Roo:
Thanks for the suggestions.
A stopper knot will stay in this tubing if the knot is wet. Perhaps I could prep the tube with a tight stopper knot on either end, pulled up when wet, and just leave those knots in permanently. Then any hitch made in the field would be more likely to stay fast.
The rope bent in the ends is also a great idea. I can’t wait to try these when I get home.
The picture of an Ossel Knot is wrong (and doesn’t agree with the narrative on the page anyway!). The final tuck goes under one part only not the whole set of wraps.
Barry
So, this material is not only elastic lengthwise, but also tubular , AND, as I learn now, other times it slips badly and other times it tends to stick to itself ! http://igkt.net/sm/Smileys/default/smiley.gifYes, it is quite peculiar and contrary stuff. I think knots are an appropriate tool to help make use of it - especially if the behavior of knots in tubing is well understood. I find it quite interesting to probe at the boundaries of the utility of knots in various materials, if anything to avoid overconfidence.http://igkt.net/sm/Smileys/default/smiley.gif
I wonder how much more peculiar a material can be… to make the life of a knot tyer difficult ! I guess it can also fold inside out, as a glove… and one segment of it can be inserted inside the other, ( i.e., be coaxial to another), so we end up having a double-skin tube. I believe that the knots made by this material belong to an altogether different world than the knots made by common material, and we should not try to solve problems originated in the one with solutions given in the other.
I’m looking forward to trying a few more of the suggestions put forth in this thread. I don’t know any more scientific method of testing their security than my informal battery of twisting, swinging, bouncing, yanking and otherwise vigorously loading the standing end. However, I would be happy to post the results of my informal testing as I try all your suggestions. I should probably begin taking notes.
So far, I have not been able to make the modified ossel hitch - the original hitch I posted - fail in surgical tubing. I have been able to get every other simpler knot I’ve tried to fail.
Another client of the “material matters” product ! 
While, of course, this is true, it should not drive us to the wild side, where anything goes, there are no knots but only “knotted materials”, there are no natural laws but only constructs of the human intellect, and we can not speak about anything - but we have to remain silent…There are many more things in knots that remain the same, that do not depend upon the specific circumstances and materials - and we can speak about knots, in general, because those things exist.
Having said that, I have to admit that if something is on the borders of the knotting world, this is a knot tied with/on this material. So, if you really wish to kill a knot tyer, to make him commit suicide, all you nedd is to present him a problem that should be solved with this material !
There was a thread where we tried to define what a rope and a knot is (1). I have to say that I, for one, have deliberately left knots tied on/with such materials outside the realm of definition - because I knew what strange animal is such an object… Imagine that the latex is replaced by a more elastic substance, and then by an even more elastic one…Where do we stop ? Will the objects constructed with the help of tangles made by this super-elastic tubular material bear any resemblance with a knot ? Are tangled elastic 2D toroidal membranes, following convoluted paths in 3D space, “knots”?
Why am I not surprised ? You would have had more success with boiled spaghetti, I guess.
( I am too old to start learning new tricks, with this material. I have decided to limit my involvement in the few brief moments the nurse ties my arm with this thing, to find the vein…
Fundamental questions…
Is OK to jam the knot?
Does surgical tubing jam well?
I think you mentioned the contraption is sometimes sent home with the customer with the knot in place. In that case, I’d want the knot to jam.
Xarax:
I certainly don’t want to burden this “Practical Knots” forum with tangential or inappropriate topics
The way I figure, this surgical tubing is in somewhat popular use, and people insist on bending it to various items in the course of their work. I’m interested in finding out how safely, easily and reliably they can accomplish their goals. Or, as the case may be, that they can’t make a reliable knot.
I want to know regarding this tubing - can it be knotted or otherwise made fast to something? If so, how?
After a bit of experimentation and thought, I found that the proposed hitch - the modified ossel - seems to hold quite securely (I’m still anxious to test it in bungee and watch it fail). Several of the other knots, put forth in this thread - the slipped modified buntline and gnat hitch and I’m sure others that I haven’t had the chance to test - have proven secure, although they were a bit awkward for me to tie.
Since surgical tubing seems to be a knottable (if a bit contrary) material, I think this is all a useful pursuit.
I intend to do some more testing with the knots proposed, and report back.
