Sheepshank (shortening a rope)

In the sheepshank the rope is laid in an S-shape into three parallel parts. This creates a bight at each end. Then, in the standing part next to each bight, you make a small loop – a half hitch – and drop it over the bight. When you pull on both ends, the hitches squeeze the bights together and the rope stays shortened.

This construction holds only because of the tension itself. Nothing is tucked through anything else; everything just lies on top. As soon as the tension eases, the rope flaps or is moved sideways, the hitches can slide off the bights. That is why newer knot books point out explicitly that an unsecured sheepshank is unreliable.

A correctly tied sheepshank looks like a long bundle of three parallel lengths of rope, with a small loop sitting snugly around a bight at each end. The bights should stick well out of the loops; if they are too short, they slip out at the slightest movement.

Dress the three parts so they lie parallel and untwisted, then pull evenly on both ends until the hitches sit firmly on the bights. For more reliability, push a short stick through each bight as a toggle, outside the hitch, or seize the bights to the rope with thin cord. Then the hitches cannot slide off so easily.

The sheepshank can help to shorten an overlong rope temporarily, for example a washing line or a line that is constantly under tension. It is also a good learning knot, because it shows very clearly how bights and hitches work together – and why a knot can fail without tension.

It is unsuitable for lines without constant tension, for lines that flap and for anything that must not fall. The old claim that it can safely bypass a damaged section of rope holds at most for light, non-critical loads. A damaged rope does not become sound again this way. If a line only needs to be shorter for a while, the chain sinnet is the more reliable choice.

A sheepshank can come apart as soon as tension eases or the rope is moved. Use it only for non-critical purposes and check it regularly. Typical mistakes are: leaving the knot without tension, making the bights too short and using it to bypass a damaged section under important load.

A rope with a damaged section should be retired from load-bearing use or cut at that point, leaving two shorter, intact pieces. Life-safety use of knots only after proper training with certified equipment – and even then the sheepshank is not intended for it.

The sheepshank has been taught in scouting and seamanship books for generations and is therefore very well known. But being well known is not the same as being reliable: this knot is a good example of why old advice should be checked. Ashley already described secured variants because the basic form falls apart so easily.

To practise, tie it in a line between two chair backs. Tension the line, then let it go slack and jiggle it a little. You will see at once how quickly it falls apart. Repeat the whole thing with two sticks as toggles – and finally compare it with the chain sinnet.