Figure-eight knot

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This article is about the knot. For the mathematical concept, see Figure-eight knot (mathematics). For other uses, see Figure 8.
Figure-eight knot
Figure-eight knot.svg
Names Figure-eight knot, figure-of-eight knot, Savoy knot, Flemish knot, double stopper
Category Stopper
Efficiency 80%
Origin Ancient
Related Stevedore knot, figure-eight loop, figure-eight follow through, directional figure eight
Releasing Jamming
Typical use General-purpose stopper knot. Replaces the common overhand knot in many uses.
ABoK #420 #570
Conway Notation 2 2
A/B notation 41
Instructions [1]

The figure-eight knot is a type of knot. It is very important in both sailing and rock climbing as a method of stopping ropes from running out of retaining devices. Like the overhand knot, which will jam under strain, often requiring the rope to be cut, the figure of eight will also jam, but is usually more easily undone than the overhand knot.

Different types of figure-eight knots[edit]

Figure-eight loop[edit]

The figure-eight loop is used like an overhand loop knot. This type of knot can be used in prusik climbing when used in conjunction with a climbing harness, a climbing rope, and locking carabiner designed for climbing, to ascend or descend with minimal equipment and effort.

Figure-eight splice knot[edit]

Main article: Flemish bend

Figure-eight splice knot is used to quickly and effectively "splice" together two ropes, not necessarily of equal diameter. This knot is tied starting with a loose figure-eight knot on one rope (the larger-diameter one if unequal), and threading of the other rope's running end through the first figure eight, starting at the first figure-eight's running end and paralleling the path of the first rope through the figure eight until the second's ropes running end lies parallel against first's standing end. The result is two figure-eight knots, each partly inside the other and tightening its hold on the other when they are pulled in opposite directions. This can be a permanent or temporary splice. While it precludes the ropes' slipping relative to each other, it is a typical knot in having less strength than the straight ropes.

In heraldry, this knot is known as Savoy knot.

Stein knot[edit]

Stein knot

The stein knot (aka stone knot) is a variation of the figure-eight knot. It is used to secure a rope that is already passed around a post or through a ring. It is quick and easy to tie and untie. It is a device rigging rather than a true knot.

In canyoneering, it is used to isolate rope strands to allow one person to rappel while another is getting on the rappel, or allow rappellers the option of using a single or a double rope. It is also used to make baskets

See also[edit]

References[edit]

Further reading[edit]

  • Adams, Colin C. (1994). The knot book: an elementary introduction to the mathematical theory of knots. W. H. Freeman.