A caulkin from the Latin

Latin

Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 calx

Calx

Calx is a residual substance, sometimes in the form of a fine powder, that is left when a metal or mineral combusts or is calcinated due to heat.Calx, especially of a metal, is now known as an oxide...

(the heel

Heel

In human anatomy, the heel is the prominence at the posterior end of the foot. It is based on the projection of one bone, the calcaneus or heel bone, behind the articulation of the bones of the lower leg.- Human anatomy :...

) is a blunt projection on a horseshoe

Horseshoe

A horseshoe, is a fabricated product, normally made of metal, although sometimes made partially or wholly of modern synthetic materials, designed to protect a horse's hoof from wear and tear. Shoes are attached on the palmar surface of the hooves, usually nailed through the insensitive hoof wall...

 that is often forged, welded or brazed onto the shoe. The term may also refer to traction devices screwed into the bottom of a horseshoe, also commonly called shoe studs or screw-in calks. These are usually a blunt spiked cleat

Cleat

Cleat may refer to:* Cleat , a type or part of a shoe* Cleat , a fitting on ships, boats, and docks to which ropes are tied* Cleats , a comic strip by Bill Hinds...

, usually placed at the sides of the shoe.

Use

Caulkins or studs improve a horse's balance and grip over uneven or slippy terrain, allowing the animal to move better and jump more confidently in poor footing. Screw in calks are most often seen in speed sports, such as eventing

Eventing

Eventing is an equestrian event comprising dressage, cross-country, and show jumping. This event has its roots in a comprehensive cavalry test requiring mastery of several types of riding...

, polo

Polo

Polo is a team sport played on horseback in which the objective is to score goals against an opposing team. Sometimes called, "The Sport of Kings", it was highly popularized by the British. Players score by driving a small white plastic or wooden ball into the opposing team's goal using a...

, and show jumping

Show jumping

Show jumping, also known as "stadium jumping," "open jumping," or "jumpers," is a member of a family of English riding equestrian events that also includes dressage, eventing, hunters, and equitation. Jumping classes commonly are seen at horse shows throughout the world, including the Olympics...

, although they are sometimes used for dressage

Dressage

Dressage is a competitive equestrian sport, defined by the International Equestrian Federation as "the highest expression of horse training." Competitions are held at all levels from amateur to the World Equestrian Games...

. Forged caulks of various styles more often seen on race horses

Horse racing

Horse racing is an equestrian sport that has a long history. Archaeological records indicate that horse racing occurred in ancient Babylon, Syria, and Egypt. Both chariot and mounted horse racing were events in the ancient Greek Olympics by 648 BC...

 and on working animals such as draft horse

Draft horse

A draft horse , draught horse or dray horse , less often called a work horse or heavy horse, is a large horse bred for hard, heavy tasks such as ploughing and farm labour...

s and some packhorse

Packhorse

.A packhorse or pack horse refers generally to an equid such as a horse, mule, donkey or pony used for carrying goods on their backs, usually carried in sidebags or panniers. Typically packhorses are used to cross difficult terrain, where the absence of roads prevents the use of wheeled vehicles. ...

s and trail horses, though in some areas they are still seen on field hunter

Field hunter

A field hunter, or a fox hunter, is a type of horse used in the hunt field for fox hunting. It may be of any breed, but should possess stamina, a level head, and bravery. The horse should have a safe jump, so as not to get caught on any of the solid obstacles found in the hunt field...

s and other riding horses that have to work in all weather and require extra traction, such as police horses.

Permanent designs

Traditionally, the prongs of an elongated horseshoe (commonly not more than 1.75 inches or 45 mm) have tips bent at an acute angle opposite to the surface attached to the horses' hoof

Hoof

A hoof , plural hooves or hoofs , is the tip of a toe of an ungulate mammal, strengthened by a thick horny covering. The hoof consists of a hard or rubbery sole, and a hard wall formed by a thick nail rolled around the tip of the toe. The weight of the animal is normally borne by both the sole...

. Traditionally, a farrier

Farrier

A farrier is a specialist in equine hoof care, including the trimming and balancing of horses' hooves and the placing of shoes on their hooves...

 employs a forge

Forge

A forge is a hearth used for forging. The term "forge" can also refer to the workplace of a smith or a blacksmith, although the term smithy is then more commonly used.The basic smithy contains a forge, also known as a hearth, for heating metals...

 in hot-shoeing to heat the two heel prongs to red hot and bends them by hammering prongs over a right-angle to bend into an acute angle. Occasionally, another caulkin is on the toe of the shoe and integrally formed in the initial forging process

For a horseshoe built as a concave caulk and wedge shoe, the 2 prongs differ: one prong ends with a caulkin, and the other prong ends with a wedge (with both facing downward to the ground). That caulk/wedge horseshoe is a traditional British hunting shoe, and it has been used to provide the horse with a sure-footed grip when working at a fast pace over uneven ground. The shapes of the caulkin and the wedge have been designed to provide hoof traction, meanwhile ensuring the horse's safety is not compromised. The caulk/wedge horseshoe design has been recognised by the Worshipful Company of Farriers

Worshipful Company of Farriers

The Worshipful Company of Farriers is one of the Livery Companies of the City of London. The Farriers, or horseshoe makers, organised in 1356. It received a Royal Charter of incorporation in 1674. Over the years, the Company has evolved from a trade association for horseshoe makers into an...

 as being an appropriate specimen horseshoe to be used for the diploma exam.

