A Text-Book of Horseshoeing
by A. Lungwitz and John W. Adams Copyright 1897
This is the third part in what will be a complete reprint of Lungwitz & Adams’ important ‘Textbook of Horse-Shoeing’ originally written in the 1880’s and containing some remarkably modern information. This volume goes into the greatest detail on the subject and with an intelligent clarity that belies how old it is. Coming as it did at the end of the first horse era, and well before anyone might have reasonably predicted the advent of the automobile and tractor, it is apparent how important the equine was to the whole of society. The authors, of Germany and Pennsylvania, compiled what was, at the time, to be the ultimate word on the subject. As with all of the reprints we have offered over forty years time, we trust that readers will be triggered by these words to complete their education with diligence and introspection. Just because something is old doesn’t always make it right, and of course just because something is new doesn’t make it the true culmination. LRM
F. Making Shoes.*
* On a shoe we distinguish an outer and an inner branch. The anterior portion, formed by the union of the two branches is called the toe. The upper surface, upon which the hoof rests, is called the hoof-surface, and the under surface, which is in contact with the ground, the ground-surface. That portion of the hoof-surface which is in direct contact with the lower border of the wall, the white line, and a narrow margin of the sole is termed the bearing-surface, and when necessary “concaving” (seating) extends from this to the inner border of the shoe. On the ground-surface is seen the “fullering” or “crease.”
Besides good, tough iron for the shoe, we need an anvil with a round horn and a small hole at one end, a round-headed turning-hammer, a round sledge, a stamping hammer, a pritchel of good steel, and, if a fullered shoe is to be made, a round fuller. Bodily activity and, above all else, a good eye for measurement are not only desirable, but necessary. A shoe should be made thoughtfully, but yet quickly enough to make the most of the heat.
The iron of which horseshoes are made is derived from the natural iron ore. Iron used for technical purposes is not chemically pure. Pure iron is rather too soft, and is therefore mixed with different substances, mostly with “carbon,” the most important ingredient of our fuel. Of course, the iron contains a very small quantity of carbon (0.5 to 5 percent). When iron contains more than 2.2 percent of carbon it is hard, brittle, and more easily melted, and is known as crude iron, or raw iron, because it is derived from the raw product, — black ore. The melted crude iron is called cast iron. Iron is ductile when it contains less than 2.2 percent of carbon and is then called forge iron, or wrought iron. Wrought iron is fusible only at a high temperature. Only weldable iron containing less than 1.6 percent of carbon is suitable for general use. Of this iron we distinguish two sorts, — steel and wrought iron. A larger percentage of carbon is found in steel than in wrought iron. Steel is hard, can be tempered, and may be called tempered wrought iron. In order to temper or harden steel, bring it to a cherry-red heat, and then cool it suddenly by dipping it in cold water or wet sand. The tempered steel can again be softened as desired by heating and slowly cooling. By heating to a high temperature in a forge wrought iron will become doughy, and may then be intimately united (welded) with another piece at the same temperature by pressure or hammering. This property is called weldability; it is of great importance in making horse-shoes. The heating of iron until it reaches the welding stage is called getting a “heat.” The act of welding wrought iron with steel is called “steeling.”
Regarding the tools, the following hints are sufficient:
The anvil should have a level, smooth, flat steel face.
Likewise, the round head and flat face of both turning-hammer and sledge should be smooth.
On the fullering-hammer (Fig. 101) the left side is flat, the right side convex, and the cutting edge has slightly rounded corners.
The hardy, fullering-hammer, and cold chisel should be flawless on the edge.
The punch (Fig. 102), used to make the nail-holes in the shoe, has a dull point, which should correspond in size with the head of the horseshoe-nail and have slightly rounded corners.
The pritchel (Fig. 103) should not taper to a point, but should end in a rectangular surface whose length is twice its width, in order to punch iron through the shoe under the blow of the hammer.
Making the Shoe.
To make a flat shoe, take the length of the hoof from the point of the toe to the buttress and the greatest width of the hoof; these two measurements, when added together, give the length of the bar for the shoe. The bar should be of such width and thickness as will require the least amount of working. For a bar-shoe or a shoe with heel-calks the bar must be correspondingly longer.
