NZSS Caving Knots
A wide variety of knots are possible to use when caving. Some have advantages over others. Some can be used to impress fellow cavers of your knowledge of knots and rigging skills. However, if you are like the majority of cavers and find it difficult to remember how to tie the multitude of possible knots, then you can get by with learning only two: the figure-8 and the tape knot. These two knots can be used to rig tapes, belay points, rebelays, rope joining and waist belays.
Some knots can be tied on a bight. A bight is simply a loose loop or doubled-over rope i.e. the knot is tied with a double thickness in the middle of a rope, rather than with a single thickness at one end.
This is an extremely useful knot to learn. If you only learn a few knots, then this is a must. If it is tied on a bight, the loop formed can be used to tie into belays or rebelays. If it is tied on a single thickness of rope, the rope end can be followed back through the knot, allowing you to include a belay point in the loop directly. If another rope end is followed back through the knot, two ropes can be joined.
The figure-8 knot is one if the stronger knots used in caving but can become difficult to untie after being directly loaded for a period of time c.f. the butterfly knot. If the knot is loaded between the rope ends, the knot can deform.The knot can be modified to produce two adjustable loops, ideal for equalizing loads on a Y-hang (see diagram). Simply form a large loop when tying the knot on a bight. Feed the end of the loop back through the first part of the knot , then loop it back over the two loops thus formed and pull the slack out using the two loops formed. Note that if one loop is damaged, the other is directly affected also.
This is probably the strongest knot used in caving in that it weakens the rope least c.f. other knots. It is tied in similar fashion to a figure-8 on a bight but the bight is carried around an extra half turn before being passed through the loop. It is used in similar situations as a figure-8 but tends to be less popular since:
It is probably a wise idea to use this knot with thinner ropes rather than the figure-8.
This is an easily tied knot used to form a loop in the middle of a rope. Although not as strong as a figure-8, it is often used to achieve a Y-hang (along with a figure-8 on one of the Y ends) or to tie into a rebelay. It does not tend to jam as much as a figure-8 when loaded directly. It can also be loaded in all directions.
An extremely simple knot to tie, the clove hitch is a versatile knot. It can be loaded from either of the rope ends. It is sometimes useful to use the clove hitch when wishing to keep a tape sling in a particular position on a bollard or spike.
Although not a knot, the italian hitch on a krab is useful for belaying if no other devices are available. At a pinch, you can abseil with an italian hitch on a krab but it is rather hard on the rope. The italian hitch can be reversed by pulling on the other ends of the rope and reversing the "hitch".
This knot is used to join ropes. It tends to be bulky and difficult to undo but this can be eased somewhat by tying a reef knot between the two ropes first, then using the rope ends to tie the double fishermans knot (and make and even bulkier knot!).When it is tied normally, the two ends of the knot pull together closely. If not, reverse the direction of turning of one side of the knot while it. An alternative knot to use to join two ropes together is the figure-8.
The bowline is an easy knot of mis-tie. It can be used to loop around a thread to use as a belay, or to tie around the waist of a person to be belayed. It has a tendency to work loose so it is advisable to tie a half-hitch with the rope end.
The bowline can be tied on a bight to give two adjustable loops for a Y-hang (see diagram).
This is the simplest of knots to tie and is the best to use to tie tapes. The knot is simply an overhand knot in a tape. If the knot is tied on one end of a tape, the other end can be fed back through the knot to form a loop of tape. Arrange the knot so the tape lies flat in the knot. If the knot is tied in a bight, a small loop can be formed on the end of a tape. If the other end is knotted the same, the tape can be fed through a thread belay and joined with a krab. The advantage being that this can be derigged without the knots having to be undone in a cave.