Another way caulkins are applied is for borium

Borium

Borium is a generic name for tungsten carbide granules embedded in a matrix of softer metal. Borium® is a registered trademark of Stoody Deloro Stellite, Inc., for a "Metal Alloy of Exceeding Hardness and Used For Drilling, Boring, and the Like". Borium is used in farriery to improve traction for...

 to be brazed onto the surface of the shoe. Usually borium is placed at the heels and toe, either in small knobs for maximum grip, or in small rough patches for extra traction and to prevent wear on the shoe.

Screw in calks

For use of screw-in calks or studs, horseshoes are "tapped," or drilled, on either heel of the shoe, so that different studs may be applied as needed and changed according to the footing conditions and the type of work performed by the horse. Therefore, a horse may have a maximum of 8 studs (2 per foot). Studs come in several sizes and types.

Screw-in calks or studs are popular in sport competition because they can be changed to adapt to different terrain. However, the size and design of stud must be carefully selected, as the wrong stud will be useless and can damage the horse's legs. Too little traction, and the horse may slip and possibly fall. Too much, and the horse is jarred, as his feet cannot naturally slip (which is a shock-absorption mechanism). Additionally, the more stud used, the greater chance the shoe may be pulled off. Usually, if there is doubt, it is considered best to slightly understud. In general, the faster the pace, the larger the stud will be used. Therefore, small studs are used for dressage and lower-level jumping or eventing, and larger studs are used for polo and upper-level eventing. Studs with more of a point are used for hard ground, and those that have more circumference are used in "heavier" footing, such as thick mud.

A hoof pick or horseshoe nail can help remove the plug prior to insertion of a screw-in stud. A special instrument called a T-tap is used to clean out the stud holes before the stud is screwed in, or it can be used to re-tap the stud hole if the threads are damaged. Additionally, a small metal brush can be used to help clean threads which are especially dirty. A wrench is used to tighten or loosen the studs.

Types of studs

Type	Description
Road studs	used on hard surfaces, usually 4 or 6-sided, smaller in size and blunt. Can be used front or back, on the inside of the shoe or the outside. This type of stud is fine most of the time, unless the ground is incredibly muddy or slippery.
Blocks	square in shape and best for soft, deep, muddy ground.
Bullets	best for firm ground with a layer of soft ground on top. They are large and sharp.
Grass Studs	narrow and sharp to dig into hard, dry ground. They should only be used on the outside of the shoe, or just on the hind feet.
Olympic studs	used for extremely slippery ground, very long and sharp.

Safety

Caulkins forged into the shoe which are not removable pose an increased risk of injury to handler or horse should the horse step on or kick a person, itself, or another animal. When stable

Stable

A stable is a building in which livestock, especially horses, are kept. It most commonly means a building that is divided into separate stalls for individual animals...

d, animals wearing caulkins need extra bedding to avoid abrasion when lying down and for protection while moving about in a confined area. When working, leg protection in the form of bell boots

Bell boots

Bell boots, or overreach boots, are a type of protective boot worn by a horse. They encircle the horse's ankle, and protect the back of the pastern and the heels of the animal.-Uses of Bell Boots:...

 and splint boots or polo wraps may minimize the risk of injury.

Screw-in studs are often longer and sharper than permanent caulkins and thus are removed when the horse is not working. The hole for the stud is plugged with cotton, rubber plugs, or a stud blank so dirt does not ruin the threads of the hole. Due to risk of injury, horse are not shipped in studs or left unattended with studs screwed in.

Pointed studs, such as grass studs or pointed bullets are generally placed only on the outside of the shoe, so the horse is less likely to cut himself should his foot hit one of his legs. Road stud can be used on the inside or outside of a shoe. However, the shoe should have some stud on the inside of the shoe; without it, there will be a twisting motion on the foot, which can cause a loss of shoe, and possibly strain the legs. Most riders place smaller studs on the front feet, because the horse, being a "rear-engine" animal, generally requires more traction behind.

External links

• Historical development of the horseshoe 1891 Scientific American
  Scientific American
  Scientific American is a popular science magazine. It is notable for its long history of presenting science monthly to an educated but not necessarily scientific public, through its careful attention to the clarity of its text as well as the quality of its specially commissioned color graphics...
  
   article from Project Gutenberg
  Project Gutenberg
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