Is OK to jam the knot? Does surgical tubing jam well?I think you mentioned the contraption is sometimes sent home with the customer with the knot in place. In that case, I’d want the knot to jam.
It should not jam. A plain length of tubing about two meters long is sent home with the patient, and they are left to fend for themselves as they bend it to handrails, posts, and other household items as they set up their own space to do their exercises. Physical therapists also may tie the tubing in a patient’s home and leave it.
It shouldn’t jam, because sometimes it is only left for one exercise session, and then removed.
Surgical tubing may be difficult to untie at times, but the only way I’ve seen it actually jam is when it is wet and pulled up tight. Then it behaves a bit like monofilament. That’s one reason I’m trying to avoid knots that only work when pulled up wet. Almost any usually reliable knot will behave quite well in surgical tubing when you wet the tubing and pull it up tight. They just tend to jam.
If jamming is not a concern for someone knotting surgical tubing, wetting the knot and pulling it up quite tight seems to yield very reliable and secure knots.
Different application probably…
My memory is coming back to me now. I’ve had to use surgical tubing for physical therapy before.
I guess the knot here depends greatly on the exercise. Common exercises in tubing involve pulling a band with a foot or hand. In my physical therapy I had to do reverse calf raises to strengthen the muscles in front or my legs, like in the pic below.
In that case, I would jam a sling in the tubing for the patient, and then show them how to tie a Cow Hitch (and maybe even a Prusik) around an anchor. The Cow Hitch would obviously not jam for this application. I mention this because I often find myself overlooking simpler, more elegant solutions. Again, your applications are probably different (?).
I was considering this until he mentioned the issue of some hitches stretching away from the bar and allowing lengthwise rolling. Perhaps a Prusik or Klemheist would help reduce this tendency. The latter would be easier to make.
This approach would obviously halve the elasticity of the system, though.
As I’ve mentioned before, I’ve done and do strength training with rubber bands. I assume these rubber bands can take a lot heavier loading than medical tubing, and I’ve successfully used the Slipped Sheetbend for this task. Sheetbend is a very easy not to learn, easy to tie simple to tie, is easy to untie and has the slipped version for being untied even more easily, which is important when dealing with elastic materials.
I would also give a thumb up for Knot4us suggestion about the cow hitch. Easy to learn, hard to do wrong, quick and simple to tie and easy to untie.
The Fist Hitch as suggested in the original post, outperforms many of the suggested knots in the mentioned criteria, so it wouldn’t be a bad alternative at all. Tripling it around the object, would perhaps be a bad alternative if the patient was going to hitch it around a large object such as a tree trunk.
Come on ! We are DELIGHTED with your contribution ! I was trying to say that the “material matters” here a lot, much more than any other material we know. So we should consider those knots as altogether different from the knots we are used to tie , and do not attempt to impose solutions we already have for the common material, to problems generated in the world of a lengthwise elastic, AND tubular, AND sticky AND slippery material - but nobody can deny the practical nature of this knotting !
Please, do it ! When we listen about tests, this is music to our ears !
It would be great if you could possibly repeat any test you perform a reasonable number of times, so that the results can have a greater “statistical” significance.
Thank goodness someone has their eyes open and brain engaged!
Thank you, Barry!
This entire “O. knot / O. hitch” nonsense really irks me:
they are both hitches which are of course knots ,
and I’m skeptical that any of the parroting authors has
a solid basis for writing “ossel”. IIRC, Geoffrey didn’t find
good beginnings for it, but dug into some old languge for
a notion of why … .
More to the point of the OP, the ossel hitch is ill-suited
for other than like-sized/-diameter objects, as it needs close
fitting to nip the tail; relatively larger objects will result
in there being too much space where the tail is nipped.
The OP’s revision makes a full turn, so addresses this
aspect; unfortunately, what is lost, still, is the neat sort
of opposed-bights nipping that gives the Ossel such
staying-tied security.
To offer noose hitches and an eyeknot as alternatives strikes
me as missing the point of having the knot resist lateral
loads. This aspect could be addressed by putting on some
few round turns and then finishing with the noose-hitch
or even eyeknot.
One might try to employ the opposed-bights nipping by forming
the tail into a small timber hitch structure (dogging the
tail back around itself to form a small eye),
then wrap the line around the object once or more (and
over the tail, for added security,
then bring the line through the eye to reverse the direction
of wrapping, for one/two wraps, forming opposed bights at
this change of direction,
and finally work the SPart out through the opposed bights.
