Rope - AbsoluteAstronomy.com

A rope is a length of fibres, twisted or braid

Braid

A braid is a complex structure or pattern formed by intertwining three or more strands of flexible material such as textile fibres, wire, or human hair...

ed together to improve strength for pulling and connecting. It has tensile strength

Tensile strength

Ultimate tensile strength , often shortened to tensile strength or ultimate strength, is the maximum stress that a material can withstand while being stretched or pulled before necking, which is when the specimen's cross-section starts to significantly contract...

but is too flexible to provide compressive strength

Compressive strength

Compressive strength is the capacity of a material or structure to withstand axially directed pushing forces. When the limit of compressive strength is reached, materials are crushed. Concrete can be made to have high compressive strength, e.g...

(i.e. it can be used for pulling, but not pushing). Rope is thicker and stronger than similarly constructed cord, line, string

Twine

Twine is a light string or strong thread composed of two or more smaller strands or yarns twisted together. More generally, the term can be applied to any thin cord....

, and twine

Twine

Twine is a light string or strong thread composed of two or more smaller strands or yarns twisted together. More generally, the term can be applied to any thin cord....

Construction

Common materials for rope include natural fibres such as manila hemp

Manila hemp

Manila hemp, also known as manilla, is a type of fiber obtained from the leaves of the abacá , a relative of the banana. It is mostly used for pulping for a range of uses, including speciality papers. It was once used mainly to make manila rope, but this is now of minor importance...

, hemp

Hemp

Hemp is mostly used as a name for low tetrahydrocannabinol strains of the plant Cannabis sativa, of fiber and/or oilseed varieties. In modern times, hemp has been used for industrial purposes including paper, textiles, biodegradable plastics, construction, health food and fuel with modest...

, linen

Linen

Linen is a textile made from the fibers of the flax plant, Linum usitatissimum. Linen is labor-intensive to manufacture, but when it is made into garments, it is valued for its exceptional coolness and freshness in hot weather....

, cotton

Cotton

Cotton is a soft, fluffy staple fiber that grows in a boll, or protective capsule, around the seeds of cotton plants of the genus Gossypium. The fiber is almost pure cellulose. The botanical purpose of cotton fiber is to aid in seed dispersal....

, coir

Coir

Coir is a natural fibre extracted from the husk of coconut and used in products such as floor mats, doormats, brushes, mattresses etc. Technically coir is the fibrous material found between the hard, internal shell and the outer coat of a coconut. Other uses of brown coir are in upholstery...

, jute

Jute

Jute is a long, soft, shiny vegetable fibre that can be spun into coarse, strong threads. It is produced from plants in the genus Corchorus, which has been classified in the family Tiliaceae, or more recently in Malvaceae....

, and sisal

Sisal

Sisal is an agave that yields a stiff fibre traditionally used in making twine, rope and also dartboards. The term may refer either to the plant or the fibre, depending on context...

.

Synthetic fibres in use for rope-making include polypropylene

Polypropylene

Polypropylene , also known as polypropene, is a thermoplastic polymer used in a wide variety of applications including packaging, textiles , stationery, plastic parts and reusable containers of various types, laboratory equipment, loudspeakers, automotive components, and polymer banknotes...

, nylon

Nylon

Nylon is a generic designation for a family of synthetic polymers known generically as polyamides, first produced on February 28, 1935, by Wallace Carothers at DuPont's research facility at the DuPont Experimental Station...

, polyester

Polyester

Polyester is a category of polymers which contain the ester functional group in their main chain. Although there are many polyesters, the term "polyester" as a specific material most commonly refers to polyethylene terephthalate...

s (e.g. PET

Polyethylene terephthalate

Polyethylene terephthalate , commonly abbreviated PET, PETE, or the obsolete PETP or PET-P, is a thermoplastic polymer resin of the polyester family and is used in synthetic fibers; beverage, food and other liquid containers; thermoforming applications; and engineering resins often in combination...

, LCP

Liquid crystal polymer

Liquid-crystal polymers are a class of aromatic polyester polymers. They are extremely unreactive and inert, and highly resistant to fire.-Background:...

