Here’s part two of the abseil knot section of my book Down. It would be great if people could share this as widely as possible.
The following knots are all high strength and although less effective in rappel than the OOB, are worth learning and understanding.
Single Fisherman’s (Fig 159)
A very simple and compact knot, that although looking weak, is actually very strong. Nevertheless, such a simple knot does not inspire confidence and can become welded together, so the Double Fisherman’s is generally used instead.
Double Fisherman’s (Fig 160)
A little harder to tie correctly with the aim for each side to mirror the other. This is easier to untie and is also very strong and stable, and the old school standard method.
Ring bend (Fig 161)
Tie a water knot 30 cm along one rope, then rethread the other rope through it to create a compact but strong knot, but again, one that’s easily welded shut when weighted.
Figure-Eight bend (Flemish) (Fig 162)
One of the best inline knots, being easy to tie, strong and not too hard to untie. To tie, just tie a Figure-Eight in one strand, then rethread the other strand through it, leaving a 30 cm tail.
Reef Knot with stoppers (Fig 163)
For years, this was the standard abseil knot, the reef knot being high strength and the easiest of all knots to untie. The entire load is born by the reef knot, and the stopper knots are simply there to ease the mind, very often loosening and coming apart in action. For the modern climber, this combo is just too big and bulky.
Alpine Butterfly (Fig 164)
The king of high loading and re-belays, this is often overlooked for abseil ropes, but it’s easily done. To join, it’s easiest to start by tying two strands together with an Overhand or Fisherman’s, then wrap the rope around your palm three times, having the abseil knot in the middle. Now move the outside (fingers) strand to the inside (wrist), then the joined strands, but pull it under and through the other two strands. Tighten the knot and remove the Overhand if not required, leaving 30 cm tails.
Zeppelin bend (Fig 165)
Designed to hold airships in place yet still be easily untied, this is a very effective knot for high loads, but is rarely used as its specialisation means only knot nerds know how to tie it, and I’d advise just to learn the Alpine Butterfly inside and out.
Miss-tied knots and half tied knots can be deadly, as well as leaving too short a tail, so being able to focus, not being distracted, and knowing what the hell you are doing, remains the only way to avoid such terminal errors. When tying knots, have your partner check it – like they would your parachute – and you check your partners. Remember, people make stupid mistakes.
The deadly offset Figure-Eight bend (Fig 166)
This is a very curious knot on many levels. There are many reputable publications and organisations that still advocate the use of the offset Figure-Eight, and climbers persist with it on the assumption that it has to be stronger than a very weak looking Offset Overhand Bend. There are even tests that show they’re strong to use, but in reality, it’s deadly.
When you do a search of rappel accidents, you will find several that involve Figure-Eights coming undone. Accidents - like most accidents - are compounded by several factors, such as knots that were sloppily tied, wet ropes and tails that were too short.
Such things can easily be put down to pilot error. But when you have such an accident happen to a highly experienced friend, who rapped on an offset Figure-Eight bend in a rainstorm, only for the knot to come apart as his partner set off down, you take it as seriously.
The problem with the offset Figure-Eight is that it rolls at a lower load than an Overhand, and due to it holding a greater length of rope, rolls much further. This rolling threshold is also lowered by wet, frozen or new ropes, with a dry coating or a super tight sheath. The ability to recreate real-life loads in a lab is limited, as there are so many factors at play in such accidents; so although on paper the offset Figure-Eight should be a valid knot to use, it is neither as strong or stable as an Offset Overhand Bend or forgiving and so should never be used (and tell people you see still using it).