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A Few Good Knots

Phil Benchoff
November 16, 2002

Subsections


Rope is simple, ubiquitous, ancient. A creature of tension, it exists to be stretched between opposing forces. It is a highly evolved tool which, in its myriad sizes, materials, and constructions, can meet every sort of rigging need. Limitations are likely to be on the part of the user; it is for us to develop skill appropriate to the tool. [Tos98, p 1]

Only fourteen knots are required for your membership test. They have been selected to provide a common set of tools for all members, and these tools will be sufficient for most rigging. You should be able to tie all of these knots as easily as you tie your shoes; lives may depend on your ability to tie them when you're tired, hungry, cold, confused, and in darkness. Learn, practice, and master these knots.

Learning to tie knots from printed material is not easy; get personal instruction from a member with vertical experience if you can. Animated images on the Internet are also helpful.

Terms and Functions

A few terms are used to describe knots and rigging.

  • The working end of the rope is what you tie to the anchor.
  • The standing line is the part of the rope between the anchor and load. It is the part you rappel or climb.
  • The running end or free end is the end of the rope that is not attached to the anchor. It is the part of the rope you are not supposed to rappel off.
  • A bight is formed when the rope is doubled back but does not cross itself.
  • A loop is formed when the rope is doubled back and crosses itself.
  • A knot or true knot is formed when a rope is tied to itself. Fixed loops, mid-line loops, and stopper knots are true knots.
  • A hitch is used to fasten a rope some object or another rope. The rope or object you are hitching to is not part of the knot; a hitch will fall apart if the rope or object is removed.
  • A bend is used to fasten one rope to another.
  • Knots, hitches, and bends are all ties, but it is usual to call all of them knots.

Selection and Characteristics

Here are some things to consider when selecting which knot you will use for a particular job.
  • Is the knot suitable for the type of material you are using? Different types of material may require different knots. Knots that work in webbing may not work in rope. Many of the knots seen in typical knot references do not work well in the stiff and slick synthetic ropes used for caving.
  • How secure is the knot? Security of a knot refers to how well the knot maintains its shape under load. Many knots that are very secure under constant tension will fail in situations where the rigging is alternately loaded and unloaded. An additional overhand knot is often added to secure the primary knot.
  • How strong is the knot? Bending or twisting a rope reduces its strength. Most sources will give figures of 20-50% strength reduction with a typical knot.
  • Is the knot suitable for the load?
  • How likely is the knot to capsize? Capsizing refers to a failure of a knot where its structure changes under load. The best example of this is what happens when the free end of a square knot is pulled.
  • Does the knot jam? Some knots will jam after heavy loading. The difficulty of removing a particular knot may require the use of tools that damage the rope (requiring the damaged section of rope to be discarded).
  • Can the knot be tied under tension?
  • How compact is the knot?
  • How much rope does the knot require?
  • How hard is it to examine the knot and tell if it is tied correctly? It is important that each person who will use some rigging be able to examine it and confirm that it is rigged correctly.

Tying a Knot

A knot is never nearly right; it is either exactly right or it is hopelessly wrong, one or the other; there is nothing in between. This is not the impossibly high standard of the idealist, it is a mere fact for the realist to face. In a knot of eight crossings, which is about the average-size knot, there are 256 "over-and-under" arrangements possible. Make only one change in this "over-and-under" sequence and either an entirely different knot is made or no knot at all may result. -- [Ash44, #77,78,79]

Tying a knot is more complicated than just arranging the rope like one of the illustrations. Here are some steps to follow.

  • Select knot that is suitable for the job and material.
  • Tie the knot.
  • Dress the knot by arranging all parts of the knot in the correct orientation. When tying a knot with webbing, try to keep the webbing as flat (not twisted) as possible. Re-traced (re-threaded) knots (like the re-traced figure-8) also require special care.
  • Set the knot by taking up the slack on all parts of the knot. Be sure to maintain the correct orientation.
  • Secure (backoff, backup) with an overhand loop, double overhand loop, or specialized method. Knots used to secure another knot should be as close as possible to the main knot and oriented to fit tightly against it. (Sometimes the backoff is part of the knot and must be done prior to setting, e.g. bowline with Yosemite finish.)
  • Inspect the finished knot and securing knot. Do not leave unsecured or incorrect knots in the rigging. It may not be obvious to others that it is not ready to use.