, HPE, Vectran

Vectran

Vectran is a manufactured fibre, spun from a liquid crystal polymer created by Celanese Acetate LLC and now manufactured by Kuraray Co., Ltd. Chemically it is an aromatic polyester produced by the polycondensation of 4-hydroxybenzoic acid and 6-hydroxynaphthalene-2-carboxylic acid.- Properties...

), polyethylene

Polyethylene

Polyethylene or polythene is the most widely used plastic, with an annual production of approximately 80 million metric tons...

(e.g. Dyneema & Spectra), Aramid

Aramid

Aramid fibers are a class of heat-resistant and strong synthetic fibers. They are used in aerospace and military applications, for ballistic rated body armor fabric and ballistic composites, in bicycle tires, and as an asbestos substitute. The name is a portmanteau of "aromatic polyamide"...

s (e.g. Twaron

Twaron

Twaron is the brandname of Teijin Aramid for a para-aramid. It is a heat-resistant and strong synthetic fibre developed in the early 1970s by the Dutch company AKZO, division Enka, later Akzo Industrial Fibers. The research name of the para-aramid fibre was originally Fiber X, but it was soon...

, Technora

Technora

Technora is an Aramid that is useful for a variety of applications that require high strength or chemical resistance. It is a brandname of the company Teijin.-Production:...

and Kevlar

Kevlar

Kevlar is the registered trademark for a para-aramid synthetic fiber, related to other aramids such as Nomex and Technora. Developed at DuPont in 1965, this high strength material was first commercially used in the early 1970s as a replacement for steel in racing tires...

) and acrylics (e.g. Dralon). Some ropes are constructed of mixtures of several fibres or use co-polymer fibres. Rope can also be made out of metal

Wire rope

thumb|Steel wire rope Wire rope is a type of rope which consists of several strands of metal wire laid into a helix. Initially wrought iron wires were used, but today steel is the main material used for wire ropes....

. Ropes have been constructed of other fibrous materials such as silk

Silk

Silk is a natural protein fiber, some forms of which can be woven into textiles. The best-known type of silk is obtained from the cocoons of the larvae of the mulberry silkworm Bombyx mori reared in captivity...

, wool

Wool

Wool is the textile fiber obtained from sheep and certain other animals, including cashmere from goats, mohair from goats, qiviut from muskoxen, vicuña, alpaca, camel from animals in the camel family, and angora from rabbits....

, and hair, but such ropes are not generally available. Rayon

Rayon

Rayon is a manufactured regenerated cellulose fiber. Because it is produced from naturally occurring polymers, it is neither a truly synthetic fiber nor a natural fiber; it is a semi-synthetic or artificial fiber. Rayon is known by the names viscose rayon and art silk in the textile industry...

is a regenerated fibre used to make decorative rope.

Usage

Rope is of paramount importance in fields as diverse as construction

Construction

In the fields of architecture and civil engineering, construction is a process that consists of the building or assembling of infrastructure. Far from being a single activity, large scale construction is a feat of human multitasking...

, seafaring, exploration, sports and communications and has been since prehistoric

Prehistory

Prehistory is the span of time before recorded history. Prehistory can refer to the period of human existence before the availability of those written records with which recorded history begins. More broadly, it refers to all the time preceding human existence and the invention of writing...

times. In order to fasten rope, a large number of knot

Knot

A knot is a method of fastening or securing linear material such as rope by tying or interweaving. It may consist of a length of one or several segments of rope, string, webbing, twine, strap, or even chain interwoven such that the line can bind to itself or to some other object—the "load"...

s have been invented for countless uses. Pulley

Pulley

A pulley, also called a sheave or a drum, is a mechanism composed of a wheel on an axle or shaft that may have a groove between two flanges around its circumference. A rope, cable, belt, or chain usually runs over the wheel and inside the groove, if present...

s are used to redirect the pulling force to another direction, and may be used to create mechanical advantage

Mechanical advantage

Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system. Ideally, the device preserves the input power and simply trades off forces against movement to obtain a desired amplification in the output force...

