Nautile aka Charles Hamel's personal pages
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Identical diameter for each cordage in it.

(Aparte note : capsize / collapse / roll / walk / collapse/ become undone / flip / invert / slip /
slide / pull out.... so many words I have seen used - unclear, really unclear to me!)

"Every one knows" -a good way to start to state an 'unexamined' affirmation-  that a square
knot or reef knot can be made into another knot , a lark's head, by forcibly pulling at the
same time on its tail and SPart .
( more later about what seems to me
- either some condition akin to  frenetic delayed echolalia or  involuntary parrotlike repetition (echoing)
of a word or phrase just spoken { little me : in the case in point it is  'written by another person'. - though
it remains to be seen if the involuntary trait is verified or it is is wanton.}
- or it could be a lower order phenomena : medullary  reflexive arc unlinked to any descending inhibitory
tract  or may be "mental rheumatism" causing limping ( may be  limp too) thinking, leading to sternly
echo dire warnings about it without probably having ever made any investigation and experimentation
whatsoever before going on auto pilot with this litany

Can you tell, without fail, what happen to the "crossings" in such a transformation ?
Where do  they go? 
Which one is kept intact in the same place and of same nature ?
Which one is "translated" ?
Which one is "destroyed" ?
Which one is "created" ?

Take a piece of cordage, or paper and pencil and try to write an answer before going to see
what indeed happen.

Learned something ?
Well I did when doing that little experiment.
Shame should not be felt for not knowing but for not accepting to learn.

" never, never, under any circumstance use this knot as a bend , it is only a
binding.... " and so forth.
A forceful unsubstantiated affirmation stated with a strength of conviction inversely
 proportional to the documentation offered.

Stating opinion or even knowledge about "a knot" without clearly telling to which specific
use it was put , the material(s) in which the cordage is made,  the diameter of the cordage ,
the nature of the cordage 'making' : laid, solid braid, braided sheath with 3S core, braided
sheath with parallel fibres core, hollow braid, number of braiding ( 4,6,8,12,16...)
relatively meaningless.

Some knots that were paragons of virtues in the hemp / manilla / flax / cotton days are not
to be 'automatically' taken as such in nylon, or polypropylene or any post 1950 material.

If the reef knot has one big default it is its jamming potential.

It is easy to get an unloaded  reef/square to capsize, easy in term of force but not of
specific actual circumstances in real life. 
There is only need to overcome what remain of the tension that was put into the knot when
setting it.

This is why it is  useful in sailing : there is -there should not be any tension applied to -
 'no tension' in a reef knot that is why it can be undone so easily with one hand.

If you do not apply -directly or indirectly- equal tension on both the WEnd and the SPart
of the same cordage in the reef knot it will not come undone.

If you use a reef bend :

- - - be sure to  dress it and set it with the very maximum of force you can give before
using it.  (not fully setting some knots may be deliberately used to keep that as a braking
or shock absorbing "reserve" but make sure that their tails are longs and/or 'secured')

- - - for my part I do not forget to follow the rule I was taught so many years ago, in
Brittany by people earning their bread on the sea all year long :
always leave long tails (6 to 10 times the diameter or even more : the bigger the rope the
higher the multiplying factor)

Please try to refrain a few seconds from immediately thinking  that this is the sign of a
bad knotter, - that would just be prevention and a priori judgment -, may be it is the
sign of  experienced ones !  Even if it is a 'bad knotter' way and mean, I have
always, till now,  seen it serve in good stead.

Just take a look at what can be seen in fishermen's harbours, not in the Sunday, leisure
cruisers harbours, but in commercial fishermen's.

Of course there are some times when long tails are impractical so just secure the tail in
another way.

The worst thing - beyond urgency time - is to fall back on pre-set response ; always
stop, think and adapt to the local ( space and time and opportunities ) conditions,
diving just reinforced my professional training in that direction.
Tailored suits are generally better adapted than ready made one!

Very often a knot will slip a bit to begin with when getting under its actual load and then
will settle and then fully set, this can be seen even if it has been set manually.

This do not happen to an identical degree  with small or large diameters of cordage
but I find that the bigger the diameter the longer the slip may be.

