Sheepshank

Sheepshank
An unloaded sheepshank tied in nylon rope.
Category	Shortening
Origin	1627^[1]
Related	Catshank, Dogshank
Releasing	Non-jamming
Typical use	Provides loops, shortens or removes slack from a rope, bypasses a frayed section of rope
Caveat	Spills if not under tension.
ABoK	#1152 - #1154
Instructions

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

The knot has several features which allow a rope to be shortened:

It provides two loops, one at each end of the knot which can be used to pass another rope through
The knot remains somewhat secure under tension; the coarser the rope the more secure it is (see Disadvantages, below)
The knot falls apart easily when tension is removed

Construction methods

A sheepshank knot may be constructed as follows: ...

Pull a section of rope back and lay it alongside the rope, so that the rope forms a Z approximately 20 cm long.
Flatten the Z so that there are 3 sections of rope lying alongside each other, with two U-bends where the rope reverses direction.
At each U-bend, grasp the U-bend in one hand, thus holding two of the rope sections. With the other hand form a small loop in the remaining section and draw it over the U-bend so that the loop forms a half hitch and stays there if the free end of the rope is pulled taut.

Many people draw the small loop over facing the wrong way at least half of the time. Instead, make with the U a half-hitch around the other part, by tucking through, then pull the U straight.

Repeat at the other U-bend.

An alternative method for quickly constructing a sheepshank is as follows:

Create a simple loop in the rope, so that the (left) leading end is on top of the (right) trailing end of the loop.
Repeat this process further down the rope to create 3 total loops that overlap slightly (similar to a venn diagram with three circles).
Reach through the outer two loops and grab either side of the middle loop and pull outward while also keeping the rest of the rope slightly taut.
Once the middle loop is pulled through the outer loops, pull on the free ends of the rope to secure.

The result is a flattened loop which is held at each end by a half hitch. If the sides of the flattened loop are pulled away from each other, the flattened loop ends pull out of the half hitches and the knot falls apart, but if the free ends are pulled taut then the knot remains secure.

Usage

Sheepshank knots are typically used for securing loads to trucks or trailers, and in sailing applications.

Disadvantages

The sheepshank was developed before the use of modern "slippery" synthetic ropes. Constructed from such ropes, under load, it can fail. It is strongly advised that an alternative knot be used.

Variants

Man-o'war sheepshank

The man-o'war sheepshank is a sheepshank knot with a Handcuff knot in the middle. This configuration with the half-hitches formed close to the central knot is used in rope rescue and is called a Fireman's chair knot.

Sheepshank with Marlingspike hitches

This version of the sheepshank is tied by using slipknots instead of half-hitches. It is one of the safest sheepshank variations. ^[2]

Kamikaze knot

The kamikaze knot is a slight variant of the sheepshank. To perform a kamikaze knot, a sheepshank is first constructed. Whilst holding sufficient tension on the sheepshank so it will not slip out, the middle rope is sliced. This allows climbers rappelling down cliff faces to keep most of the rope used for the rappel, by tying the knot at the top, and shaking the rope when they reach the bottom. The shaking disconnects the knot at the top, allowing the longer section of rope to fall, meaning only a small amount of rope is retained by the anchor at the top of the cliff. Thin or slippery rope is unsuitable for such a knot, as it can easily slip, and the knot should not be performed unless desperately needed.

Use

Although certainly not invented by him this variant of the sheepshank knot appeared in an episode of the TV show Man Vs Wild. Bear Grylls uses a modification of this knot by cutting one of the lengths of rope in the knot, while rappelling down an edge during the Ireland episode of Man vs. Wild in order to retrieve his rope at the bottom by severing the middle leg of the sheepshank knot before his descent. He refers to it as a "Kamikaze" knot.