, allowing multiple strands of rope to share a load and multiply the force applied to the end. Winch

Winch

A winch is a mechanical device that is used to pull in or let out or otherwise adjust the "tension" of a rope or wire rope . In its simplest form it consists of a spool and attached hand crank. In larger forms, winches stand at the heart of machines as diverse as tow trucks, steam shovels and...

es and capstan

Capstan (nautical)

A capstan is a vertical-axled rotating machine developed for use on sailing ships to apply force to ropes, cables, and hawsers. The principle is similar to that of the windlass, which has a horizontal axle.- History :...

s are machines designed to pull ropes.

Rock climbing ropes

The modern sport of rock climbing

Rock climbing

Rock climbing also lightly called 'The Gravity Game', is a sport in which participants climb up, down or across natural rock formations or artificial rock walls. The goal is to reach the summit of a formation or the endpoint of a pre-defined route without falling...

makes extensive use of so called "dynamic" rope

Dynamic rope

A dynamic rope is a specially constructed, stretchable rope. This 'stretch' is what makes it 'dynamic', in contrast to a static rope that doesn't have any give when under load. By stretching under load, a dynamic rope will soften the impact of extreme stresses on it, such as falls, and lessens the...

, which is designed to stretch under load in an elastic manner in order to absorb the energy required to arrest a person in free fall

Fall arrest

Fall arrest is the form of fall protection which involves the safe stopping of a person already falling. It is one of several forms of fall protection, forms which also include fall guarding and fall restraint Fall arrest is the form of fall protection which involves the safe stopping of a person...

without generating forces high enough to injure them. Such ropes normally use a kernmantle

Kernmantle rope

Kernmantle rope is rope constructed with its interior core protected with a woven exterior sheath that is designed to optimize strength, durability, and flexibility. The core fibers provide the tensile strength of the rope, while the sheath protects the core from abrasion during use...

construction, as described below. "Static" ropes, used for example in caving, rappelling, and rescue applications, are designed for minimal stretch; they are not designed to arrest free falls. The UIAA, in concert with the CEN

European Committee for Standardization

The European Committee for Standardization or Comité Européen de Normalisation , is a non-profit organisation whose mission is to foster the European economy in global trading, the welfare of European citizens and the environment by providing an efficient infrastructure to interested parties for...

, sets climbing-rope standards and oversees testing. Any rope bearing a GUIANA or CE certification tag is suitable for climbing. Despite the hundreds of thousands of falls climbers suffer every year, there are few recorded instances of a climbing rope breaking in a fall, the cases that do are often attributable to previous damage to, or contamination of, the rope. Climbing ropes, however, do cut easily when under load. Keeping them away from sharp rock edges is imperative.

Rock climbing ropes come with either a designation for single, double or twin use. A single rope is the most common and it is intended to be used by itself, as a single strand. Single ropes range in thickness from roughly 9 mm to 11 mm. Smaller ropes are lighter, but wear out faster. Double ropes are thinner ropes, usually 9mm and under, and are intended to be used as a pair. These ropes offer a greater margin or security against cutting, since it is unlikely that both ropes will be cut, but complicate belaying

Belaying

thumb|200px|right|A belayer is belaying behind a lead climberBelaying refers to a variety of techniques used in climbing to exert friction on a climbing rope so that a falling climber does not fall very far...

and leading. Double ropes are usually reserved for ice and mixed climbing, where there is need for two ropes to rappel or abseil. They are also popular among traditional climbers, and particularly in the UK, due to the ability to clip each rope into alternating pieces of protection; allowing the ropes to stay straighter and hence reduce rope drag.
Twin ropes are not to be confused with double's. When using twin ropes, both ropes are clipped into the same piece of protection, treating the two as a single strand. This would be favourable in a situation where there was a high chance of a rope being cut. However new lighter-weight ropes with greater safety have virtually replaced this type of rope.