This will take some working to set --probably more so, with
surgical tubing, as you’ll want to put in some tension–,
but then it should nip, grip, and hold-tight pretty well.
The idea of setting some good stopper to make a line
that then becomes secure with other hitches is also
good --and simple! Or, as Knot4U suggests, making
a sling that then works surely w/simple knots.
Btw, have you tried the anchor bend , putting in
a 2nd tucked finish, and maybe an extra turn around
the object, for gripping?! I’d think that that would
do pretty well.
postscript:
Nice thing about Wikipedia is Editing --to wit:
The ossel hitch is a knot used to attach a rope or line to an object. It was originally used on Scottish gill nets to tie small line to larger rope that supported the net. Ossel is actually the Scottish word for "gill net" and for the line attaching the net to the float rope.[1][2]I rather doubted this.
Rather, the Ossel hitch works only on objects that are approximately the same diameter as the line, as the tail must be nipped under the initial turn, which if made on a larger object will have a gap between line and object. To what extent the true history of this knot can be learned is a matter of speculation; knots books are notoriously bad at accuracy! Examination of such "snood"/"gangion" hitches in commercial fishing in the present day will show that it is typical to tuck the hitching line (the snood) through the lay of the object line --which, yes, implies that braided lines aren't used here. In such cases, various simple hitches --e.g., the clove hitch, the ground line hitch-- can be used, with the tucked tail providing security of the knot against both loosening and shifting position along the line. (E.g., in some areas, lobster fishing is done with long ground lines to which numerous lobster pots are connected via approximately 10'-long snoods. It is possible that the ground line will at times be hauled up from different ends, so hitches might need to endure pulls from either direction. A ground line (sometimes referred to as a "trawl") might be a mile (!) long --impressive mountains of cordage when piled up on the dock or the deck of the trawler!
Interesting suggestion - and it would probably be also helpful, if it was accompanied ( at least…) with a photo - you know, the thing that was invented the other day, at 1826…(1)
Most of the cell phones have cameras nowadays, one does not really need to save money and buy a new Nikon.
If a simplified Klemheist works and prevents that lengthwise rolling/twisting problem, the elasticity of the system could be maintained by doing something similar to a Klemheist by first tying a permanent small loop, and then proceed to coil around the object as required and tuck the tubing through that permanent loop.
It’d be similar to what is sometimes called a tensionless hitch.
Thanks for the great input, Dan!
I’m a newbie, so please correct me if I’m wrong here. My intent is to contribute ideas, not ego.
I played with this, and I really don’t think much is lost with the round turn in the proposed hitch. When I think of an opposing bight nip, I think of something like Ashley’s bend, with that beautiful structure in the middle where both bights are fully loaded and form one of the best nips of any knot. The Ossel has a similar looking structure, but here one bight is active and one is passive. The active bight (the turn around the standing part) forms a good nip on the standing part and (more importantly, I think) nips the tail underneath. The bight formed by the tail just before it exits doesn’t seem to nip much at all, to me.
To demonstrate this, form an ossel hitch and haul the tail up just a bit, away from the standing part, enough to straighten it out so it doesn’t really form a bight. See if the nip is any less secure on the standing part or the tail. Without testing, all I have to go on is my imagination of the forces on the line, and how good it looks and feels when I give it a good tug. But it really doesn’t seem like the opposing bight in the tail end is doing much.
I think the final nip on the tail is what makes either knot secure, which is evidenced by the fact that the Ossel won’t hold fast on a larger object because that nip is compromised.
But I do I think the nip on the proposed hitch may be weaker than the Ossel’s nip, and here’s how:
If you form a Munter hitch, you essentially have an Ossel with just the first nip - the turn around the standing part. Clearly this is a good nip, or the Munter wouldn’t work. You can make a modified Munter analogous to my proposed hitch by adding a round turn. This added turn slightly decreases the tight nip of the Munter, and my intuition tells me this would lessen the effectiveness of the nip. I imagine you can test a Munter by putting a weight on the standing end, and seeing how much weight is needed on the tail to keep everything from slipping. I bet that just slightly more weight is needed on the tail to make the modified Munter with the round turn work.
That might not be the case, but if it is, then my proposed hitch (the Ossel with the round turn) may have a bit more force pulling the tail out from under the final nip than a plain Ossel.