Should we wish to preserve the exact outline of the plantar border of the wall, we may advantageously use such a podometer as is shown in Fig. 104. This consists of a perforated sheet-iron plate one-sixteenth to one-twelfth of an inch thick. This is laid upon the hoof and the outline of the wall marked upon it with chalk.
If necessary, the hoof may be set on a piece of smooth, stiff wrapping paper or card-board, and the outline of the wall closely traced with a lead pencil.
To make a front shoe (Figs. 107 and 108), heat the bar white-hot just beyond its middle, place the head of the sledge hammer across one end of the face of the anvil, hold the unheated end of the bar on the head of the sledge, — the heated end resting on the face of the anvil, and bend the bar into a half-circle with the round head of the turning-hammer. (The outer branch of all shoes is made first; in making pairs the right shoe is made first.) The extreme end of the heated bar is drawn out to the desired width and thickness with the sledge. The bent branch is then placed obliquely across the heel of the horn of the anvil, is turned over toward the right till it rests upon an edge, and is then bevelled diamond-shaped from the toe to the end of the branch. [The edge in contact with the horn is the inner edge of the right branch (outer branch) of the right shoe; the edge beaten down by the hammer is the outer edge of the outer branch.] The branch is then flattened on the anvil because in the bending the outer edge has been stretched and thinned, while the iron of the inner edge has been crowded together (back-set) and thickened. In flattening, the shoe should be left a trifle thinner on the inner edge. The branch is again placed over the horn, and gone over lightly with the flat head of the turning hammer and brought to a proper shape. It is now to be concaved with or without the help of the sledge, or the concaving may be omitted. The concaving should end about three-fourths of an inch from the end of the branch. Now turn the branch and fuller it, or fuller it first and concave afterwards. The fuller should be set in about one-twelfth of an inch from the edge for small shoes, somewhat more for large shoes, and led from the end of the branch towards the toe, twice being necessary to make the fullering of sufficient depth. Next, stamp the holes, punch them through with the pritchel, run over the surfaces, go over the outer edge of the shoe upon the horn, and, finally, hammer the bearing-surface smooth and horizontal. The left branch is made in the same way, except that it is turned to the left and the fullering carried from the toe to the heel. Any ordinary shoe can and should be completed in the rough in two heats. One pair of shoes requires from eight to fifteen minutes.
The hind shoe (Fig. 116) is made in like manner, but the branches are not bent in a circle but given that form shown in Fig. 106. Concaving is not necessary; it is sufficient merely to round the inner edge of the web.
Since in bending the shoe, and especially the toe of a hind shoe, the inner edge is crowded together (back-set) and thickened to the same extent that the outer edge is stretched and thinned, we must remember to do away with these inequalities of thickness and strain by hammering the shoe smooth.
Peculiarities of the Shoe.
They are dependent upon the structure, direction, and position of the leg and hoof, as well as upon the horse’s service and the nature of the ground. Since the shoe is an artificial base of support, and since a proper surface of support is of the greatest importance in preserving the soundness of the feet and legs, careful attention must be given to this matter. Naturally shoes designed for the various forms of hoofs must present equally great and equally numerous differences of form, as well as other peculiarities.
1. Form — A form corresponding to the shape of the hoof is indispensable in every shoe. Front and hind and right and left shoes should be sharply defined and easily distinguishable. Front shoes must, above all else, be circular round at the toe. Hind shoes, on the contrary, should be round pointed at the toe, yet not too much so, but as in Fig. 116.
2. Width — All shoes should be wider webbed (more covered) at the toe than at the ends of the branches. The medium width should be about twice the thickness of the wall.
3. Thickness — Each shoe should, in general terms, be so thick that it need not be renewed under four weeks. Lungwitz found that the average required thickness is about seven-sixteenths of an inch. Of course, this thickness must be diminished or increased according to the rapidity of wear of the shoe. Shoes without calks should be of uniform thickness, unless there are special reasons for making them otherwise.
4. Length — For draft-horses they should be long enough to reach the bulbs of the heel, otherwise shorter, though in other respects they may differ (see “special properties”), but should in all cases completely cover the bearing-surface of the hoof.