The butterfly coil

Butterfly coil

The Butterfly coil is a method used by climbers for carrying a rope that is not attached to harness, unlike the Alpine Coil. It is most useful when one can approach an anchor point without needing the coiled rope itself. It is also known as a Backpacker's coil.-Overview:Starting with the two free...

is a method of carrying a rope used by climbers where the rope remains attached to the climber and ready to be uncoiled at short notice. Another method of carrying a rope is the Alpine coil

Alpine coil

The Alpine coil is a method used by climbers for carrying a rope, such that the rope remains attached to harnesses and ready for use. It is also known as a mountaineer's coil....

Aerial rope

Rope is also an Aerial acrobatics

Corde lisse

Corde lisse is an aerial circus skill or act that involves acrobatics on a vertically hanging rope. The name is French for "smooth rope".- Description :...

circus skill, where a performer makes artistic figures on a vertical suspended rope. Tricks performed on the rope are for example drops, rolls and hangs. See also Corde Lisse

Corde lisse

Corde lisse is an aerial circus skill or act that involves acrobatics on a vertically hanging rope. The name is French for "smooth rope".- Description :...

History

The use of ropes for hunting, pulling, fastening, attaching, carrying, lifting, and climbing dates back to prehistoric times. It is likely that the earliest "ropes" were naturally occurring lengths of plant fibre, such as vines, followed soon by the first attempts at twisting and braiding these strands together to form the first proper ropes in the modern sense of the word. Impressions of cordage found on fired clay

Pit fired pottery

Pit firing is the oldest known method for the firing of pottery. Examples have been dated as early as 29,000–25,000 BCE. Kilns have since replaced pit firing as the most widespread method of firing pottery, although the technique still finds limited use amongst certain studio potters.Unfired...

provide evidence of string and rope-making technology in Europe dating back 28,000 years. Fossil

Fossil

Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

ized fragments of "probably two-ply laid rope of about 7 mm diameter" were found in one of the caves at Lascaux

Lascaux

Lascaux is the setting of a complex of caves in southwestern France famous for its Paleolithic cave paintings. The original caves are located near the village of Montignac, in the department of Dordogne. They contain some of the best-known Upper Paleolithic art. These paintings are estimated to be...

, dating to approximately 15,000 BC.

The ancient Egypt

Ancient Egypt

Ancient Egypt was an ancient civilization of Northeastern Africa, concentrated along the lower reaches of the Nile River in what is now the modern country of Egypt. Egyptian civilization coalesced around 3150 BC with the political unification of Upper and Lower Egypt under the first pharaoh...

ians were probably the first civilization to develop special tools to make rope. Egyptian rope dates back to 4000 to 3500 B.C. and was generally made of water reed fibres. Other rope in antiquity was made from the fibres of date palm

Date Palm

The date palm is a palm in the genus Phoenix, cultivated for its edible sweet fruit. Although its place of origin is unknown because of long cultivation, it probably originated from lands around the Persian Gulf. It is a medium-sized plant, 15–25 m tall, growing singly or forming a clump with...

s, flax

Flax

Flax is a member of the genus Linum in the family Linaceae. It is native to the region extending from the eastern Mediterranean to India and was probably first domesticated in the Fertile Crescent...

, grass

Grass

Grasses, or more technically graminoids, are monocotyledonous, usually herbaceous plants with narrow leaves growing from the base. They include the "true grasses", of the Poaceae family, as well as the sedges and the rushes . The true grasses include cereals, bamboo and the grasses of lawns ...

, papyrus

Papyrus

Papyrus is a thick paper-like material produced from the pith of the papyrus plant, Cyperus papyrus, a wetland sedge that was once abundant in the Nile Delta of Egypt....

, leather

Leather

Leather is a durable and flexible material created via the tanning of putrescible animal rawhide and skin, primarily cattlehide. It can be produced through different manufacturing processes, ranging from cottage industry to heavy industry.-Forms:...