Of course, this is all conjecture, and may not matter one bit in the security of the actual knots tied in some real line.
Bingo! --in that the loss comes mostly from any
relatively larger-diameter object rather than from
the different structure (the added turn). But look
at the basic ossel hitch tied around a small-dia.
object, and you’ll see how that turn around the SPart
is opposed by the “L” turn&tuck of the tail --that’s
what I’m pointing to. And, so, I have played around
with making the “L” sharper (“U”), and so on, and
to get the nipping effected independent of hitched
object!
Now, sparing another camera-click and special offload/upload,
at the moment,
I think words will suffice to my suggestion of effecting an
object-indepent opposed-bights nipping structure above.
We’ll work on a horizontally disposed object/cylinder,
from left to right.
With the tail, form a small eye, in a timber hitch manner,
turning the tail back over then tucked back under itself
(first crossing being over ensures the the nipped crossing
falls back more surely against the object!); this small eye
resided above (visually to our horizontal cylinder) & against
the cyclinder, dogged tail extending rightwards at the back.
Now, line flowing Top-Back-Down-Front-Up-…, as we’ve begun,
make a wrap (moving rightwards) around the cylinder and
cross over (further trapping/nipping) the tail; maybe "one good
turn deserves another? (YMMV on needed grip vs. lateral load);
and now on subsequent wrap,
as we bring SPart
(ah, yes, I assume a relatively short hitching line, and am tying
the knot backwards, so to speak --end->outwards! (which
shows a problem with the term “working end”, as I’m working
with the SPart-to-be, in another sense --of what has 100% load))
…
around from back, up … now INTO our small eye,
and U-turn back (forming, thus, our opposing bight to the eye’s)
and wrap Down-Back-Up…
with a little reach RIGHTwards, making subsequent wraps (just
1 or 2) from right-to-left --we’re aiming to bring the working
end (SPart) out through/between the opposed-bights.
These right-to-left wraps will be ones with greatest, SPart-delivered
tension, so it’s worth having a couple, if grip is needed (i.e., I think
these will pay greater gripping dividends than those put in from
the small eye; some bit of working can help, but naturally the
load will feed these last-formed wraps).
…
and, as indicated, wrap back leftwards as desired and bring the
SPart-end out between the opposed bights (which itself implies
that one cannot tie the knot with much tension, as one must
have looseness in order to make this exit tuck).
Now, one can try building tension (pre-stretching the rather
frictive elastic tubing) by working the left half (here) of small
eye & follow-on wraps tight, hauling out that turn through
the eye (SPart now in place) to tension wraps, then pulling
back sharply to pull into small eye; then it’s a matter of
working the right half’s wraps tight, with final pull on the
SPart, which should be well nipped, now.
IN SOME USUAL CORDAGE (not surgical tubing, which I suspect
is frictive, and of course highly elastic), less “working” will be
needed, and more will occur naturally via loading.
Btw, for a fun time of exploration, which might lead to some
workable solution, as well, try loading the ossel hitch
in reverse --pull the tail! You’ll see the new-tail
get nipped against the loaded end (new SPart); you might
endeavor to secure the tail in a way that fully forms an
opposing bight to this; add wraps at appropriate points
if lateral grip needs bolstering.
“Now, sparing another camera-click and special offload/upload, at the moment”
but not giving a dam about other people, who should try to decipher the tangle of words, and follow the mental picture as it is revealed, step by step…
Object-indepent opposed-bights nipping structure :
Gentlemen, we saved one camera click and one upload/download keybord key push…for the moment. And see what we have gained !
I’m not sure where you’re starting from here. Are you talking about appending this entire structure to the end of the fist hitch? Starting with that knot, and then taking the tail from that knot, and wrapping it around itself, timber-hitch style?
(first crossing being *over* ensures the the nipped crossing falls back more surely against the object!); this small eye resided above (visually to our horizontal cylinder) & against the cyclinder, dogged tail extending rightwards at the back.
I don’t think I’m following the description, as the way I’m doing it, passing over just collapses into passing under, but winding the opposite direction.
