Lashing (ropework)

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Bamboo scaffolding secured with lashings in Kowloon. Temple St. bamboo scaffolding 2.JPG
Bamboo scaffolding secured with lashings in Kowloon.

A lashing is an arrangement of rope, wire, or webbing with linking device used to secure and fasten two or more items together in a somewhat rigid manner. Lashings are most commonly applied to timber poles, and are commonly associated with cargo, containerisation, the Scouting movement, and sailors.

Contents

This word usage derives from using whipcord to tie things together.[ citation needed ]

It has been imagined that the first lashing made by humans was wrapping a few strips of bark around a stone to hold it to a tree branch to make an ax to hunt and build with.[ citation needed ] In modern times, the same methods are used, but strips of bark and vines have been replaced with natural and synthetic fiber ropes. Scouts and campers use lashings to build camp gadgets and improve their campsites for comfort and convenience, including the building of rafts for transport and competitive events. Lashings are also used in pioneering, the art of creating structures such as bridges and towers, using ropes and wooden spars.

There are still areas in the world where lashing spars (or poles) is the basic means of building.[ citation needed ]

A square lashing binding a wooden spar to a tree trunk Square lashing with piece of wood.JPG
A square lashing binding a wooden spar to a tree trunk

Types

Square lashing

Square lashing is a type of lashing used to bind spars together, at right angles to one another. There are different types, but all consist of a series of wraps around the spars, and frapping around the line running between the spars.

Diagonal lashing

Diagonal lashing is a type of lashing used to bind spars or poles together, to prevent racking. It gets its name from the fact that the wrapping turns cross the poles diagonally and is used to spring poles together where they do not touch as in the X-brace of a trestle. [1]

Shear lashing

Shear lashing (two-spar shear lashing) also spelled "sheer lashing" is used for lashing together two parallel spars which will be opened out of the parallel to form sheer legs as in the formation of an A-frame. The clove hitch is tied around one leg only and frapping turns are taken between the poles. [2]

Round lashing

The round lashing is most frequently used to join two poles together to extend their length. Typically, two lashings are used a reasonable distance apart for extra strength. In the simple version, a clove hitch is tied around both poles and there are no frapping turns. [3]

Tripod lashing

The tripod lashing (also known as gyn lashing, of eight lashing, and three-spar shear lashing) is used to join three spars together to form a tripod.

See also

Related Research Articles

Knot Method of fastening or securing linear material

A knot is an intentional complication in cordage which may be practical or decorative, or both. Practical knots are classified by function, including hitches, bends, loop knots, and splices: a hitch fastens a rope to another object; a bend fastens two ends of a rope to each another; a loop knot is any knot creating a loop, and splice denotes any multi-strand knot, including bends and loops. A knot may also refer, in the strictest sense, to a stopper or knob at the end of a rope to keep that end from slipping through a grommet or eye. Knots have excited interest since ancient times for their practical uses, as well as their topological intricacy, studied in the area of mathematics known as knot theory.

Constrictor knot binding knot

The constrictor knot is one of the most effective binding knots. Simple and secure, it is a harsh knot that can be difficult or impossible to untie once tightened. It is made similarly to a clove hitch but with one end passed under the other, forming an overhand knot under a riding turn. The double constrictor knot is an even more robust variation that features two riding turns.

Clove hitch

The clove hitch is a type of knot. Along with the bowline and the sheet bend, it is often considered one of the most important knots. A clove hitch is two successive half-hitches around an object. It is most effectively used as a crossing knot. It can be used as a binding knot, but is not particularly secure in that role. A clove hitch made around the rope's own standing part is known as either two half-hitches or buntline hitch, depending on whether the turns of the clove hitch progress away from or towards the hitched object.

Although the name clove hitch is given by Falconer in his Dictionary of 1769, the knot is much older, having been tied in ratlines at least as early as the first quarter of the sixteenth century. This is shown in early sculpture and paintings. A round turn is taken with the ratline and then a hitch is added below. The forward end is always the first to be made fast.

The difference between two half hitches and the clove hitch is that the former, after a single turn around a spar, is made fast around its own standing part, while the latter is tied directly around the spar.

A whipping knot or whipping is a binding of marline twine or whipcord around the end of a rope to prevent its natural tendency to fray.

Taut-line hitch

The taut-line hitch is an adjustable loop knot for use on lines under tension. It is useful when the length of a line will need to be periodically adjusted in order to maintain tension. It is made by tying a rolling hitch around the standing part after passing around an anchor object. Tension is maintained by sliding the hitch to adjust the size of the loop, thus changing the effective length of the standing part without retying the knot.

