while the iron is at ft good working heat.

Drawing can be done more rapidly over the horn than on the face of the anvil, a* the round horn wedges up into the metal and lengthens it, and there is less tendency for it to stretch in all directions. If a piece tends to get too wide it may be placed on edge and hammered.

Hammering after the red heat leaves Is hard work and accomplishes little. Also, the iron is apt to split or crack if hammered too cold.

Drawing Round Rods.—To make a round rod smaller, the following steps should be carefully followed.

1. Make it four-sided, or square in cross section.

2. Draw it to approximately the desired size while it is square.

3. Make it dutinclly eight-sided by hammering on the corners after it is drawn sufficiently.

4. Make it round again by rolling it slowly on the anvil and hammering roundly with light blows or taps.

An attempt to draw round rods without first going to the square section not only requires a lot of extra work but usually results in a badly distorted and misshaped piece.

Pointing a Rod.—If a round point is desired on a rod, a square tapered point should first be made. It is then easy to make it eight-sided and finally round.

In making a point the rod should not be held flat on the anvil, but the back end should be raised somewhat. Also, the hammering should be

Fio. 256.—In pointing a rod or bar, raise tho back end, tilt (he toe of the hammer down, and work on the far edof the anvil. Round points should be mode »quarc first, then eight-aided, and finally round.

done with the toe of the hammer lower than the heel, so that the desired angle for the point is formed between the hammer face and the anvil. The hammering should be done on the far edge of the anvil, so that the toe of the hammer will not leave marks in the anvil face.

Fig. 257.—Roiling a punch or pointed round rod on a flat surface and watching the point will tell whether it is straight and the point is centered. If the point wobbles, it is off center.

293. Upsetting.—Upsetting is simply the reverse of drawing, or the process of making a piece shorter and thicker. It is done when more metal is needed to give extra strength, as when a hole is to be punched for an eye. There are two main points to be observed in upsetting:

1. Heat the bar or rod to a high red or nearly white heat throughout the section to be upset.

2. Strike extremely heavy well-directed blowa

Light blows simply flatten and burr the end instead of upsetting the piece throughout the heated section. The extra-heavy blows needed for upsetting can best be struck by first striking a light blow or two to get the direction of striking and then following with an extra-hard blow.

Fig. 258.—To insure success in upsetting, work the iron just under a white heat and strike tremendously heavy blows. Light blows simply flare the end without upsetting very far back from the end.

Probably the best way to upset a short piece Is to place the hot end down on the anvil and strike the cold end. The hot end, of course, may be up, but it is usually easier to upset without bendiug if the hot end is

Fig. 258.—To insure success in upsetting, work the iron just under a white heat and strike tremendously heavy blows. Light blows simply flare the end without upsetting very far back from the end.

down. If the bar starts to bend it should be straightened at once. Further hammering will simply bend it more instead of upsetting it.

In order to heat thoroughly the part to be upset, and yet confine the heat to this part, it is sometimes better to heat the work somewhat further than the upsetting is to go and then cool it quickly back to the line of upsetting by dipping in the water.

The end of a long bar may be upset by laying it on the anvil face with the hot end projecting beyond the edge, and striking heavy blows endways with the hammer. If the bar is long and heavy enough, it

Fig. 259.—When it ¡9 desired to heat only a small portion of an iron, as in upsetting only the end of a piece, it is sometimes necessary to heat a larger portion, and then cool back to the desired point by dipping in water.

may be upset easily by ramming the hot end against the face or the side of the anvil.

294. Twisting.—Twisting is really a form of bending. Small pieces may be twisted by heating the section to be twisted to a uniform red heat, clamping a pair of tongs at each end of the section and applying a turning or twisting force. If the piece is too large to be twisted this way (say more than about Y\ in. thick by 1 in. wide), it may be clamped in a vise and twisted with a pair of tongs or a monkey wrench, the jaws of the vise and the wrench being carefully placed at the ends of the section to be twisted. It is important that the work be done rapidly before the iron cools too much. For a uniform twist, the iron must be at a uniform temperature.

If the twist must be confined to a very definite section of the stock, it is a good plan to place center-punch marks at the ends of the section before the iron is heated.