5. Surfaces — That part of the hoof-surface of the shoe which is in contact with the hoof (bearing-surface of the shoe, Fig. 109, a) should be horizontal and wide enough to cover the wall, the white line, and from a twelfth to an eighth of an inch of the outer edge of the sole. Shoes for large hoofs require a broader bearing-surface than those for small hoofs. The concaving, or “seating” (Fig. 109, b), should be made deeper or shallower, according to the nature of the sole. Shoes for hoofs with strongly arched (very concave) soles, do not require any concaving (hind hoofs, narrow forehoofs). The object of concaving is to prevent pressure of the shoe upon the horny sole except at its margin.
The ground-surface of the shoe should be flat and perfectly horizontal, except at the toe, which may be turned upward (rolled toe, “rolling motion”).
6. Borders — The outer border should usually be moderately base-narrow — that is, the circumference of the ground-surface of the shoe should be less than the circumference of its hoof-surface; in other words, the entire outer border of the shoe should be bevelled under the foot. Shoes made base-narrow are not so easily loosened, and materially assist in preventing interfering. The inner border should be moderately rounded.
7. The “Fullering” (Fig. 109, c) — In depth it should be about two-thirds the thickness of the shoe, of uniform width, and “clean.” A fullering is not absolutely necessary, but it makes the shoe lighter in proportion to its size, facilitates a uniform placing of the nail-holes, renders the ground-surface somewhat rough, and, because it is rather difficult to make, increases the workman’s skill.
8. Nail-Holes (Fig. 109, d) — The importance of the nail-holes, as regards their character, number, distribution, depth, and direction, cannot be over-estimated, because by the nails which are driven through them the stability of the shoe upon the hoof should be maintained without injuring the sensitive structures, splitting the horny wall, or immoderately interfering with the elasticity of the foot. Each nail-hole should taper uniformly from the ground to the hoof-surface (funnel-shaped). For a medium-weight shoe six nail-holes are sufficient, while for all heavy shoes, especially those with toe- and heel-calks, eight are indicated; however, it should by no means be said that every nail-hole should contain a nail. Hind shoes usually require one more nail-hole than front shoes, yet seldom more than eight. In front shoes the nail-holes should be placed in the anterior half of the shoe (Figs. 107 and 108), while in hind shoes they are to be placed in the anterior two-thirds of the shoe (Fig. 116), and in both cases so distributed that the toe shall be without nail-holes, except in those shoes in which it may be desirable to omit the nail-holes in an entire branch (Fig. 153). The depth of the nail-holes — that is, their distance from the outer edge of the shoe — will depend always upon the thickness of the wall, and should equal the absolute (real) thickness of the wall (Fig. 97). It is evident therefore, that all nail-holes should not be placed at the same depth.
The direction in which the nail-holes should pass through the shoe depends upon the obliquity of the wall. The nail-holes around the toe, as a rule, should incline somewhat inward, the holes at the sides less so while those at the quarters should be punched straight, — that is, should pass perpendicularly through the shoe.
Both front and hind shoes for army horses in time of war and manoeuvres should be so punched that one or two nails may be placed in the posterior half of the shoe (Figs. 111 and 112).
9. Clips (Fig. 113) are half-circular, leaf-like ears drawn upward from the outer edge of the shoe. They should be strong and without flaw at the base, and somewhat higher and thicker upon hind than upon front shoes. Their height on flat shoes should equal the thickness of the shoe, while on shoes with leather soles, or with toe- and heel-calks they should be somewhat higher.
According to their position we distinguish toe- and side-clips. They secure the shoe against shifting; therefore, as a rule, every shoe should have a toe-clip. A side-clip should always be drawn up on that branch of the shoe which first meets the ground in locomotion.
A Shoe with Heel-Calks. — All shoes with heel-calks designed for healthy hoofs should be so made and applied that they will disturb the normal setting down of the foot as little as possible that the wear of the shoe will take place uniformly, and slipping be diminished. The toe of the shoe must, therefore, be left somewhat thicker than the branches just in front of the heel-calks. Moreover, every front shoe with heel-calks must be relatively long, and be provided with considerable rolling motion at the toe; that is, the shoe should be turned up at the toe, the bending beginning near the inner edge of the web. The three- or four-cornered, somewhat conical heel-calks with rounded corners should not be higher than the thickness of the shoe. With reference to the direction of the ends of the branches, we should see to it that they do not rise excessively, but that they assume as near as possible a horizontal direction in passing back to the heels (see Fig. 115).