( This question of "size" is something often forgotten in many discussions : 'scaling'.
Example : length goes by power of one, surface by the power of 2 and volume by
the power of 3, that is why gigantic ants are a 'no go'.
Scaling and the nature of the material the cordage is made of are of great importance)
You tested a 8mm cordage with 40 kg, to test 'to scale' a 2 mm cordage you should
load it with  2.5kg and not 10kg. Weight is applied by 'surface of section" so if you  
divide the diameter by 4 your divide the section by 4x4=16 so you must divide the
weight by 16 and not by 4. )

If you have not left enough tail length to 'pay' for the slipping you will run the risk to
be bank routed.

It is difficult to capsize a reef knot under a heavy load.
Please do not believe me :

Just go take a hemp or manilla 6 to 8 mm of diameter cordage. ( Nylon , PE, PP...
will have different behaviours )

Suspend one extremity to a secure fixed point.
At the other extremity put (knot fully set by hand and no shock loading) a 50 kilograms
50 kg translate to 7.8 stone or about 17.5 % or 11 % of the strength for these diameters
 as the reef knot leave remaining 50% of the maximum strength of the unknotted cordage
 that is about safe.
Go ask your friendly car mechanics to help you with his elevating platform or his
 'cranking' block of pulley.

Now use your best hand and pull one of the tail of the reef knot to make it capsize. 
Please try again.
Harder please !
Not SO easy to get the capsizing, is it ?
My own Simple explanation.

Well you had to overcome the setting put in the knot plus about 70% of the load on it
when pulling at a 45° angle.

That will be more that 106 kg for a load of 150 kg.
Do you really think that you can easily spill it with a flick of a finger, or "the brush of a
shroud" ?


Some 'muscular physiology' facts showing that most people will not capsize a reef knot
put under a 80 kg load  :

Muscular strength ( untrained, naive, proverbial "average" individual) is very much under
most rope breaking point.
Most would not even begin to really strain a plaited cotton mason chalk rope with a
32 kg  (70.5 pounds if I am not mistaken)  breaking limit.
In a French survey of 92 young men aged 19-20 randomly taken from the general
population the maximum force for elbow flexion in the dominant upper member show
that  95% of population is roughly between 212 N and 353 N that is  that is less than
22kg / 48lb at  lowest -  36kg /80 lbf at upper limit. ( mean being 283N)
Another study give for upper member *forearm totally extended from the arm*,
held 30° under the horizontal and at 45° ABDuction (arm opening away from the
body axis, and in the body plane) give :
47kg pulling towards the body axis 
27 kg pulling upwards and 26 kg pulling downward
24 kg when closing the angle coming toward the body axis
15 kg opening the angle away from the body axis.
I have no notion of repartition of age classes age and size of sample : only that 
was in a study on muscles and skeleton disorders afflicting  workers used to
heavy and/or repetitive loads in their working hours.

Ever thought about the cycling stress your shoes laces 'binding' is subjected to in
a day of walking ?  
If someone own a  gauge please do your shoes laces as usual and measure the
"pull" applied when you walk.
I would be curious to know the result.
Think 80 paces a minutes in brisk walking that is 80 x 60 = 4800 in an hour of
I really cannot remember the last time I have had to "re-do" my lacing in the last
50 years, and I walked quite a lot in my life  and get up and down quite a number
of steps in my medical life, doing "home visits", well the reef bend was performing
quite well I can tell you.

I have some questions and remarks :

- where are the statistics about " all the deaths"? Never found one.
- where is an 'actual' verified, testimony ?
- where are the official reports about such a death ?
- where are the "tests" done on reef knot in all manner of cordage ?

- there was a time (hemp / manilla cordages) when it was used in mountaineering.
If it had been "an assurance of death" I think that there would have been less
enthusiasts "à la belle époque".

- it is used  to join two cordage that will served as tow line by professional fishermen.
( I  have seen it )

- it is used
( I met a man who learnt it from his grand father who had had it from his own father who....)

in Brittany to join two length of  'line'
(name is ' de la ligne' / that is a cordage designated by the label of 'line' to be differentiated from
the 'piece of rope' that is 'une ligne' / a line  -  nowadays it is thin  braided nylon, coloured as a
 tarred cordage , before it was hemp or the lesser quality cordage made of manilla )

to make the piece of cordage joining the pot to the float that allow to know where it is.
Well they have yet to lose a pot because the knot capsized.

By the way : this is a glass float made in France, they were in use in Brittany till the 60'.