Care must be exercised in twisting so as not to get the piece out of alignment. If it becomes necessary to straighten the bar after twisting,

Fig. 259.—When it ¡9 desired to heat only a small portion of an iron, as in upsetting only the end of a piece, it is sometimes necessary to heat a larger portion, and then cool back to the desired point by dipping in water.

it may be done by striking with a wooden mallet, rather than a hammer, in order to prevent marring the sharp corners of the twisted part.

Fig. 260.—Heavy bars may bo twisted by heating to a good working heat, clamping in a vise, and twisting with a wrench or pair of tongs.

295. Punching Holes.—It is sometimes easier to punch a hole in a picce of'iron than to drill it; and for some purposes a punched hole is better. For instance, in forming an eye on the end of a bar in making a hook or a clevis, punching makes a stronger eye. A small or medium-size hole is first punched and then expanded by driving the tapered punch on further through the hole, first from one side and then the other. Thus less material is wasted than if the hole were drilled, and a stronger eye results.

The steps in punching a hole in hot iron are as follows:

1. Heat the iron to a good working temperature, a hi^h red or nearly white heat.

2. Place the hot iron quickly on the flat, face of the anvil—not over the prtidul hole or hardy hole. Punching over a hole would stretch and bulge the iron.

3. Carefully plare the punch where the hole is to be and drive it straight down into the metul with heavy blows until it is about two-thirds of the way through.

4. Turn the iron over and drive the punch back through from the other side. Reheat the iron and cool the punch if needed. The punch should be carefully located so as to line up with the hole punched on the other side.

5. Just as the punch is about to go through, move the piece over the pritchel hole or hardy hole to allow the small pellet or slug to be punched out.

6. Enlarge the hole to the desired size by driving the punch through the hole first from one side and then the other. Always keep the metal at a good working temperature, reheating as may be necessary.

May Metal Vise

Fig. 260.—Heavy bars may bo twisted by heating to a good working heat, clamping in a vise, and twisting with a wrench or pair of tongs.

B. Then turn the iron over and drive it back through from the other aide.

C. Finally move the piece over the pritchel hole or hardy hole, to allow the slug or pellet to be driven through.

B. Then turn the iron over and drive it back through from the other aide.

C. Finally move the piece over the pritchel hole or hardy hole, to allow the slug or pellet to be driven through.

The end of the punch should be dipped in water frequently to keep it from getting too hot. A little powdered dry coal dropped into the hole will help to keep the punch from sticking.

Fig. 262.—In punching hot iron, the punch should be cooled frequently by dipping into water.

Most beginners have difficulty in placing the punch so as to get the hole centered in a bar. If, in placing the punch, it is found to be off center, it may be leaned and twisted slightly until it is in the correct position.-

In punching hot iron, it is mueh better to use a punch with a handle in it, as it is uncomfortable to hold a short punch on a red-hot bar.

296. Forming Punched Eyes.—Usually, although not always, when a hole is to be punched for an eye, as in a chain hook or a clevis, it is best to upset the stock first so as to give more metal and make a stronger eye.

After upsetting, the end is shaped and the corners are rounded before punching. This can best be done by forming a neck or shoulder just back of the eye by hammering over the far edge of the anvil, as shown in Fig. 263.4. The end is then further shaped and the corners rounded by working over the anvil as suggested in the various other views of Fig. 263. Having the end thus shaped, the hole may be punched in the usual fashion.

In a clevis, the holes are punched with straight sides to fit the clevis pin. For holes in chain hooks, however, it is desirable to have the edges and corners rounded. This can be done by placing the eye at an angle on the end of the horn and making the stock approximately eight-sided and then finally round by rolling slowly while striking light, rapid blows (see Fig. 264).

Fig. 262.—In punching hot iron, the punch should be cooled frequently by dipping into water.

Fig. 263.—Forming a shoulder or neck, preparatory to punching a hole for an eye. The iron is first driven down against a comer of the anvil, as shown at A. The end of the piece is then shaped and rounded by working over the corners and the horn of the anvil, as suggested in the various other views.

Fig. 263.—Forming a shoulder or neck, preparatory to punching a hole for an eye. The iron is first driven down against a comer of the anvil, as shown at A. The end of the piece is then shaped and rounded by working over the corners and the horn of the anvil, as suggested in the various other views.

eye is placed on the horn at an angle and the stock made approximately eight-sided. It is then rounded by rolling it slowly on the horn and striking fast light blows.

