Knot for closing a trawlnet
Jerôme Nimo
I am looking for the description (text, image, whatever) of the knot used to
close the end of a trawlnet. This knot is named 'raban du cul de chalut' in
french, but I do not have the slightest clue about how it is called in any
other language.
I have looked up my books (incl.ABoK, Budworth, etc.), spent time googling
web sites and newsgroups, including rec.knots, paging through web pages of
knots, to no avail.
Could somebody provide me some link or pointer?
Thanks in advance.
j.
roo
can go on? Do you know what it looks like (even a little)? Is it
like a binder or a hitch, or a bend, or a loop, or some sort of
adjustable knot? What are its functional characteristics? Is it
supposed to release easily? What type/size of material is it usually
tied in? Etc.
Too much info is better than not enough.
Jerôme Nimo
<roo...@yahoo.com> a écrit le 18/02/03 7:34 :
> Unfortunately, I don't speak French. Do you have any other clues we
> can go on?
ok. please excuse any misusage of words, as I do not pretend to master the
vocabulary of knotting matters, esp in english.
> What are its functional characteristics? Is it
> supposed to release easily?
It is used to keep the end of a trawlnet closed during trawling, and has to
be released quite easily when the full trawlnet has been hoisted back on
board, so that all fish can 'pour' out of the net. The knot has thus to
whistand quite high forces (during trawling and hoisting) and still be
releasable quickly and easily.
I guess there must be some trick built in to allow sort of a remote release,
as even if those sailors are strong and tough guys, there surely wouldn't
like to be too close the net -and the fish- when the knot is set loose.
> Do you know what it looks like (even a little)? Is it
> like a binder or a hitch, or a bend, or a loop, or some sort of
> adjustable knot?
From the single photo I found of such a knot (sorry no scanned version
available): it features a cylindrical appearance of a hangman'knot (or of
some stopper knots, such as
http://www.realknots.com/knots/stoppers.htm#muloverhand). No clue about the
way the running part exits.
> What type/size of material is it usually
> tied in? Etc.
from the same source, it seems to be tied in a medium sized (15 mm?) rope
(in this particular case, the rope was of some vegetable material)
> Too much info is better than not enough.
I am afraid this is still not much.
Thank you for any ideas or help.
j.
ben
>>>This knot is named 'raban du cul de chalut'
Hi there jerome and roo
It is not a binder or a hitch, or a bend, or a loop, or some sort of
adjustable knot
the narrow end of a trawl net is called a cod-end (cul)
it is a tube, that is closed with a line (codline)
the line is woven through the mesh of the net
both ends of the line are braided together with a sort of chain sinnet
(raban)
so the cod-end stays closed during fishing
(this is a tiny miracle, since the sinnet is dragged along the sea
bottom)
loaded with fish (among other stuff), the net becomes a dangerous
thing when lifted on board
someone grabs the long sinnet and gets out of the way
he opens the sinnet by pulling the ends of the line alternating (one
end, the other, first end again, each end repeatedly)
the 'cul de chalut' can even be streered while pulling the 'raban'
the 'cul' opens and fish poors out
it is a series of slipknots, with both ends involved
(a standard chain sinnet is made in one end of a line)
the sinnet must be the same as the raban, although I am not sure
I did not find a picture
but the following discriptions describe the same I think
http://www.netmarine.net/guides/dico/
Raban : Tresse ou sangle de 8 à 9 mètres de long formée d'un nombre
impair de brins de bitord. - de hamac : bout de quarantenier servant à
suspendre le hamac. - de ferlage : cordon ou tresse servant à serrer
une voile sur une vergue, un gui, etc...
French governement is clear about closing a trawlnet ^-_-^
http://www.legifrance.gouv.fr/texteconsolide/RHHBC.htm
V. - Raban de cul.
a) Le raban de cul est un cordage permettant de fermer la partie
arrière du cul du chalut et/ou des fourreaux de renforcement soit par
un noeud facilement largable soit par un dispositif mécanique.