, or animal hair. The use of such ropes pulled by thousands of workers allowed the Egyptians

Egyptians

Egyptians are nation an ethnic group made up of Mediterranean North Africans, the indigenous people of Egypt.Egyptian identity is closely tied to geography. The population of Egypt is concentrated in the lower Nile Valley, the small strip of cultivable land stretching from the First Cataract to...

to move the heavy stones required to build their monuments. Starting from approximately 2800 B.C., rope made of hemp

Hemp

fibres was in use in China. Rope and the craft of rope making spread throughout Asia, India, and Europe over the next several thousand years.

In the Middle Ages (from the 13th to the 18th centuries), from the British Isles to Italy, ropes were constructed in so-called Ropewalk
Ropewalk
A ropewalk is a long straight narrow lane, or a covered pathway, where long strands of material were laid before being twisted into rope.Ropewalks historically were harsh sweatshops, and frequently caught on fire, as hemp dust forms an explosive mixture. Rope was essential in sailing ships and the...

s, very long buildings where strands the full length of the rope were spread out and then laid up or twisted together to form the rope. The cable length was thus set by the length of the available rope walk. This is related to the unit of length termed cable length
Cable length
A cable length or cable's length is a nautical unit of measure equal to one tenth of a nautical mile or 100 fathoms, or sometimes 120 fathoms. The unit is named after the length of a ship's anchor cable in the age of sail...

. This allowed for long ropes of up to 300 yards long or longer to be made. These long ropes were necessary in shipping as short ropes would require splicing

Rope splicing

Rope splicing in ropework is the forming of a semi-permanent joint between two ropes or two parts of the same rope by partly untwisting and then interweaving their strands. Splices can be used to form a stopper at the end of a line, to form a loop or an eye in a rope, or for joining two ropes...

to make them long enough to use for sheets

Sheet (sailing)

In sailing, a sheet is a line used to control the movable corner of a sail.- Fore-and-aft rigs:Fore-and-aft rigs comprise the vast majority of sailing vessels in use today, including effectively all dinghies and yachts. The sheet on a fore-and-aft sail controls the angle of the sail to the wind,...

and halyards. The strongest form of splicing is the short splice

Rope splicing

, which doubles the diameter of the rope at the area of the splice, which would cause problems in running the line through pulleys. Any splices narrow enough to maintain smooth running would be less able to support the required weight.

Leonardo da Vinci

Leonardo da Vinci

Leonardo di ser Piero da Vinci was an Italian Renaissance polymath: painter, sculptor, architect, musician, scientist, mathematician, engineer, inventor, anatomist, geologist, cartographer, botanist and writer whose genius, perhaps more than that of any other figure, epitomized the Renaissance...

drew sketches of a concept for a ropemaking machine, but it was never built. Nevertheless, remarkable feats of construction were accomplished without advanced technology: In 1586, Domenico Fontana

Domenico Fontana

Domenico Fontana was a Swiss-born Italian architect of the late Renaissance.-Biography:200px|thumb|Fountain of Moses in Rome....

erected the 327 ton obelisk

Obelisk

An obelisk is a tall, four-sided, narrow tapering monument which ends in a pyramid-like shape at the top, and is said to resemble a petrified ray of the sun-disk. A pair of obelisks usually stood in front of a pylon...

on Rome's Saint Peter's Square

Saint Peter's Square

Saint Peter's Square is located directly in front of St. Peter's Basilica in Vatican City, the papal enclave within Rome .-History of St...

with a concerted effort of 900 men, 75 horses, and countless pulleys and meters of rope. By the late 18th century several working machines had been built and patented.

Some rope continues to be made from natural fibres such as coir

Coir

and sisal

Sisal

Sisal is an agave that yields a stiff fibre traditionally used in making twine, rope and also dartboards. The term may refer either to the plant or the fibre, depending on context...

, despite the dominance of synthetic fibres such as nylon

Nylon

and polypropylene

Polypropylene

which have become popular since the 1950s.