297- Cutting with the Hardy.—The blacksmith does most of his cutting of iron and »tool on the hardy rather than with a hack saw. Although the hardy does not leave quite so smooth a cut as a saw, it Is , quite satisfactory' for most work. It cuts faster and easier than a saw

through from one «id*, being carfeful to strike overhanging blows at the la*t to prevent the hammer from striking the cutting edge.

To use a hardy, the rod or bar to be cut is simply placed on it and hammered down against the sharp edge. Hardies may be used for either hot or cold cutting. Some smiths prefer to keep two hardies, one that is thick and stocky and tempered for cutting cold iron and one that is thin for cutting hot iron. The hardy, like any other cutting tool, works much better if kept sharp. It may be ground like a cold chisel.

In cutting cold iron, the bar may be deeply nicked on two or more sides and then broken off by bending. In cutting hot iron, it is common practice to cut clear through from one side. Care must be token, of course, not to let the hammer strike the cutting edge of the hardy, or else both the hammer and the hardy may be damaged. In finishing a cut, the last two or three blows should be struck just beyond the cutting edge and not directly over it.

Cutting Tool Steel.—No attempt should be made to cut tool steel in the hardened state. It should always be annealed or softened. To cut it on the hardy, it should be cut hot—not cold—and handled just like other iron or steel.

Where it is imi>ortant to have a smooth cut, a bar of tool steel may be sawed about a quarter of the way through and then broken by clamping in a vise at the sawing line and hammering (see Art. 212, page 146).

298. Estimating Amount of Stock Required.—To estimate the amount of stock required for bends and curves, estimate the length of the center line. For example, suppose it is desired to know how much will be needed for making a ring of }4-inch round stock and of 3 in. inside diameter. The length needed will be the length of the mid-line, halfway between the inside and the outside edges. Its length is equal to the mid-diameter, 3]4 in. times 3.1416, or 11 in.

To determine the length required for pieces of irregular shape, small wire can be bent into the desired shape and then straightened out and measured.

299. Striking with the Hammer.—Success in blacksmithing depends largely upon ability to strike effectively with the hammer. Most black-smithing requires heavy, well-directed blows. Where light blows are better, however, they should be used.

Light blows are struck mostly with motion from the wrist; while heavier blows require both wrist and elbow aetion; and very heavy blows require action from the shoulder in addition to wrist and elbow motion.

To direct hammer blows accurately, strike one or two light taps first, to get the proper direction and feel of the hammer, and then follow with quick, sharp blows of appropriate force or strength. It is also important to use a hammer of appropriate size. A heavy hammer on light work is awkward, and blows cannot be accurately placed. And using a light hammer on heavy work is very slow and tedious.

300. Blacking.—After forging a piece of iron it is a good plan to black it by heating it slightly and rubbing with an oily rag. The iron should not be red, yet it should be hot enough to burn the oil off and prevent a greasy appearance. Blacking the piece gives a better appearance and provides some protection against rusting. Tempered tools, of course, should not be blacked in this manner, as heating will draw the temper.

Fig. 260.—Striking with the hammer. A. Light blows are struck largely with wrtat motion. R. Moderate blows require both elbow and wrist action. C. Heavy blow« require shoulder action M well as wrist and elbow motion.

Fig. 260.—Striking with the hammer. A. Light blows are struck largely with wrtat motion. R. Moderate blows require both elbow and wrist action. C. Heavy blow« require shoulder action M well as wrist and elbow motion.

Fjg. 267.—An iron may be blacked by heating it slightly and rubbing it with an oily rac. The iron should be just hot enough to make the rag smoke. Blacking improves the appearance and affords aome protection against rusting.

Points on Black&mithing

1. A clean, deep, compact fire is the first requirement for good blacksmithing.

2. Put the iroas in the fire in a horizontal position—never point them down into the fire.

3. Use tongs that fit the work. If they do not fit, heat them and reshape the jaws over the piece to be held.

4. Always work the irons at a good forging heat—a bright red or nearly white heat for mild steel.

5. Never allow the irons to get hot enough to sparkle, except in welding, and erven then very little.

C. In bending, nse bending or leverage blows—not mashing blows.

7. In drawing, strike square, direct blows straight down—not forward-pushing, or glancing blows.

8. In drawing round rods, always make them square first and do the drawing while square. When drawn sufficiently, make them eight-sided and finally round.