Knotting in my mind,
Ben
roo
Very interesting!
-roo
Ian Wright
and I'll TRY to describe how to tie it.
IanW.
On Tue, 18 Feb 2003 00:02:16 +0100, Jerôme Nimo <jn...@bigfoot.com>
wrote:
Dan Lehman
> >>>the knot used to close the end of a trawlnet.
> >>>This knot is named 'raban du cul de chalut'
>
> It is not a binder or a hitch, or a bend, or a loop,
> or some sort of adjustable knot
Actually, it IS a bend: it joins two ropes (effectively,
though, yes, they're usually/always the same rope). And
it is a slipped bend, designed to be easily released when
loaded.
> loaded with fish (among other stuff), the net becomes a dangerous
> thing when lifted on board
> someone grabs the long sinnet and gets out of the way
> he opens the sinnet by pulling the ends of the line alternating (one
> end, the other, first end again, each end repeatedly)
This alternation depends on the knot--some don't require this, others
do (i.e., in some codline knots only one end is pulled to spill the knot).
> it is a series of slipknots, with both ends involved
> (a standard chain sinnet is made in one end of a line)
Again, this is one general variation: form a bight in one (long)
end-A and make a half-hitch around this with the other end-B and
insert a bight from end-B though the first and nip it by drawing
end-A's bight snug upon it; insert another bight from end-A though
the nipped bight of end-B and nip it by drawing end-B's bight snug;
... and so on. This sort of knot requires alternating pulls on
end-A & -B to spill the knot.
Such a knot is shown in Knotting Matters #9p.15 (km09:15), Autumn
1984. Another knot, in which the ends are tied as though a single
rope (i.e., run parallel/doubled), and hence pulled upon jointly
to spill the knot, is shown in km02:14 (January 1983). Pieter
van de Griend has a short article about both types of knots in
his self-publihsed book _Notes on Knots_ (March 1993); you can
buy this book from Des Pawson's Footrope Knots (get PvdG's _A
Letter to Lester_, while you're at it!).
Cheers,
--dl*
====
ben
> You are looking for a "Cod End Knot", if you can't find it call again
> and I'll TRY to describe how to tie it.
hi Ian,
is the (English) cod end knot what I think it is? (see earlier in this
thread)
and is it the same as the 'raban' ?
are you able to discribe it? or shall we leave it for a while, so the
other readers can puzzle a bit?
I can add a few things to my earlier description
Just to stimulate others to give it a try ;~)
It starts with a knot that resembles the "sliding sheet bend (sliding,
locking, exploding, non-whimpering)" mentioned by Peter Suber in
http://www.earlham.edu/~peters/writing/explode.htm#1
(I have seen this knot in use for cattle and horses too)
then there is a series of slip knots that form a sinnet
there is no finishing knot since that could get stuck and rip the net
apart
the ends are left as release for the slip knots
(some will actually release during fishing, but it will not unfold
like the standard chain sinnet)
it is very simple but it takes some experimenting to get an equal,
tightly knitted, nice looking sinnet
there are many ways to knot simple slip knots to a sinnet and they all
count as 'allright'
one version I like, is straight forward and gives a tight result, mere
triangular in diameter
normally you get an uneven, open woven cylindrical or flat sinnet,
that will do the trick
But it shows that you are unfamiliar with it, and the open chain can
still get caught while dragged along
So get some line an give it a try; and let us know here that you found
the solution
Whith this knot you will know when you succeed, as it works the way it
should (comprende?)
I learned it from a 17 year old seagoing fisher'man'
And still remember it as something special
Dan Lehman
---------------------------------------
It's unfortunate that none of my sources shows an
actual codend! --only the rope, in PvdG's case;
and only some rings, from Jim Garsides.
Rankin Codline Knot: this knot joins the center-of-codline
[^-- = boat name] bight with the paired ends.