Once you learn to identify and tie the required knots, spend some time learning different techniques of tying them. The references section of this document lists several good places to learn specialized techniques that will help you tie the knots quickly and correctly in a variety of situations.

Beyond Knots

Knots are only one of the tools required for a rigging project. Mastery of knots is similar to knowing how to start your car - a fundamental skill, but only a part of the skills required. To have a safe vertical trip, the group will require additional knowledge and/or experience in the following areas:

  • Rope care and inspection
  • Selection of rig points
  • Equipment (harnesses, descenders ascenders, pads, etc.)
  • Climbing and belay calls
  • Hauling and pulley systems
  • Everything you need for a safe horizontal trip

Required Knots

Little is known about the mechanics of knots, and friction itself is still a scientific mystery. Under the circumstances, it behooves the laymen to speak skeptically rather than dogmatically about why knots behave the way they do. [Day86, p 16]

Notes on the Illustrations

To provide the clearest information for learning to recognize and tie the selected knots, some of the illustrations show knots that are not complete or are not quite in the form that they should be used. In particular, knots are shown before being set, without the required backoff, or with tails and loops of incorrect size.

Overhand Knot

The overhand knot (or thumb knot) is the simplest of all knots. Its most common use is to secure (or backup) a more complicated knot. Of the fourteen required knots, four are based on the overhand knot (overhand knot, water knot, square knot, double fisherman's bend), and four are secured with overhand knots (bowline, mountaineering bowline, bowline on a coil, and helical).

  • When used to secure a knot, two forms of the overhand knot are possible: the inside form and the outside form. The inside form is preferred since it is more compact and symmetric, and the two ropes lay parallel to each other.
  • There are two possible orientations for the inside form of the overhand knot depending on which way the the turn is taken around the standing part. Viewed from the side, the knots slope in opposite directions. Choose the one that puts the backup knot closest to the main knot.
  • Two turns can be taken around the standing rope to form the double overhand knot.
  • The overhand knot can be used as a stopper knot (e.g. to keep a line from running through an opening), but it is prone to jamming. A figure-8 is a better choice.
  • When tied with the ends of two ropes, this knot is more properly called a half knot.
The Overhand Knot
Overhand knot Overhand knot (inside) Overhand knot (outside) Double overhand Double overhand
Overhand knot Overhand knot (inside) Overhand knot (outside) Double overhand knot Double overhand knot

Animated overhand knot

Animated double overhand

Water Knot

The water knot (or ring bend) is most often used to bend two lengths of webbing together. It is easily tied by tying an overhand knot in the end of one length of webbing and then re-tracing the knot with the end of the other length of webbing. This technique is called a "re-trace" and is also useful with the figure-8.

  • Only retains 50-60% of the webbing's strength.[SP96, p51]
  • Does not require overhand backups in webbing. Be sure to leave the tails several inches long though.
  • Dress knots in webbing carefully so the two strands remain flat and parallel to each other.
The Water Knot and the Double Fisherman's Bend
Water knot Water knot (in webbing) Water knot (in webbing) Water knot (in webbing) Double fisherman's bend Double fisherman's bend
Water knot (This knot is usually tied in webbing, but rope is shown for clarity.) Start with an overhand knot in one line. Re-trace the knot with the other line. Dress and set. Double fisherman's bend Double fisherman's bend

Double Fisherman's Bend

The double fisherman's bend (or grapevine knot) is a very secure knot that can be used to bend two similar pieces of rope. It is prone to jamming with heavy loads and can be difficult to remove. With three turns on each overhand, it is called a triple fisherman's bend or barrel knot. The triple fisherman's bend is as strong as the rope and is the only bend that should be used with Spectra[SP96, p52].

The double or triple fisherman's bend is often used to bend two lengths of rope that will be used for a rappel.