A Shoe with Toe- and Heel-Calks. — Such a shoe should be of uniform thickness from end to end, and should have a toe-calk and two heel-calks that are somewhat stronger and longer than the heel-calks of a shoe which has no toe-calk. If to a shoe of uniform thickness, on which the heel-calks are somewhat higher than those already described, a piece of steel (Fig. 116, b) of the height of the heel-calks is welded at the toe we have a shoe with toe- and heal-calks. The toe-calk should never be higher than the heel-calks. There are three principal kinds of toe-calks, — namely:
1. The Sharp Toe-Calk. — A bar of toe-steel of proper width and thickness for the toe-calk is thrust with the shoe into the fire. When the end of the bar is cherry-red in color it is withdrawn, laid across the straight hardy, and cut nearly through at a point a calk-length from the end. Bar and shoe are then brought to a welding heat, the calk quickly and securely welded across the toe of the shoe, the bar wrenched away, the calk gone over again with the hammer, when it is immediately beaten out to a sharp edge from the anterior face, either over the far edge of the anvil, or in a foot-vise. The posterior face of a sharp toe-calk should be perpendicular to the ground-surface of the shoe. Machine-made toe-calks, — sharp, half-sharp and blunt, provided with a sharp spud at one or both ends, are in general use. Their use requires two heats, and the sharp calk is blunted in the welding.
2. The Blunt Toe-Calk. — It is a rather long rectangular piece of toe-steel, straight, or curved to conform to the toe of the shoe. The shoe-surface and the ground-surface of the calk are of equal dimensions. It should be welded on in one heat.
3. The Half-Sharp Toe-Calk (Coffin-Lid Toe-Calk). — It resembles the blunt calk, except that the surface of the calk that is applied to the shoe is somewhat broader and longer than the surface that comes in contact with the ground. It is welded on in one heat. The first and third kinds are most suitable for winter.
Since heel- and toe-calks raise the hoof far from the ground and prevent all pressure upon the frog, they diminish the elasticity of the hoof and injure it. They are injurious also to the joints, because they furnish a base of support which is essentially smaller than that afforded by a flat shoe (Fig. 116). However, they are indispensable for heavy draft purposes on slippery roads and in winter. Upon all other roads and in summer they are superfluous, at least upon front hoofs, especially as they do not wholly prevent slipping.
Special Properties. — The many different forms of hoofs require a great variety of shoes. Following are the special peculiarities of each of the chief classes of shoes.
1. Shoe for a Regular Hoof. — Outer edge: moderately base-narrow (bevelled under) all around. Distribution and direction of the nail-holes: regular. Length: longer than the hoof by the thickness of the shoe (see Figs. 121 and 122).
2. Shoe for an Acute-Angled Hoof. — Outer edge: strongly base-narrow around the toe, but gradually becoming perpendicular towards the ends of the branches. Punching: regular, except that the nail-holes at the toe must incline inward somewhat more than usual. Length: rather longer than the preceding shoe (see Fig. 123).
3. Shoe for an Upright (stumpy) Hoof. — Outer edge: perpendicular at the toe; but if the hoof is very steep, then base-wide at the toe, — i.e., bevelled downward and outward. Punching: last nail should be placed just beyond the middle of the shoe. Direction of the holes: perpendicular. Length: short; at most one-eighth of an inch longer than the hoof. In the case of a “bear-foot” (see Fig. 70) the shoe should be long.
4. Shoe for a Base-Wide Hoof. — Outer edge; the outer branch should be moderately base-narrow, — i.e., bevelled downward and inward, the inner branch perpendicular. Punching: upon the outer branch the holes should extend well back, while upon the inner branch they are to be crowded forward towards the toe (see Fig. 117). Length will depend upon the obliquity of the hoof as seen in profile (see Fig. 123).
5. Shoe for a Base-Narrow Hoof. — Outer edge: the outer branch either perpendicular or base-wide, the inner branch strongly base-narrow. Punching: the nail-holes in the outer branch should be crowded towards the toe and, under certain conditions, punched deeper than the wall is thick, on account of the greater width of this branch; in the inner branch the nail-holes are to be distributed back to the quarter and punched light (see Fig. 118). Length will depend upon the obliquity of the hoof. The outer branch should be about one-fourth of an inch longer than the inner.