Laid or twisted rope

Laid rope, also called twisted rope, is historically the prevalent form of rope, at least in modern western

Western culture

Western culture, sometimes equated with Western civilization or European civilization, refers to cultures of European origin and is used very broadly to refer to a heritage of social norms, ethical values, traditional customs, religious beliefs, political systems, and specific artifacts and...

history. Common twisted rope generally consists of three strands and is normally right-laid, or given a final right-handed twist. The ISO 2

ISO 2

ISO 2 is an international standard for direction of twist designation for yarns, complex yarns, slivers, slubbings, rovings, cordage, and related products. The standard uses capital letters S and Z to indicate the direction of twist...

standard uses the uppercase letters

Latin alphabet

The Latin alphabet, also called the Roman alphabet, is the most recognized alphabet used in the world today. It evolved from a western variety of the Greek alphabet called the Cumaean alphabet, which was adopted and modified by the Etruscans who ruled early Rome...

S and Z to indicate the two possible directions of twist, as suggested by the direction of slant of the central portions of these two letters. The handedness

Chirality (physics)

A chiral phenomenon is one that is not identical to its mirror image . The spin of a particle may be used to define a handedness for that particle. A symmetry transformation between the two is called parity...

of the twist is the direction of the twists as they progress away from an observer. Thus Z-twist rope is said to be right-handed, and S-twist to be left-handed.

Twisted ropes are built up in three steps. First, fibres are gathered and spun

Spinning (textiles)

Spinning is a major industry. It is part of the textile manufacturing process where three types of fibre are converted into yarn, then fabric, then textiles. The textiles are then fabricated into clothes or other artifacts. There are three industrial processes available to spin yarn, and a...

into yarn

Yarn

Yarn is a long continuous length of interlocked fibres, suitable for use in the production of textiles, sewing, crocheting, knitting, weaving, embroidery and ropemaking. Thread is a type of yarn intended for sewing by hand or machine. Modern manufactured sewing threads may be finished with wax or...

s. A number of these yarns are then formed into strands by twisting. The strands are then twisted together to lay the rope. The twist of the yarn is opposite to that of the strand, and that in turn is opposite to that of the rope. It is this counter-twist, introduced with each successive operation, which holds the final rope together as a stable, unified object.

Traditionally, a three strand laid rope is called a plain- or hawser
Hawser
Hawser is a nautical term for a thick cable or rope used in mooring or towing a ship. A hawser passes through a hawsehole, also known as a cat hole, located on the hawse....

-laid, a four strand rope is called shroud-laid, and a larger rope formed by counter-twisting three or more multi-strand ropes together is called cable-laid.

One property of laid rope is partial untwisting when used. This can cause spinning of suspended loads, or stretching

Deformation (mechanics)

Deformation in continuum mechanics is the transformation of a body from a reference configuration to a current configuration. A configuration is a set containing the positions of all particles of the body...

, kink

Kink

* A twist or bend in something such as rope, cable, hair or IG curveKink or KINK can refer to:* Kink , a colloquial term for non-normative sexual behavior...

ing, or hockling of the rope itself. An additional drawback of twisted construction is that every fibre is exposed to abrasion numerous times along the length of the rope. This means that the rope can degrade to numerous inch-long fibre fragments, which is not easily detected visually.

Twisted ropes have a preferred direction for coil

Coil

A coil is a series of loops. A coiled coil is a structure in which the coil itself is in turn also looping.-Electromagnetic coils:An electromagnetic coil is formed when a conductor is wound around a core or form to create an inductor or electromagnet...

ing. Normal right-laid rope should be coiled with the sun, or clockwise, to prevent kinking. Coiling this way imparts a twist to the rope. Rope of this type must be bound at its ends by some means to prevent untwisting.

Braided rope

Braid

A braid is a complex structure or pattern formed by intertwining three or more strands of flexible material such as textile fibres, wire, or human hair...

ed ropes are generally made from nylon

Nylon

, polyester

Polyester

, polypropylene

Polypropylene

or high performance fibers such as Dyneema, Technora or Vectran. Nylon is chosen for its elastic stretch properties though it has limited resistance to ultraviolet

Ultraviolet

Ultraviolet light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than X-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV...

light. Polyester is about 90% as strong as nylon but stretches less under load, is more abrasion resistant, has better UV resistance, and has less change in length when wet. Polypropylene is preferred for low cost and light weight (it floats on water).