This one was given to me by the guy, Jean-Paul Lemoigne, who make these
 beautiful half-hull . Jean-Paul refuse to use digitally driven machines and do it all the hard  
old way.
The 2 dark brown ones are made of wengé wood specially for me (he dislikes working
very hard wood which 'destroy' the edge of his tools ) as a friendship gesture after so
many years of  'going there".
His father was a fisherman on  "Notre-Dame de Rocamadour, a lobster boat that was
fishing off Mauritania, which you will see on the slideshow about Douarnenez museum

One guy on a quay in Camaret ( Prequ'île de Crozon, South of Brest in Brittany just
try to visit France by proxy)  had a good laugh at me when I said
 " this knot which is not.... is not to be use...if one had to follow the opinion of some."
He was laughing shaking his head in disbelief and calling guys around to witness before
I had reached the '...' part in my sentence.

Had to win back his respect before going on about bowlines (see next topic) which got
more head shakes.

After that little innocent question the guy was taking me for an ass (the donkey sort!) till I
decided to take him up on the use of the brand new fid he was holding in hand and
passed on to him a trick or two on the Swedish fid. They were not liking this fid at all but
the 'coopérative' had no normal fid left.

By the way : if you roll a splice under your foot over there you are done for :
for them it is THE landlubber tell tale sign , a splice done in the correct manner at
each move does not have to be 'rolled' under foot.

My findings :

- the way you set it is a very important point for performance.

But is not that the case for all knots ?

The goal of a correct setting  is to maximise the surface of contact between
different parts of the cordage inside the knot. This in a stable disposition while
simultaneously making sure that the disposition will maximize the 'pressure'
applied on these surfaces of contact when the load is applied.
Must be done in such a way that the more load is applied, the more friction is generated,
all the while making sure to give the best D/d ratio to the fibres in the cordage.

- even with a cheap highly springy and sleek fibrillated polypropylene 8mm 3S laid
cordage (I wonder why they produce this sort of junk ? , even the Constrictor does
not hold a cyclic loading with it! May be it is an experimental testing material for
knotters ? ;-)  ) it can be made staying put : just dress perfectly and maintain it
under tension all the time.
I would certainly not go over my balcony with it though!
In that polypropylene if setting is not absolutely top then the knot readily slides and
separates at the least loading.
If tension is relaxed a small bit and then re-applied then it readily slides as the
"springiness" make it  'undress'.
Just show that when one discuss a knot one had better say what sort of cordage
was used.

- in 16mm Nylon (braid sheath, parallel fibres core) it held nice and well,  setting
was quite easy. Suspend my full weight on it  with no particular precaution several
time. Perfect behaviour.

- in 3mm braided polypropylene cordage :
    * 50 shock loading ( 20 kilogram free falling for 10 centimetres ) : quite unaffected.
    * My best pulling ( ouch it is cutting in the skin!) left it quite unaffected
    * doing the experiment I proposed at the beginning of this paragraph with only
20 kilogram load :
when the angle was still a bit less than 45° but immediately lock in the
new disposition. ( 6 times out of 6 )

(I will leave you experiment - always taking great care to avoid any bodily harm to
anyone- beyond laid hemp, braided polypropylene and these diameters I used  
because the 'behaviour of a knot' is not independent of the nature of the material,
the nature of the "making" ( lay - braid...), the diameter, steady progressive and
continuous load or shock load, unique or multiple....)

-in 2 mm, 3 strand laid nylon with the knot soaked in WD40 in the hope of making
it slippery : I suspended my little 73.7kg self (have no fear I may be a stark raving
mad French lunatic who holds the Reef as being a true bend , a fool in short,
I am not stupid, my feet were safely some centimetres above the floor ).
I did not wait and used it immediately after soaking it as I was not all that sure that WD 40
agree with nylon after a few moments .

Did this 9 times without any progressiveness in putting my weight on it though not
 trying to shock load it.
I am still waiting to see the reef knot slip or capsize.
In spite of the heavy duty gloves I had done I finished with angry purple welts on
my fingers. 
Must have been a fluke surely !
Nylon was given for 120 kg so 73.7:120 =  61% so the reef must be much better
than the 40%-50% remaining strength, another fluke surely or within the statistical
variation (standard deviation was not given)

When making use of a reef knot (any knot in fact) I always make sure it is
 "freshly done" by myself.

I would never use one, even one of mine that has been left  alone for some time.  
In fact I abstain from leaving knots in a cordage as this is quite detrimental to it.