Animated double fisherman's bend

Square Knot

But employed as a bend [...], the reef knot is probably responsible for more deaths and injuries than have been caused by the failure of all other knots combined. -- [Ash44, #75]

The square knot (or reef knot) is a binding knot. It's easy to tie, compact, and can be tied while maintaining some tension in the line. If the tail and standing part of one of the ropes get pulled, the knot will capsize with one rope forming a girth hitch around the other. If this knot is used as a bend and something snags one of the ends, the knot can capsize easily. The problem is worse if the materials used are of different size or stiffness.

  • The most common way to tie a square knot is to take the two ends of the ropes and tie a half knot right-over-left and then another left-over-right.
  • The tails of the square knot should be parallel to the standing parts of the ropes and on the same side of the knot.
  • Use the square knot to tie the free ends of a coil of rope.
  • Use square knots to tie a seat harness with webbing.

The Wrong Way

There are three incorrect knots you can end up with when you attempt to tie a square knot. Which one you have is determined by the orientation of the tails with respect to which side of the knot they are on and if they come out of the knot along side of the standing part.

  • Granny Knot - This is probably the most common error. The tails are on the same side of the knot, but do not follow the standing part out of the knot. If you intended to tie a square knot with the right-over-left left-over-right method, you got one of them backwards. This is the only one of the three incorrect knots you can end up with when using that method of tying. This knot is not secure and will pull out of most materials. Don't use it for anything.

    Look down at your shoes. Are the loops of the bow knot extended across your shoe or along its length? If the loops go along the length, you have the granny form of the bow knot. Fix your shoes before someone notices.

  • Thief's Knot - This knot has free ends that come out of the knot parallel with the standing part of the rope, but on opposite sides of the knot. It will not support much of a load and should not be used in rigging.
  • What Knot - This knot has free ends that do not follow the standing parts out of the knot and the tails are on opposite sides.
The Square Knot
Reef knot Reef knot (capsized) Granny knot
Square knot (unsecured) Square knot (capsized) Granny knot

Animated square knot

Bowline

The bowline is the King of knots because it is strong, secure, and versatile, as kings should be. And simple, as kings generally are. -- [Tos98, p 62]

The bowline creates a fixed loop on the end of a rope. Four of the required knots are based on the bowline (bowline, mountaineering bowline, bowline on a coil, bowline on a bight) and knot texts will show many more variations. This knot is easy to tie, easy to inspect, and not prone to jamming. After you learned to tie your shoes, you should have learned this knot. If you didn't, learn it now.

  • The free end must have a backup knot. The most common choice is the overhand knot. An even more secure choice is the double overhand knot. A Yosemite tie-off will put the free end of the rope outside of the loop.
  • The single bowline can be re-traced to form a knot with the same structure as the bowline on a bight.
  • The free end should be inside of the major loop (except with the Yosemite tie-off). Although the "left-handed" form of the bowline is thought to be just as strong as the properly tied version, the free end is more likely to snag on something and capsize the knot into a slip knot.
  • When a bowline is tied around something, it is easy to tie if you start with an overhand knot. See the section on the helical knot for an example of this method of tying.
  • The bowline is not suggested as a main rigging knot. Use the mountaineering bowline instead.
The Bowline
Bowline Bowline Bowline with overhand backoff Bowline Bowline with Yosemite backoff
Tying the bowline Bowline before setting and securing Finished bowline Securing with a Yosemite finish Bowline with Yosemite ready to set

Animated bowline

Mountaineering Bowline

The mountaineering bowline (double-loop bowline or double bowline) is identical to the single bowline except that it has two minor loops. It is stronger and more secure than the single bowline. One of the backoff methods used for the single bowline should be used with the mountaineering bowline.

The Bountaineering Bowline

Mountaineering bowline Mountaineering bowline
Method of tying the mountaineering bowline Mountaineering bowline (not secured)

Bowline on a Coil

The bowline on a coil is used to attach a person to a belay line if a harness is not available. The use of multiple major loops (usually three) helps distribute the load and is more comfortable for the person on belay.

  • A rope in not a harness. Use this knot only in cases where a harness is not available and no webbing is available to tie a harness.
  • This is not a knot to be used in equalizing rigs. All of the coils must be around the same object.
  • The orientation of the minor loop and the way the end of the rope passes through it are the same as a regular bowline.
  • The bowline on a coil should be secured with an overhand knot around all of the major loops[GH97, p123].