Braided ropes (and objects like garden hose

Hose (tubing)

A hose is a hollow tube designed to carry fluids from one location to another. Hoses are also sometimes called pipes , or more generally tubing...

s, fibre optic or coaxial

Coaxial cable

Coaxial cable, or coax, has an inner conductor surrounded by a flexible, tubular insulating layer, surrounded by a tubular conducting shield. The term coaxial comes from the inner conductor and the outer shield sharing the same geometric axis...

cables, etc.) that have no lay, or inherent twist, will uncoil better if coiled into figure-8 coils, where the twist reverses regularly and essentially cancels out.

Single braid consists of an even number of strands, eight or twelve being typical, braided into a circular pattern with half of the strands going clockwise and the other half going anticlockwise. The strands can interlock with either twill

Twill

Twill is a type of textile weave with a pattern of diagonal parallel ribs . This is done by passing the weft thread over one or more warp threads and then under two or more warp threads and so on, with a "step" or offset between rows to create the characteristic diagonal pattern. Because of this...

or plain weave

Plain weave

Plain weave is the most basic of three fundamental types of textile weaves . It is strong and hard-wearing, used for fashion and furnishing fabrics....

. The central void may be large or small; in the former case the term hollow braid is sometimes preferred.

Double braid, also called braid on braid, consists of an inner braid filling the central void in an outer braid, that may be of the same or different material. Often the inner braid fibre is chosen for strength while the outer braid fibre is chosen for abrasion resistance.

In solid braid the strands all travel the same direction, clockwise or anticlockwise, and alternate between forming the outside of the rope and the interior of the rope. This construction is popular for general purpose utility rope but rare in specialized high performance line.
Kernmantle rope has a core (kern) of long twisted fibres in the center, with a braided outer sheath or mantle of woven

Weaving

Weaving is a method of fabric production in which two distinct sets of yarns or threads are interlaced at right angles to form a fabric or cloth. The other methods are knitting, lace making and felting. The longitudinal threads are called the warp and the lateral threads are the weft or filling...

fibres. The kern provides most of the strength (about 70%), while the mantle protects the kern and determines the handling properties of the rope (how easy it is to hold, to tie knots in, and so on). In dynamic climbing line

Dynamic rope

, the core fibres are usually twisted, and chopped into shorter lengths which makes the rope more stretchy. Static kernmantle ropes are made with untwisted core fibres and tighter braid, which causes them to be stiffer in addition to limiting the stretch.

Other types

Plaited rope is made by braiding twisted strands, and is also called square braid. It is not as round as twisted rope and coarser to the touch. It is less prone to kinking than twisted rope and, depending on the material, very flexible and therefore easy to handle and knot. This construction exposes all fibres as well, with the same drawbacks as described above. Brait rope is a combination of braided and plaited, a non-rotating alternative to laid three-strand ropes. Due to its excellent energy-absorption characteristics, it is often used by arborist

Arborist

An arborist, or arboriculturist, is a professional in the practice of arboriculture, which is the cultivation, management, and study of individual trees, shrubs, vines, and other perennial woody plants...

s. It is also a popular rope for anchoring and can be used as mooring warps. This type of construction was pioneered by Yale Cordage.

Endless winding rope is made by winding single strands of high-performance yarns around two end terminations until the desired break strength or stiffness has been reached. This type of rope (often specified as cable to make the difference between a braided or twined construction) has the advantage of having no construction stretch as is the case with above constructions. Endless winding is pioneered by SmartRigging and FibreMax.

Handling rope

Rope made from hemp

Hemp

, cotton or nylon is generally stored in a cool dry place for proper storage. To prevent kinking it is usually coiled. To prevent fraying or unravelling, the ends of a rope are bound with twine (whipping), tape, or heat shrink tubing. The ends of plastic fibre ropes are often melted and fused solid.

If a load-bearing rope gets a sharp or sudden jolt or the rope shows signs of deteriorating, it is recommended that the rope be replaced immediately and should be discarded or only used for non-load-bearing tasks.