Now, line flowing Top-Back-Down-Front-Up-..., as we've begun, make a wrap (moving rightwards) around the cylinder and cross over (further trapping/nipping) the tail; maybe "one good turn deserves another? (YMMV on needed *grip* vs. lateral load); and now on subsequent wrap, as we bring SPart (ah, yes, I assume a relatively short hitching line, and am tying the knot *backwards*, so to speak --end->outwards! (which shows a problem with the term "working end", as I'm working with the SPart-to-be, in another sense --of what has 100% load)) ... around from back, up ... now INTO our small eye, and U-turn back (forming, thus, our opposing bight to the eye's) and wrap Down-Back-Up... with a little reach RIGHTwards, making subsequent wraps (just 1 or 2) from [u]right-to-left[/u] --we're aiming to bring the working end (SPart) out through/between the opposed-bights. These right-to-left wraps will be ones with greatest, SPart-delivered tension, so it's worth having a couple, if grip is needed (i.e., I think these will pay greater gripping dividends than those put in from the small eye; some bit of *working* can help, but naturally the load will feed these last-formed wraps). ... and, as indicated, wrap back leftwards as desired and bring the SPart-end out between the opposed bights (which itself implies that one cannot tie the knot with much tension, as one must have looseness in order to make this exit tuck).Now, one can try building tension (pre-stretching the rather
frictive elastic tubing) by working the left half (here) of small
eye & follow-on wraps tight, hauling out that turn through
the eye (SPart now in place) to tension wraps, then pulling
back sharply to pull into small eye; then it’s a matter of
working the right half’s wraps tight, with final pull on the
SPart, which should be well nipped, now.
Dan - I’d love to know what kind of complication you’ve devised, but I’m not good enough at following descriptions yet to reproduce what you’re describing. I’d love to see a picture of some kind if you were inclined to take or draw one.
Thanks for all the thought and input.
I’m starting --at the beginning, with the cylinder
disposed as described, horizontally, and working from just
at the top side of it, rightwards in progression.
[See bottommost prg., I think for maybe the quickest purchase
into what I’m describing.]
(first crossing being *over* ensures the the nipped crossing falls back more surely against the object!); this small eye resided above (visually to our horizontal cylinder) & against the cyclinder, dogged tail extending rightwards at the back.I don’t think I’m fllowing the description, as the way I’m doing it, passing over just collapses into passing under, but winding the opposite direction.
Now, line flowing Top-Back-Down-Front-Up-..., as we've begun, make a wrap (moving rightwards) around the cylinder and cross over (further trapping/nipping) the tail; ...Dan - I'd love to know what kind of complication you've devised, but I'm not good enough at following descriptions yet ...
I can’t buy this. It is a simple matter of wrapping a line
around a cylinder. I’ve specified direction --from the top
go back (away from viewer), down, towards viewer at
bottom, and up: this is obviously one direction of wrapping
–and moving rightwards.
And, so, coming back around on the right of the small eye,
one can wrap over its tail, in making a 2nd wrap.
At which point, for brevity, bring the SPart end THROUGH
the eye, and then turn (180deg) back down (as a Munter
turns in going around the SPart, say), and wrap now in
the reverse direction.
AND, let’s reverse both the wrapping-around and the
progression : so, reach a little removed to the right,
and bring wraps now LEFTwards, coming back to
the center (think of the wraps of a Prusik hitch
working towards the center SParts exit).
After 1-2(-3?) wraps --a matter of needed grip–,
you bring the SPart end out through the opposed
bights of the small-eye & turn through it.
And you’ll need to work surgical tubing into tightness.
SEEN IN REVERSE (for illustration purposes),
you would traverse the path of a Prusik hitch,
until making the crossing collar, where, once
to the center point of the ONE SPart you’ve
been following --your path into the knot, into one half-,
you’d turn down and wrap in reverse orientation to the
cylinder and away from center (so, continue leftwards,
if doing right half),
to finish by tying that small timber-hitch loop around
the SPart --and having a deuce of a time getting its
tail tucked under wraps. But this was for illustration.
At the most basic level --fewest wraps–,
I’m describing, NEARLY, the so-called “Killig hitch”,
except that IT takes a cow hitch tail and dogs it
around itself, WITHOUT that end turning around
the SPart (and so forming the nicely nipping opposed-bights
structure). The wraps specified above are for giving
lateral grip, and should be seen as easily added as
desired.
Dan -
I think I see where you’re going now. I hadn’t been working both sides back toward the center until you mentioned the prusik.
So do you mean like the attached image?