Pioneering (scouting)

Pioneering is the art of using ropes and wooden spars joined by lashings and knots to create a structure. Pioneering can be used for constructing small items such as camp gadgets up to larger structures such as bridges and towers. These may be recreational, decorative, or functional.

Sheet bend

The sheet bend is a bend. It is practical for joining lines of different diameter or rigidity.

Half hitch

The half hitch is a simple overhand knot, where the working end of a line is brought over and under the standing part. Insecure on its own, it is a valuable component of a wide variety of useful and reliable hitches, bends, and knots.

Rolling hitch

The rolling hitch is a knot used to attach a rope to a rod, pole, or another rope. A simple friction hitch, it is used for lengthwise pull along an object rather than at right angles. The rolling hitch is designed to resist lengthwise movement for only a single direction of pull.

Scuttlebutt in slang usage means rumor or gossip, deriving from the nautical term for the cask used to serve water.

Two half-hitches

Two half-hitches is a type of knot, specifically a binding knot or hitch knot. One variety consists of an overhand knot tied around a post, followed by a half-hitch. This knot is less often referred to as a clove hitch over itself, double half-hitch, or full-hitch.

Two half hitches is the commonest of all hitches for mooring in particular and also for general utility. Steel gives the name in 1794. The difference between two half hitches and the clove hitch is that the former, after a single turn around a spar, is made fast around its own standing part, while the latter is tied directly around the spar.

Seizing

Seizings are a type of stopping knots used to semi-permanently bind together two ropes, two parts of the same rope, or rope and another object. Akin to lashings, they use string or small-stuff to produce friction and leverage to immobilize larger ropes. Seizings are not recommended for heavy loads for critical use as strain reduces the diameter of the main rope and can permit slippage even with proper construction. According to The Ashley Book of Knots, "A seizing holds several objects together." The other type of stopping knots are whipping knots.

A throat seizing is a seized round turn. It is used when turning in deadeyes, and has riding turns but no crossing turns. The end of the stay or shroud should first be stopped around the deadeye.

A gyn is an improvised three legged lifting device used on sailing ships. It provides more stability than a derrick or sheers, and requires no rigging for support. Without additional support, however, it can only be used for lifting things directly up and down. Gyns may also be used to support either end of a ropeway.

Shear legs

Shear legs, also known as sheers, shears, or sheer legs, are a form of two-legged lifting device. Shear legs may be permanent, formed of a solid A-frame and supports, as commonly seen on land and the floating sheerleg, or temporary, as aboard a vessel lacking a fixed crane or derrick.

Snuggle hitch

The snuggle hitch is a modification of the clove hitch, and is stronger and more secure. Owen K. Nuttall of the International Guild of Knot Tyers came up with this unique hitch, and it was first documented in the Guild's Knotting Matters magazine issue of January, 1987. Generally, hitches are used to attach a line to another rope or spar, pole, etc., and are usually temporary. Thus, they should be relatively easy to untie.

Pipe hitch

A pipe hitch is a hitch-type knot used to secure smooth cylindrical objects, such as pipes, poles, beams, or spars. According to The Ashley Book of Knots, a pipe hitch is "used to lower a pipe or hoist one" and as "another method of tying to a rectangular timber."

Reef knot Type of knot

The reef knot, or square knot, is an ancient and simple binding knot used to secure a rope or line around an object. It is sometimes also referred to as a Hercules knot. The knot is formed by tying a left-handed overhand knot and then a right-handed overhand knot, or vice versa. A common mnemonic for this procedure is "right over left; left over right", which is often appended with the rhyming suffix "... makes a knot both tidy and tight". Two consecutive overhands of the same handedness will make a granny knot. The working ends of the reef knot must emerge both at the top or both at the bottom, otherwise a thief knot results.

The reef knot or square knot consists of two half knots, one left and one right, one being tied on top of the other, and either being tied first...The reef knot is unique in that it may be tied and tightened with both ends. It is universally used for parcels, rolls and bundles. At sea it is always employed in reefing and furling sails and stopping clothes for drying. But under no circumstances should it ever be tied as a bend, for if tied with two ends of unequal size, or if one end is stiffer or smoother than the other, the knot is almost bound to spill. Except for its true purpose of binding it is a knot to be shunned.

Swing hitch

Swing hitch is a way to tie a swing rope to a branch or other horizontal beam. Ashley describes it in ABOK as "... firm, strong, secure, and easily untied once the load has been removed."

References

  1. Green, Larry (14 December 2014). "Traditional Diagonal Lashing". scoutpioneering.com.
  2. Green, Larry (14 October 2013). "The Somewhat Ambiguous Shear Lashing".
  3. Green, Larry (27 January 2014). "Four Different Lashings to Extend the Length of a Spar".