The average rope life-span is five years. Serious inspection should be given to line after that point.

When preparing for a climb, it is important to stack the rope on the ground or a tarp and check for any "dead-spots".

Avoid stepping on rope, as this might force tiny pieces of rock through the sheath, which can eventually deteriorate the core of the rope.
Ropes may be flemished into coils on deck for safety and presentation/tidiness as shown in the picture.

Line

"Rope" refers to the manufactured material. Once rope is purposely sized, cut, spliced, or simply assigned a function, the result is referred to as a "line", especially in nautical usage. Sail control lines are mainly referred to as sheets(e.g. jibsheet). A halyard

Halyard

In sailing, a halyard or halliard is a line that is used to hoist a sail, a flag or a yard. The term halyard comes from the phrase, 'to haul yards'...

, for example, is a line used to raise and lower a sail

Sail

A sail is any type of surface intended to move a vessel, vehicle or rotor by being placed in a wind—in essence a propulsion wing. Sails are used in sailing.-History of sails:...

, and is typically made of a length of rope with a shackle attached at one end. Other examples include clothesline, chalk line

Chalk line

A chalk line or chalk box is a tool for marking long, straight lines on relatively flat surfaces, much farther than is practical by hand or with a straightedge....

, anchor

Anchor

An anchor is a device, normally made of metal, that is used to connect a vessel to the bed of a body of water to prevent the vessel from drifting due to wind or current. The word derives from Latin ancora, which itself comes from the Greek ἄγκυρα .Anchors can either be temporary or permanent...

line ("rode"), stern line, fishing line

Fishing line

A fishing line is a cord used or made for angling. Important parameters of a fishing line are its length, material, and weight...

, and so on.

Sources

Gaitzsch, W. Antike Korb- und Seilerwaren, Schriften des Limesmuseums Aalen Nr. 38, 1986
Gubser, T. Die bäuerliche Seilerei, G. Krebs AG, Basel, 1965
Hearle, John W. S. & O'Hear & McKenna, N. H. A. Handbook of Fibre Rope Technology, CRC Press, 2004
Lane, Frederic Chapin, 1932. The Rope Factory and Hemp Trade of Venice in the Fifteenth and Sixteenth Centuries, Journal of Economic and Business History, Vol. 4 No. 4 Suppl. (August 1932).
Militzer-Schwenger, L.: Handwerkliche Seilherstellung, Landschaftsverband Westfalen-Lippe, 1992
Nilson, A. Studier i svenskt repslageri, Stockholm, 1961
Pierer, H.A. Universal-Lexikon, Altenburg, 1845
Plymouth Cordage Company, 1931. The Story of Rope; The History and the Modern Development of Rope-Making, Plymouth Cordage Company, North Plymouth, Massachusetts
Sanctuary, Anthony, 1996. Rope, Twine and Net Making, Shire Publications Ltd., Cromwell House, Princes Risborough, Buckinghamshire.
Schubert, Pit. Sicherheit und Risiko in Fels und Eis, Munich, 1998
Smith, Bruce & Padgett, Allen, 1996. On Rope. North American Vertical Rope Techniques, National Speleological Society, Huntsville, Alabama.
Strunk, P.; Abels, J. Das große Abenteuer 2.Teil, Verlag Karl Wenzel, Marburg, 1986
Teeter, Emily, 1987. Techniques and Terminology of Rope-Making in Ancient Egypt, Journal of Egyptian Archaeology, Vol. 73 (1987).
Tyson, William, no date. Rope, a History of the Hard Fibre Cordage Industry in the United Kingdom, Wheatland Journals, Ltd., London

External links

Ropewalk: A Cordage Engineer's Journey Through History History of ropemaking resource and nonprofit documentary film
Watch How Do They Braid Rope?
Zaidimai

The source of this article is wikipedia, the free encyclopedia. The text of this article is licensed under the GFDL.

Construction

Usage

Rock climbing ropes

Aerial rope

History

Laid or twisted rope

Braided rope

Other types

Handling rope

Line

See also

Sources

Further reading

External links