The rope is centered, which means that a bight is pulled
out opposite and of equal length to the two ends. With the
net drawn as closed as possible (with some kicks perhaps),
a half-knot/simple knot is made (using the center bight and
the paired ends as though they are single ropes--this is the
case throughout), tightened, and then capsized such that the
ends form a half-hitch around the bight.
Then fold the bight over at a little bit shy of its center,
so that the bight end is the longer half.
With the paired ends, take a turn around the folded bight
near its end (i.e., close to the half-knot/net) and continue
this into a round turn EXCLUDING the bight end--so, one is
now wrapping around the bight legs and the ends.
Make another round turn, and this entails some further
tensioning of the initial half-knot closing the codend--one
is sort of jamming this turn (and another) between where
the bight-end is free of the turn and the codend.
After the 2nd round turn, continue wrapping with the ends
around the folded bight, towards its doubled-over middle
(a double bight).
With a bit of ends left, tuck then out through the doubled
bight; haul these snug to nip the ends by pulling the bight
end (which is under some significant nipping pressure of the
ends' turns).
(PvdG says (and shows) that the ends are each stoppered
w/overhands; but he shows these ends well removed from the
dbl.d bights' nip of the ends--so, I don't see how stoppers
would help, for by the time they reached that nip, the turns
would have to be so loose as to render the stoppers useless?!
A slipknot snugged against the bights' nip would make sense.)
To untie this knot, one works the dbl'd bights' nip loose
and pulls out the ends, then runs away with them; they need
only unwrap, and the knot spills the half-knot by the force
of the load of fish. NB: This is much simpler than doing
the alternating pulling on separated lines for the other
main form of the closure; moreover, there's really not the
kind of repeated nipping of a slip-tuck that must be opened
by strong jerks--once the nipped ends are freed, the rest
is just a matter of unwrapping!
Jim Garsides, apparently quoting _The Fisherman's Manual_,
shows much the same structure, but with some differences.
He says that a doubled line is run throught the set of net
rings, implying that the rings from opposed sides of the net
overlap and are thus locked closed; the bight end emerges
from one end of the now column of rings, the ends from the
other. Whereas PvdG's illustration implies a single line
run through a circle of rings and its center pulled out
opposite the ends, and these joined in the knot to tie off
the net. And Garsides images show the order of turns by the
ends to be done in the opposite order, with two final turns
being around the base of this structure close to the net;
but his text says that these turns are done in the MIDDLE of
the others--that one makes a couple around the doubled bight,
then the two at the throat, then more turns to finish the
knot before tucking the ends!?
(PvdD's method/knot seems to work well.)
--dl*
====
Dan Lehman
---------------------------------------
PvdG's 2nd knot is "Half-hitched Codline Knot"/"de Vlecht"
(Dutch)/"Poseknude" (Danish)/"Puckerstring Knot" (USA--but
I don't think PvdG's source gives an exact verbal descrip-
tion, and no image). His initial image is somewhat like
a bow tie in form: there is a horizontal paired line,
with bight-ends, one of which turns 270deg up under the
horizontal to form a large bight that would go around the
collar, the other's lower leg runs through this turn and
downwards, reflecting the large bight's other leg.
Precisely, starting from lower left with one end, to
describe the initial form (i.e., follow this path):
rope goes up (very slight tilt rightwards),
bends right to horizontal for a short span,
u-turns 180deg counterclockwise and runs horizontal,
back (left) above 1st horizontal segment,
just past the start's vertical rise,
u-turns counterclockwise (down&right) 270deg and
goes up crossing UNDER the two horizontal parts,
crossing at the start's first bend,
then forms an ample bight above (clockwise turn),
and right leg of this bight crosses down UNDER
the horizontal span.