The Bowline on a Coil

Bowline on a coil Bowline on a coil Bowline on a coil Bowline on a coil
Starting position. The coil that makes up the major loops would be around your waist.   Before setting Set and secured. Note that the backup knot goes around all of the loops.

Bowline on a Bight

The bowline on a bight is a mid-line knot used to create a fixed loop.

  • You can tie this knot around something by tying a single bowline with a long free end around the object first, then re-trace the free end through the knot.
  • The relative size of the two major loops can be adjusted.
  • This knot may be used in an equalizing rig and it is the only one of the required knots that can be.

The bowline on a bight

Bowline on a bight 1 Bowline on a bight 2 Bowline on a bight 3 Bowline on a bight 4
Start by forming the minor loop in the bight Pass the end of the bight through the minor loop. Spread the end of the bight to form a loop and fold it back over the knot. Bowline on a bight before setting. Completed knot.

Figure-8

The figure-8 knot can be used as a stopper knot (e.g. to prevent a rope from passing through a pulley). Its more common uses are in the forms tied in the bight or re-traced. No securing knot is required, but many people prefer to add an overhand backup.

High Angle Rescue Techniques[VH99, p 62] lists the following as reasons the figure-8 family is preferable to the bowline family:

  • more likely to be tied correctly
  • more likely to be remembered
  • a lot easier to tell if it is tied correctly
  • remains stable if loading comes from a direction different from what was intended
  • more likely to remain tied after repeated loading and unloading
  • less likely to invert and become untied when pulled across an obstruction or when the tail of the knot is pulled
  • tends to weaken the rope less

I still prefer the bowline in a lot of situations. The bowline is a lot less likely to jam and it consumes much less rope than a figure-8.

The Figure-8

Figure 8 figure-8on a bight figure-8on a bight figure-8bend
Figure-8 Figure-8 on a bight before setting Completed knot Re-traced Figure-8 on a bight used as a bend

Animated Figure-8

Figure-8 on a Bight

A figure-8 knot can also be tied in a bight to form a fixed loop. This knot is usually tied near the end of a rope and used as a main rigging knot. The same knot can be tied by tying a figure-8 in the rope, passing the free end around something, and re-traced the knot. Re-threading a figure-8 with another line will form a figure-8 bend, a very secure knot.

  • Use as a main rigging knot.
  • Use to form fixed loops on climbing slings.
  • Use to form a fixed loop in the end of a rope being lowered down a drop for rappelling.
  • Requires some attention to dressing.
  • Does not require an extra knot to secure.
  • Use an alpine butterfly or an inline figure-8 if the knot is to be loaded in opposite directions on both tails.

Münter Hitch

The Münter hitch (or Italian hitch) is a friction hitch formed from a rope and locking carabiner. It can be used to belay single-person sized loads and can serve as an emergency rappel method.

  • The Münter hitch will automatically reverse directions depending on if you are letting out or taking up rope. You should set the knot in the direction you are going to use it to avoid several inches of slack when the knot reverses.
  • The carabiner must be the locking type, and it must be large enough for the knot to pass through when changing directions. A pear-shaped locking caribiner is the preferred type.
  • The Münter hitch provides good friction no matter what the angle between the ropes and caribiner. (Some belay methods using devices like a figure-8 are quite sensative to the angle of the ropes.)
  • When used as a rappel method, the Münter hitch kinks the rope more than other methods.
  • The Münter hitch may be used to provide extra friction to the rope feeding into another rappel device.
  • The Münter hitch is commonly used as part of a load releasing hitch.
  • The Münter hitch may be locked off with a mule knot.

The Münter Hitch

The Munter hitch 1 The Munter hitch 2 The Munter hitch 3 The Munter hitch 4 The Munter hitch 5
Form a bight in the rope. Grab the end of the bight and twist it once. Grab the end of the bight and twist it again. Attach a locking carabiner. Set the knot by pulling the end of the rope that will be attached to the load.