9. To smooth up a round rod, roll it slowly on the anvil while striking a series of light, quick blows.

10. In pointing rods, work on tlie far edge of the anvil, liaise the back end of the rod and strike with the toe of the hammer tilted down.

11. In upsetting use a high heat, and strike extra-hs/ivy blows.

12. To make a good twist, have the section to be twisted at a uniform temperature.

13. To punch a hole in a hot iron, start in on the flat face of the anvil. Then turn it over and drive the punch back from the other side. Move the iron over a hole in the anvil face for finally driving out the pellet.

14. In cutting on the hardy, be careful not to let the hammer strike the cutting edge.

15. Use the chipping block for cutting with the cold chisel—not the fiat face of the anvil.

16. To estimate the amount of stock required for curved pieces, estimate the length of the mid-line.

17. Strike light hammer blows with wrist motion only; medium blows with motion from both the wrist and the elbow; and heavy blows with motion from tho shoulder, wrist, and elbow.

18. Blacking a forging gives it a better appearance and provides some protection against rust. To black, simply rub the piece with an oily rag when it is just hot enough to make the rag smoke.

Questions

290. (a) What are the main fundamental forging operations? (6) Why is it important to master them thoroughly? (c) What are the main important points to observe in bending iron at the anvil? (<d) How may irons be bent without mashing them? (e) How may square bends be made without marring or galling the iron? (J) How may irons be straightened? (g) What procedure would you use for bending flat irons edgeways?

291* (a) Explain and be able to demonstrate the procedure for making an eye on the end of a rod, (b) If an eye is somewhat oval in shape, how may it best be rounded?

(c) Why is it important to keep the iron at a high forging heat?

292. (a) What is drawing? (6) What are the main import&nt points to be observed in drawing? (c) When, if ever, should forward pushing blows be used in drawing?

(d) What difficulties may arise from hammering the iron too cold? (e) What are tho atepe in the process of drawing round rods? (J) In making a tapered point, why should the iron not be laid flat on the anvil? (g) Why should the hammering be done on the far edge of the anvil face? (h) Why should the toe of the hammer be lower than the heel?

293. (a) What is upsetting and for what purposes is it done? (6) Why should very heavy blows be used in upsetting? (c) How may a very high heat be used and yet confined to only the portion to be upset? (<d) What special ways may be used for upsetting the end of a long heavy bar?

294. (a) How may a twist be neatly made in a bar and confined to a definite part of the bar? (6) Why is a uniform heat especially desirable for twisting? (c) Why is it important to work rapidly in twisting?

296, (a) What advantage is there to be gained by punching a hole rather than drilling it? (b) Just what procedure should be used in punching a hole? (c) Why should the hole be started on the flat face of the anvil rather than over the pritchel hole or hardy hole? (d) How may the punch be kept from sticking in the hole? (e) How may a punch be maneuvered to get it located exactly in the desired position for punching?

296. (a) Just how can a head or shoulder be formed on the end of a bar preparatory to making a punched eye? (b) How may the eye for a chain hook have the corners and edges rounded after the hole is punched?

297. (a) What advantages does cutting with a hardy have over hacksawing? (6) What points should be observed in cutting with a hardy? (e) Can tool steel be cut on a hardy? If so, just how?

298. (a) How may the amount of stock required for a ring be closely estimated? (6) How may the amount of stock required for irregular bends and curves be estimated?

299. (a) Explain and be able to demonstrate just how to hold the hammer and strike light blows; also medium blows and heavy blows, (ib) What difficulties may arise from using a hammer that is too heavy or too light for the work at hand?

300. (a) How may irons be blacked after forging? (b) How hot should they be for blacking? (c) What are the purposes of blacking? (d) May tempered tools be blackened in the same manner as ordinary mild steel?

References

Schwarzkopf: "Plain and Ornamental Forging.'' Radebaugh: "Repairing Farm Machinery." Friese: "Farm Blacksmithing." Haecourt: "Elementary Forge Practice." Boss. Dent, and White: "Mechanical Training." Smith, Robert H.: "Agricultural Mechanics." Selvidge and Allton: "Blacksmithing."

CHAPTER XX

Woodworking Tools and Installation Tips

Woodworking Tools and Installation Tips

There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.

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