6. Shoe for a Wide Hoof. — Somewhat wider webbed (more covered) than usual. Outer edge: bevelled under the foot all around (base-narrow). Punching: nail-holes carried back into the posterior half of the shoe (see Fig. 119). Length will depend upon the obliquity of the hoof.
7. Shoe for a Narrow Hoof. — Outer edge: moderately bevelled under the foot at the toe (base-narrow), elsewhere perpendicular. Distribution of the nail-holes: regular. Direction of the nail-holes: perpendicular and towards the quarters, inclining somewhat outward. The holes about the toe incline somewhat inward. Length will depend upon the obliquity of the hoof. Concaving unnecessary (see Fig. 120).
The forms of shoes described in paragraphs 2 to 7 differ from that described in paragraph 1, but are necessary in order to lessen the injurious consequences of irregular loading (unbalancing) of the feet, and of unfavorable bases of support of the body-weight.
G. Choosing the Shoe.
The choice of the shoe for a given horse is not at all difficult after we have carefully considered his weight, the nature of his work, his standing position, gait, the form of his hoofs, and quality of the horn, bearing in mind the general and peculiar properties of shoes. As a rule, we choose a shoe that is longer than the hoof, because the latter grows and carries the shoe forward with it, and because the quarters gradually become lowered by rubbing and wearing away upon the branches of the shoe. The length of the shoe is of especial importance. For horses employed for slow, heavy-draft purposes the shoe supplied with heel- and toe-calks should extend backward far enough to support the bulbs of the heels. On the contrary, horses used at a trot or gallop, as coach- and saddle-horses, require shorter shoes (see Fig. 124).
The weight of the shoe should be so adjusted to the demands of the horse’s work, the condition of the legs (whether used up with work or not), and the nature of the ground that the shoeing will last at least a month. Hard roads and a heavy, clumsy gait require strong, durable shoes, which, under some conditions, are to be rendered still more durable by welding in steel. For moderate service upon soft roads we should use light shoes. Running horses require unusually thin and narrow shoes of steel (see Figs. 125-128).
H. Shaping and Fitting Shoes. General Considerations.
This is one of the most important parts of horseshoeing. Its object is to so fashion or shape the shoe which has been chosen for a particular hoof that its circumference will exactly correspond to the lower circumference of the previously prepared hoof, and its bearing-surface will fit air-tight to the bearing-surface of the hoof. At this time all defects in the surfaces of hoof and shoe and in the nail-holes must be remedied, the clips drawn up, and the shoe made to fit perfectly. The bearing-surface of the shoe, especially at the ends of the branches, must be kept horizontal* and smooth, and its width regulated by the width of the bearing surface of the hoof. Perfectly uniform heating is absolutely indispensable in shaping the shoe, because an irregularly heated shoe twists or becomes distorted at the warm places. Every shoe should be straight, and when held before the eye one branch should exactly cover the other. A flat shoe laid upon a level surface should touch at all parts of its ground-surface; the only exception to this is the shoe with a rolled toe (rolling motion), in which the toe is turned upward. A shoe is termed “trough-shaped” when only the inner edge of the web rests upon the flat surface. It is faulty, disturbs the stability of the foot, and shifts the weight of the body too much upon the quarters.
* The horizontal bearing-surface is in accordance with nature, because the changes of form of the hoof which take place at the plantar border of the wall, on burdening and unburdening the foot, should not be interfered with. A horizontal bearing-surface best fulfills this requirement.