Method to tie the Münter hitch
Mule knot method to tie off Münter kitch

Alpine Butterfly

The alpine butterfly (or lineman's loop) is a mid-line fixed loop. It can support a load in either direction along the main line.

  • Use to bypass a damaged section of rope. Two alpine butterflies and a carabiner can be used to bypass a longer section of rope.

The Alpine Butterfly

Alpine butterfly 1 Alpine butterfly 2 Alpine butterfly 3 Alpine butterfly 4 Alpine butterfly 5
Grab the main line and turn once to form a loop (shown). Turn again to form a second loop. Fold the second loop over the first. Pass the second loop around the main line and through the first loop. The completed alpine butterfly before setting. The completed alpine butterfly. Note that the loop should be longer than shown.

Animated alpine butterfly

Helical

The helical knot (or, ascender knot) is a friction knot used with rope climbing systems to attach a smaller sling (7-8mm) to the main line (11mm). When there is no tension on the sling, the knot slides freely. When the sling is loaded (parallel to the main line), the knot grips the rope and will not slide.

  • This knot is usually tied with four or five turns around the main line.
  • The figures show the knot joined with a bowline. This is the most common way to tie the Helical knot, but careful attention must be paid to securing the bowline with an overhand knot, or better yet, a double overhand or Yosemite finish.
  • A figure-8 tie can also be used.
  • The helical knot may be adjusted without detaching the other end of the sling from your harness.
  • The helical knot is a bit harder to tie than a prusik, but moves easier and grips the main line more securely.
  • If necessary, this knot can be used to attach a flat webbing sling to the main line.
  • It is best to tie this knot with a minimum of slack. It will stretch when loaded.
  • Never apply any downward pressure on the top coils of a loaded helical knot. This may cause it to slip. If it slips far enough to press down on the top of another knot, disaster may result.
  • Slide a helical knot up the main line by pushing it up from the bottom, not by gripping the knot.
  • Tie the top knot first and remove it last. That way you will not end up hanging by your heels if you slip.

The Helical

Helical 1 Helical 2 Helical 3 Helical 4
The helical starts with four or five wraps around the main line. The overhand method of tying a bowline. Start with an overhand knot and pull the end to form a loop. Finish the bowline. Knot before setting and securing. Remove as much slack as possible and use one of the usual methods for securing a bowline.

Prusik

The prusik knot is a friction knot similar to the helical.

  • Once set, the prusik knot must be loosened before it will move freely. It is this property that makes the helical knot more popular for ascending.
  • The prusik knot may be loaded in either direction.
  • The prusik knot is often used to attach rope pads.
  • The prusik knot is used as a safety in hauling systems.
  • Tie the top knot first and remove it last. That way you will not end up hanging by your heels if you slip.

The Prusik

Prusik 1 Prusik 2 Prusik 3
Begin with a figure-8 on a bight. Pass the sling and knot around the main line and through the loop. The finished prusik.

*** [back to top of page] ***

A Few More Good Knots

In addition to the required knots, there are a few more knots which are being used frequently by cavers and worth learning or at least recognizing.

Mule Knot

The mule knot can be used to tie off a Münter hitch.

Locking Off the Münter Hitch with a Mule Knot

The Munter hitch 1 The Munter hitch 2 The Munter hitch 3 The Munter hitch 4
Form a loop in the free end close to the main knot. Pass a bight from the free end around the standing line and through the loop. Set the knot and pull a long loop through. Secure the loop to the standing line with an overhand knot.

Doubled Tucked Sheet Bend

The sheet bend is a knot used to bend two ropes of unequal thickness or stiffness. The thicker or stiffer rope is used to form a bight, and the thinner or more flexible rope is passed through and around the bight. This is a knot subject to some controversy. Depending on which reference you use, the standard sheet bend will be shown with the tails on the same or opposite sides of the knot. Some references show both and call one "left handed" and claim it is inferior to the other. The references that the author trusts the most ([Ash44, #66][Day86, #31][Tos98, p68]) all show the proper knot with the tails on the same side.