Do not - just as a precautionary principle as there are better ways to proceed
 - suspend a living creature from it or put a living creature under a load put on this
knot, or any other knot or load for that matter.

For each sequence ( successive or consecutive , immediately following each other
or with a very short interval) of use of a same - as in very same individual knot
-  reef knot I make sure of its setting.

You will find "le noeud plat" ( that is the Reef K.) in the official ( published in 1875
by Minister orders ) Manuel Du Gabier.

This official French Navy Manual put it as something that it was compulsory to know
to get a " gabier" brevet.

It is Fig 2 on Page 2 with this text :

"Ce noeud sert à réunir deux bouts de filin qui ne doivent pas faire une grande force.....
Il sert également à terminer un amarrage.
Quand il a forcé, ce noeud est souvent difficile à défaire"
"This knot is used to join together two ends of rope which are not to be submitted to
great force...
It is also used to finish a seizing.
When it has been heavily loaded, this knot is often difficult to undo"

I read the warning we find here and there, first of all  in the Manuel du Gabier, about
not overloading this knot, not as a warning about not using it because it will slide or spill,
but because it will be difficult to undo it if it has been heavily loaded.
Hence the warning do not overload it!
This warning has been , IMO, quite misread or rather mis-interpreted ( not analyzed at
 all IMO)  as : "beware, it is no good, it spill".  That is not in the words.

This knot is still :
- taught in fishermen professional schools in France.
- retain in the program of our diving federation ( FFESSM Fédération Française
d'Exploration et de Sports sous-marins ) "pour les cours de matelotage"  for seamanship

Do you really think that it is because they are less intelligent and informed than all the
"Cassandra" giving external signs of speaking and writing under the influence of
"parrot programming".

Not once have I seen someone taking pain to argument the affirmation beyond the fallacy
of " argumentum ad baculum" or "appeal to authority" or "anecdotal or hasty unexamined
generalization" or "bandwagon consensus" or....

It is not because menacing warning is used (argumentum ad consequentiam, another fallacy),
 or appeal to an unsubstantiated published assertion is made ( ABOK being a case in point
on this particular topic), or just some bad event is known, most often just by hearsay ( the
man who knows the man who knows the man who knows the man who saw the bear -
just happened that too often there never were a bear in the first place, or a 2 days cub),
 or because the idea has got the consensus of the "followers" that it makes it to be 'the
incontrovertible  truth'.

I could as well out of the blue state something like :
" Sheet Bend is no more secure than Reef Bend".
Beware! this may not be so far from containing some 'truth'.

That will not hinder people to go on writing or saying " do not use the Reef, use a Sheet
instead, marvellous bend the Sheet is ".
Remember : Reef is for to equal diameter cordages, Sheet is meant for two different
diameters; but not too different ; just try it with a 2mm on a 30 mm and we will speak
about it again.
Are you so sure that the Sheet is so much better ?
Or is it just another unexamined credo?

A 18th century knot in use in artillery.  (I have some doubt about the old drawing that
comes from !)

I will retain the noeud plat or noeud droit as
-- a good 'noeud d'ajut' (bend in English) and not only as a binding though this is its safest
area of use,
-- to be put to use as any knot, any tool, as it is meant to be, that is observing 'indications',
'no-indications', 'contraindications' and possible 'adverse effects'.
Try using a chisel as a screw driver or a screw driver as a chisel and you will find that they
are both "useless, good for the junk pile..."
Of course they were not meant to be used in such a manner.

Would you say that antibiotics are to be discarded because they are useless in a brain
tumour or that surgery is useless because you cannot apply it to cure a flu syndrome ?

How about two persons in a heated discussion ,
one saying " no! believe me, elephants are much better"
and the other " I tell you: fruit flies any day it is for me" ?

Well the first one is the manager of a circus and the other is a geneticist.
It all depends upon perspective.

Nevertheless you better stay safe and retain  " never, never, under any circumstance
use this knot as a bend , it is only a binding.... "

A last advice , please take every precaution possible about going to lie on a bed.
So many people die in a bed!
One of the most unsafe place in the world it is apparently.
May be we should think about discarding them altogether along with the reef knot !  ;-)

                                        Go to page 8 of  bat's belfry

Copyright 2005 Sept - Charles Hamel / Nautile -
Overall rewriting in August 2006 . Copyright renewed. 2007-2012 -(each year of existence)

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