From this position--which I take to indicate net rings
bound at each left/right u-turn'd bight--, the LEFT
end is slip-tucked (fold a small bight, ie) through
the "ample", upper bight (crossing OVER horizontal
span in reaching it--and all following such tucks are
OVER other material & down into bight), which is then
drawn down to nip it;
then the RIGHT end is similarly slip-tucked through
the left end's bight, which is then drawn down to nip,
then the LEFT end is slip-tucked ...
... and so on, until some adequate series of alternate
tucking/nipping is done, and the two ends are jointly
run out through a nip-bight and nipped, and each then
stoppered (and I've the same doubt about stoppers having
any effect as stated above!). I should note that PvdG
shows the orientation of tucked bights to be such that
in each case the end of the just-tucked bight lied to
the right of the to-be-tucked end; this makes for a
pretty, sennit-like structure, but I don't think has
much pratical effect.
Another writer--"a Danish marine engineer"--shows
the start of the structure to be what Kevin has drawn:
and end taking a half-hitch turn around a bight, and
that end then slip-tucked into the nip-bight, nipped,
and the process repeated w/alternate ends. But I
should expect this structure to deliver more force
upon the first nip-bight, and so be harder to spill
at the final moment. Or, as Ben has sharply noted,
<<It starts with a knot that resembles the "SLIDING
SHEET BEND (sliding, locking, exploding,
non-whimpering)" mentioned by Peter Suber in
http://www.earlham.edu/~peters/writing/explode.htm#1
>>
--dl*
====
Jerôme Nimo
Lehman <dan_l...@hotmail.com> a écrit le 24/02/03 0:33 :
>
> Rankin Codline Knot:
[snipped description]
Looks like the knot i was referring to: take a look at the photo i just
posted at news://alt.binaries.images.repost/BA807DE0.295D%jn...@bigfoot.com
(hope such an image fits the local netiquette; if somebody prefers a mail,
let me know).
the knotting of the ends of the line looks somewhat different from [my
understanding of] Dan's description, but these knots definitively have the
same general structure.
Regarding the alternative "Half-hitched Codline Knot", I've got to confess
that this description exceeds what my english can handle without resorting
to a detailed drawing...
Thanks for the help,
j.
Dan Lehman
> > Rankin Codline Knot:
> [snipped description]
> posted at news://alt.binaries.images.repost/BA807DE0.295D%jn...@bigfoot.com
CANNOT RETRIEVE ... is all I get when attempting this link, alas.
> Regarding the alternative "Half-hitched Codline Knot", I've got to confess
> that this description exceeds what my english can handle without resorting
> to a detailed drawing...
Okay, let's try ASCII art!
Precisely, starting from lower left with one end, to
describe the initial form (i.e., follow this path):
rope goes up (very slight tilt rightwards),
/
/
/
bends right to horizontal for a short span,
..........
/
/
/
u-turns 180deg counterclockwise and runs horizontal,
back (left) above 1st horizontal segment,
just past the start's vertical rise,
..............._
............|
/
/
/
u-turns counterclockwise (down&right) 270deg and
goes up crossing UNDER the two horizontal parts,
crossing at the start's first bend,
then forms an ample bight above (clockwise turn),
and right leg of this bight crosses down UNDER
the horizontal span.
_____
/ \
\ *C* /
| | CROSSING 0 IS OVER;
......2...3..... CROSSINGS 1..4 ARE UNDER;
| ..1...4.....| THUS, THIS MAKE A SLIPPED SIMPLE KNOT.
\0/_/ \
/ \
/ \
A B
From this point, leg A is folded into a bight and inserted into bight
*C* (i.e., slip-tucked), and *C* is drawn snug around it by pulling on
leg B. Then, B is slip-tucked into A's slip-tuck bight, A is pulled to
drawn that one snug, and so on, in alternation.
--dl*
====
ben
> Another writer--"a Danish marine engineer"--shows
> the start of the structure to be what Kevin has drawn:
I found a picture with this sennitlike form of codline knot
under the name of "butterfly stitch"
for a similar application, but (much) closer home
http://www.cam.com/gimp/bfly.htm
ben