To front shoes we give a rolled toe (Fig. 121, rolling motion), by which we mean a more or less pronounced upward turn of the toe of the shoe. Ordinarily, the toe begins to turn up at the middle of the web, and should be elevated about one-half the thickness of the iron. The rolled toe corresponds to the natural wear of front hoofs, facilitates the “breaking over” of the feet, and insures a uniform wear of the shoe (see Fig. 86). The shoe is made moderately hot and placed on the foot with the toe-clip against the wall exactly in front of the point of the frog. The scorched horn should be repeatedly removed with the rasp until a perfect-fitting bed has been made upon the bearing-surface of the hoof. From the bearing-surface of the shoe to the inner border of the web the iron must be free from the sole around its entire circumference. The horn sole should not be burnt, because the velvety tissue of the sole lies immediately above it. In the region of the nail-holes the outer borders of shoe and wall should correspond. The nail-holes must under all conditions cover the white line. From the last nail-hole back to the ends of the branches for hoofs of the regular standing position of the limbs, the shoe should gradually widen until it projects at each quarter from a sixteenth to an eighth of an inch beyond the edge of the wall. The posterior half of the shoe should, therefore, be somewhat wider than the hoof. The effect of this will be to prolong the usefulness of the shoes. With respect to the width of the branches, an exception arises in the case of hind shoes, in which the inner branch, with few exceptions, should closely follow the border of the wall; this will prevent interfering and tearing off the shoe by the opposite foot.
Between the ends of the branches and the frog there should be enough room, with few exceptions, to pass a foot-pick.
In order to judge of the width of a shoe which has been fitted to the hoof, it is of advantage to seize the hoof in the left hand and, extending it towards the ground, to observe from behind and above the outer border of the shoe and the surfaces of the wall.
Furthermore, the most important rule is that the shoe should always have the form of the foot, so long as the form of the hoof remains unaltered. In all hoofs that have already undergone change of form we must strive to give the shoe that form which the hoof had before it underwent change. Such treatment will not only do the hoof no injury, but, on the contrary, is of advantage to it, as it is well known that in time the hoof will acquire the form of the shoe.
Shaping and Fitting Shoes. Special Considerations.
(a) A shoe for a hoof of the regular form fits properly when the outer border of the shoe in the region of the nail-holes closely follows the outer edge of the wall, but from the last nail-hole to the end of each branch extends beyond the wall from a sixteenth to an eighth of an inch, the shoe is straight, lies firmly and airtight upon the bearing-surface of the hoof, the nail-holes fall exactly upon the white line, and there is sufficient space between the frog and the branches of the shoe for the passage of a foot-pick. The branches must be of equal length.
While in fitting a shoe to a hoof of regular form we need pay attention only to the form of the hoof, it is very different when we come to shape and fit shoes to hoofs of irregular forms. In these cases we must consider not only the form of the hoof, but the position of the limbs and the distribution of weight in the hoof, because where the most weight falls the surface of support of the foot must be widened, and where least weight falls (on the opposite side) the surface of support must be narrowed. In this manner the improper distribution of weight within the hoof (an unbalanced foot) is regulated, — that is, is evenly distributed over the surface of support. The manner in which this is accomplished in the various forms of hoofs is as follows:
(b) An acute-angled hoof requires the shoe described in paragraph 2. The branches must be long, because more of the weight falls in the posterior half of the foot, and long branches extend the surface of support backward, while the surface of support in front is to be diminished by making the toe of the shoe base-narrow, either by turning it up or by beveling it in under the foot. A shoe for an acute-angled hoof fits when it is otherwise related to the hoof as is described in paragraph (a), above.
(c) An upright or stumpy hoof presents exactly reverse conditions with respect to the distribution of weight within the hoof, and is treated in an exactly opposite manner. The surface of support should be increased at the toe and diminished at the quarters. This is accomplished by a shoe possessing the peculiarities described in paragraph 3, whose nail-holes are directed either straight or slightly outward.
(d) A base-wide hoof requires the surface of support to be widened upon the inner side of the foot and narrowed upon the outer side, because the inner half of the foot bears the more weight. A shoe having the peculiarities described in paragraph 4 accomplishes this end.
(e) The base-narrow hoof is just the reverse of the preceding, and requires a shoe whose peculiarities are described in paragraph 5. While in the normal standing position of the limbs, viewed from in front, the ends of the branches of the shoe should be equally distant from the middle of the median lacuna of the frog, this is not so in the base-wide and base-narrow positions. In the base-wide position the outer and in the base-narrow position the inner branch should be somewhat farther from the median lacuna than the branch of the opposite side.
(f ) The wide hoof has too large a surface of support, and, therefore, the shoe designed for it should possess the peculiarities enumerated in paragraph 6.
(g) The narrow hoof has already too narrow a base of support, and must not be made smaller; therefore the shoe should not have a base-narrow but a perpendicular outer border, as described in paragraph 7.