References

↑ knot, hitch, and splice :: Sheepshank. - Britannica Student Encyclopaedia
↑ Ashley, Clifford W. (1944), The Ashley Book of Knots, New York: Doubleday, p. 210

External links

Sheepshank & Variants
Boatsafe.com
Project Gutenberg (September 21, 2004). The Project Gutenberg eBook, Knots, Splices and Rope Work, by A. Hyatt Verrill. Retrieved November 6, 2005. Though the name's a little different, the Sheepshank described above is shown in Figure 79.
Scouting Resources. Sheepshank. Retrieved December 11, 2006. Shows diagrams with accompanying text.
Graumont, Raoul (1945) Handbook of Knots.

Knots

By type

Bends	Adjustable bend Albright special Alpine butterfly bend Ashley's bend Basket weave knot Beer knot Blood knot Carrick bend Double fisherman's knot Fisherman's knot Flemish bend Grief knot Halyard bend Harness bend Heaving line bend Hunter's bend Nail knot One-sided overhand bend Racking bend Sheet bend Shoelace knot Shroud knot Simple Simon under Single carrick bend Surgeon's knot Surgeon's loop Triple fisherman's knot True lover's knot Water knot Zeppelin bend Zeppelin loop

Binding	Boa knot Bottle sling Constrictor knot Corned beef knot Granny knot Ground-line hitch Jamming knot Miller's knot Packer's knot Reef knot Strangle knot Thief knot Transom knot

Climbing	Alpine butterfly knot Autoblock Bachmann knot Beer knot Bowline on a bight Directional figure eight Double anchorman knot Double bowline Farmer's loop Figure-eight knot Figure-eight loop Figure-of-nine loop Friction hitch Klemheist knot Munter hitch Overhand loop Prusik Trident loop Yosemite bowline

Coils	Alpine coil Butterfly coil

Decorative	Carrick mat Chinese button knot Celtic button knot Diamond knot Fiador knot Friendship knot Matthew Walker knot Turk's head knot Wall and crown knot

Fishing (angling)	Angler's loop Arbor knot Bimini twist Blood knot Fisherman's knot Half blood knot Improved clinch knot Knotless knot Nail knot Palomar knot Snell knot Trilene knot Triple fisherman's knot Turle knot Uni knot

Hitches	Adjustable grip hitch Anchor bend Axle hitch Bachmann knot Bale sling hitch Barrel hitch Becket hitch Blackwall hitch Blake's hitch Boom hitch Buntline hitch Cat's paw Clove hitch Cow hitch Double overhand noose Falconer's knot Farrimond friction hitch Friction hitch Garda hitch Gripping Sailor's hitch Ground-line hitch Half hitch Halter hitch Highpoint hitch Highwayman's hitch Hitching tie Icicle hitch Improved clinch knot Killick hitch Knute hitch Lobster buoy hitch Marlinespike hitch Munter hitch Ossel hitch Pile hitch Snuggle hitch Swing hitch Taut-line hitch Timber hitch

Loop	Angler's loop Artillery loop Bale sling hitch Bowline Bumper knot Carrick bend loop Cowboy bowline Diamond knot Double bowline Dropper loop Eskimo bowline Fiador knot Fireman's chair knot Friendship knot loop Halter hitch Handcuff knot Honda knot Jury mast knot Overhand loop Portuguese bowline Rigid double splayed loop in the bight Slippery eight loop Span loop Spanish bowline Tom fool's knot Trident loop Triple bowline Triple crown knot Water bowline Yosemite bowline Zeppelin loop

Running (slip)	Hangman's knot Running bowline Running highwayman's hitch Slip knot Tarbuck knot

Shanks	Catshank Dogshank Sheepshank

Stopper	Ashley's stopper knot Button knot Double overhand knot Monkey's fist Overhand knot Stevedore knot

Whipping	Common whipping Overhand knot with draw-loop Portuguese whipping Sailmaker's whipping West Country whipping

Lists of knots
Related topics

Lists of knots	Bends Bindings Decorative knots Hitches (friction) Macramé Mathematical

Related topics	Chinese knotting International Guild of Knot Tyers Lashing Rope splicing Seizing

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