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Phil Benchoff
November 16, 2002
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.
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.
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.
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.
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
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]
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.
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
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| Overhand knot |
Overhand knot (inside) |
Overhand knot (outside) |
Double overhand knot |
Double overhand knot |
Animated overhand
knot
Animated double overhand
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
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| 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 |
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
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.
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.
The Square Knot
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| Square knot (unsecured) |
Square knot (capsized) |
Granny knot |
Animated square
knot
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
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| Tying the bowline |
Bowline before setting and securing |
Finished bowline |
Securing with a Yosemite finish |
Bowline with Yosemite ready to set |
Animated 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
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| Method of tying the mountaineering bowline |
Mountaineering bowline (not secured) |
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 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 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.
Animated Figure-8
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.
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.
Method to tie the
Münter hitch
Mule
knot method to tie off Münter kitch
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.
Animated alpine butterfly
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 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.
*** [back to top of page] ***
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.
The mule knot can be used to tie off a Münter hitch.
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.
Animated sheet
bend
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].)
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].)
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].)
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].)
- 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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