An examination of the knot offers some insight in to the controversy. Ashley explains:

The so-called oft-quoted "principle of the knot," that "no two parts which would move in the same direction, if the rope were to slip, should lie alongside of and touching each other," plausible though it may appear, does not seem important. -- [Ash44, #64-65]
An excellent example of this is the sheet bend. The sheet bend (#66) violates the alleged "principle" at every point where it can, but it has good nip and does not slip easily. The Left-Hand Sheet Bend (#67) conforms to the so-called "principle" to a remarkable extent, but has poor nip and is unreliable. -- [Ash44, #66-67]
  • Can be used to bend ropes that are not the same diameter or even to attach webbing to a rope. The smaller or more flexible rope should be tied around a bight of the larger rope. In the pictures, the bottom (light-colored) rope would be the smaller or more flexible one.
  • Securing this knot is required.

The Doubled, Tucked Sheet Bend

Sheet bend (standard) Sheet bend (doubled) Sheet bend (doubled,tucked) Sheet bend (doubled,tucked,secured)
Sheet bend. Note the orientation of the tails. Double sheet bend Doubled, tucked sheet bend ready to secure. The finished doubled, tucked sheet bend

Animated sheet bend

Double Figure-8

The double figure-8 is similar to the figure-8 on a bight, but it provides two loops (which may be of different sizes). This is the knot of choice for equalizing rigs. (See [SP96, p 46].)

Figure-9

The figure-9 knot is similar to the figure-8 on a bight. It is used for the same things as the figure-8, but is claimed to be stronger and less likely to jam. The strength factor may be significant in rigging using rope of 9mm or less. (See [SP96, p 46].)

Load Releasing Hitch

The load releasing hitch is used to attach a load to an anchor when it may be necessary to release the load in a controlled manner, such as moving the load to another anchor. (See [SP96, p 226].)

Inline Figure-8

The inline figure-8 is used to form a mid-line loop where the tension on the loop is in the same direction as the tension on one of the tails (such as to a backup anchor). (See [SP96, p 49].)

Additional Information

Books

  • On Rope[SP96] - Considered the best reference on North American rope techniques. Knots, rigging, safety, equipment, and many other subjects are covered. The illustrations are good for learning to tie knots. I think every vertical caver should read this book.
  • The Handbook of Knots[Paw98] - This is the book I recommend if you want a good general-purpose knot reference. The book covers a fair number of climbing knots and has very good color photographs. Amazon.com has some sample pages you can preview.
  • Art of Knotting and Splicing[Day86] - My favorite general-purpose knot book prior to Pawson. The book uses black-and-white photographs to show the knots and has some discussion on techniques of tying them.
  • The Klutz Book of Knots[Cas85] - This is a small and inexpensive book that covers 25 of the most useful knots. It comes with cord and has die-cut cardboard pages so the knots can be practiced next to their illustrations. It is an ideal book to get people started with tying knots that are useful for everyday life.
  • The Morrow Guide to Knots [BR82] - This is one of the most popular books on knots. It has step-by-step color photographs and shows multiple techniques for tying knots. I find Day to be a better reference since this book is lacking several of my favorite knots (alpine butterfly, Ashley's bend, buntline hitch, and a few others) and it is not as thorough in its text.
  • Vertical[War94] - Knots, rigging, safety, equipment, and many other subjects with a focus on European (or Alpine) techniques. This book is a great companion to On Rope.
  • Mountaineering: The Freedom of the Hills[GH97] - Broad survey of mountaineering topics (camping, rigging an knots, climbing, rescue, much more).
  • CMC Rope Rescue Manual[Fra98] - Another general-coverage book. The focus is on rescue rigging and not caving.
  • The Ashley Book of Knots [Ash44] - Probably the most complete collection of knots ever assembled. 3800 knots and variations are described. Ashley is referenced in almost every other knot book. This book is fairly old and it does not account for caving/climbing applications. The illustrations are not all that good for learning to tie the knots.
  • The Complete Rigger's Apprentice[Tos98] - This book focuses on rigging for sailing. The chapters on knots, tricks and puzzles, and "sheer ingenuity" are probably the most useful. If you are blessed with a need to work with wire rope, there is also a lot of material on its splicing and use. Toss is expected to release a new book called Working Knots sometime in the summer of 2000.

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