Bight (knot)
In knot tying, a bight is a curved section or slack part between the two ends of a rope, string or yarn.[1] "Any section of line that is bent into a U-shape is a bight."[2] An open loop is a curve in a rope narrower than a bight but with separated ends. [3] The term 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.[4]
Slipped knot
In order to make a slipped knot (also slipped loop and quick release knot), a bight must be passed, rather than the end. This slipped form of the knot is more easily untied. The traditional bow knot used for tying shoelaces is simply a reef knot with the final overhand knot made with two bights instead of the ends. Similarly, a slippery hitch is a slipped clove hitch.
In the bight
The phrase in the bight (or on a bight) means a bight of line is itself being used to make a knot. Specifically this means that the knot can be formed without access to the ends of the rope.[5] This can be an important property for knots to be used in situations where the ends of the rope are inaccessible, such as forming a fixed loop in the middle of a long climbing rope.
Many knots normally tied with an end also have a form which is tied in the bight, for instance the bowline and the bowline on a bight. In other cases a knot being tied in the bight is a matter of the method of tying rather than a difference in the completed form of the knot. For example the clove hitch can be made in the bight if it is being slipped over the end of a post but not if being cast onto a closed ring, which requires access to an end of the rope. Other knots, such as the overhand knot, cannot be tied in the bight without changing their final form.
Examples
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The blue rope (right) is half-hitched through and around a bight of the red rope (left) in this Sheet bend.
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The final tuck of this Slipped buntline hitch is made with a bight rather than the end, making it easier to release after tightening.
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In the tying of a marlinespike hitch, a bight of the standing part is snagged through the loop.
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The bights, in the case of this 3-lead 10-bight Turk's head knot, are the scallops along the perimeter of the knot.
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The Alpine butterfly knot is a climbing knot which is tied in the bight and forms a reliable fixed loop.
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The Bowline on a bight forms two fixed loops in the middle of a rope.
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An Overhand knot tied in the bight results in an Overhand loop.
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A figure-eight knot tied in the bight results in a figure-eight loop.
References
- ↑ Clifford W. Ashley, The Ashley Book of Knots (New York: Doubleday, 1944), 597. ISBN 9780385040259.
- ↑ Budworth, Geoffrey (2002). The Illustrated Encyclopedia of Knots, p.18. ISBN 9781585746262.
- ↑ Ashley (1944), 13.
- ↑ Ashley (1944), 232.
- ↑ Ashley (1944), 207.
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