Eskimo bowline

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Eskimo bowline
EskimoBowline.jpg
NamesEskimo bowline, Sitka loop, anti-bowline, Cossack knot, Kalmyk loop
Category Loop
Origin Ancient
Related bowline, sheet bend, double bowline, water bowline, spanish bowline, triple bowline, bowline on a bight, running bowline, poldo tackle, cowboy bowline
Releasing Non-jamming
Typical usePlacing a loop which will be stretched wide open under load in the end of a rope

The Eskimo bowline, reverse bowline, or 'anti-bowline' is in a class of knots known as 'eye knots' (some prefer to use the term 'loop knots'). The eye is formed in the end of the rope to permit attachments/connections. The simple (ABoK #1010) bowline is also an 'eye knot'. In the simple bowline, the collar component forms around the 'standing part'. In contrast, the collar component of an anti-bowline forms around the outgoing eye-leg.

Eskimo bowline based on the method described by Geoffrey Budworth in The Illustrated Encyclopedia of Knots. The tightened knot on the right takes on a trefoil crown shape. Eskimo-bowline.jpg
Eskimo bowline based on the method described by Geoffrey Budworth in The Illustrated Encyclopedia of Knots. The tightened knot on the right takes on a trefoil crown shape.

The Eskimo bowline is best used in applications where the eye will be subject to a transverse loading profile (aka ring loading). In loading profiles where the eye is axially loaded in alignment with the SPart (Standing Part), a bowline is preferred. NOTE: In a transverse loading profile, the SPart is isolated from load.

The structure of the knot was not identified by Clifford Ashley (in 1944). All of the maneuvers to tie this knot are generally in the opposite (or 'anti' direction) relative to the bowline.

Dan Lehman[ who? ] regards the general, bowline-like structure as an 'anti-bowline' in the sense that tying maneuvers are performed in a general 'anti' direction relative to the simple #1010 Bowline. After forming the 'nipping loop' (which can be formed as 'S' or 'Z' chirality) the working end is fed through that loop from the same side as the outgoing eye leg. This is opposite (or 'anti') direction relative to the simple (#1010) Bowline. When the eye of this knot is loaded in a transverse direction, the knot effectively mimics a sheet bend. (The image above with red rope would result in an ends-opposite (and inferior) sheet bend; the version shown on the right side would give a same-side sheet bend (ABoK #1431). When the eye of a simple Bowline is subject to a transverse loading profile, it mimics the inferior version of the Lapp bend, and so can slip and untie; the wrongly demeaned "left-handed"/"cowboy" bowline becomes the proper Lapp bend, and should hold.)[ citation needed ]. Note: Some knot theorists use the term 'ring loading' in lieu of transverse loading.

Sheet bend Schotstek rechts.jpg
Sheet bend

The so called 'Eskimo' Bowline has also been known as a 'Boas Bowline' and a Cossack knot - all of these names referring to the same structure. A slipped version of this knot is called Kalmyk loop. [2] [3] Interestingly, anti Bowlines can be made 'TIB' (Tiable In the Bight) by slipping the tail. However, it will not be 'EEL' (Either End Loadable).

See also

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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.

Bowline Simple knot used to form a fixed loop at the end of a rope

The #1010 Simple Bowline is an ancient and simple knot used to form a fixed eye at the end of a line. It has the virtues of being both easy to tie and untie; most notably, it is easy to untie after being subjected to a heavy load. The Simple Bowline is sometimes referred to as King of the knots because of its resistance to jamming and simple, easy to remember structure. Along with the sheet bend and the clove hitch, the simple Bowline is often considered one of the most essential knots.

Sheepshank Type of knot

A shank is a type of knot that is used to shorten a rope or take up slack, such as the sheepshank. The sheepshank knot is not stable. It will fall apart under too much load or too little load.

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.

Truckers hitch

The trucker's hitch is a compound knot commonly used for securing loads on trucks or trailers. This general arrangement, using loops and turns in the rope itself to form a crude block and tackle, has long been used to tension lines and is known by multiple names. Knot author Geoffrey Budworth claims the knot can be traced back to the days when carters and hawkers used horse-drawn conveyances to move their wares from place to place.

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.

Zeppelin bend

A Zeppelin bend is an end-to-end joining knot formed by two symmetrically interlinked overhand knots. It is stable, secure, and highly resistant to jamming. It is also resistant to the effects of slack shaking and cyclic loading.

Sheet bend

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

Cowboy bowline

The cowboy bowline is a variation of the bowline loop knot.

Bowline on a bight Knot that makes a pair of fixed-size loops in the middle of a rope

The Bowline on a bight is a knot which makes a pair of fixed-size loops in the middle of a rope. Its advantage is that it is reasonably easy to untie after being exposed to load. This knot can replace the figure-eight loop knot when tying into a climbing harness. It is one of the two tie-in knots that are being taught by the German Alpine Club (DAV), generally being considered secure.

Yosemite bowline Loop knot often perceived as having better security than a bowline

A Yosemite bowline is a loop knot often perceived as having better security than a bowline. It has been pointed out that if the knot is not dressed correctly, it can potentially collapse into a noose, however testing reveals this alternative configuration to be strong and safe as a climbing tie-in.

Bight (knot)

In knot tying, a bight is a curved section or slack part between the two ends of a rope, string, or yarn. A knot that can be tied using only the bight of a rope, without access to the ends, is described as in the bight. The term "bight" is also used in a more specific way when describing Turk's head knots, indicating how many repetitions of braiding are made in the circuit of a given knot.

Zeppelin loop Form of loop knot

A zeppelin eye knot, is a secure, jam resistant fixed size loop knot based on the zeppelin bend. It is one of the few eye knots suitable for bungee. It is also special in its ease of untying.

Harness bend

The harness knot is a general purpose bend knot used to join two ropes together. The knot can be tied under tension and will not capsize.

Karash double loop

Karash double loop is a common name for a knot forming two loops. This knot has been a known variant of the Bowline on a bight per the International Guild of Knot Tyers, referred to as bowline twist or twisted collar bowline on a bight. The knot is also referred to as nœud de fusion in French references and sometimes called Fusion knot in English.

Carrick bend loop

A carrick bend loop or carrick loop is a knot used to make a reliable and stable loop at the end of a rope formed by the tail turned around and attached to the main part using a carrick bend.

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."

Kalmyk loop

The Kalmyk Loop is a fixed loop still largely unused in the West, but common in Russia and often used instead of the bowline.

References

  1. Budworth, Geoffrey (2002). The Illustrated Encyclopedia of Knots. Lyons Press. ISBN   978-1585746262.
  2. Video on YouTube Tying video for Kalmyk loop
  3. Video on YouTube Tying video for Kalmyk loop