How to Join Three Lengths of Cord ?

[xarax]

   ( I used Roger E. Miles subtitle -with a question mark- on purpose, to indicate that we should better look for symmetric end-to-end-to-end knots, 3 ends- or 3 lines- symmetric bends. )

   Suppose you would like to join three lines together, joining one end of each line with one end of the other two lines. What are you going to do ?
   Many people would probably claim that this is a rare situation, which never appeared as a practical problem to them. Well, I have not posted this question in the "Practical knots" section ... although I believe it appears in more occasions than we think.
   (My original problem was to generalize the Zeppelin bend in the case of 3 lines, but I decided to present the more general question instead.)

[SS369]

Hello xarax,

one application of this idea is usually decorative and I use a three strand Matthew Walker knot.

But for simple practical usage I generally go the easiest route and just bundle the three lines and tie an overhand with them all. The paths are not whatever the equivalent to parallel but it gets the work done.

Then you could also bend them using interlocked loop knots, e.g., bowlines, etc.

Not sure about symmetry, although the knots should all have the same value. I think since all three lines are doing the the same it can qualify.

SS

[xarax]

   Thank you SS369,

   If one wishes a "lanyard" knot,  the 3-strand Mathew Walker knot and the 3 line-overhand ( 3-line Water knot) are fine, of course. However, although they are symmetric in a broader sense ( each rope path inside the knot s nub is similar to each and every other), they are not as symmetric as they could possibly be. I would prefer a knot where each of the the 6 ends leave the knot along 3 perpendicular axes. The 3-interlinked loop knots would also be a practical solution, but the total consumption of rope length would make the knot bulky and unnecessarily convoluted. There is not any "economy of scale" we would be waiting for, in such a solution that incorporates three independent fixed loops, that happen to be interlinked together at their tips.
   Starting from a relevant thread in this Forum a few time ago, I tried to think of all the bends I know that could serve as knots for a net. And then I thought, what happens if this net is not a planar, but a space, a 3D net, i.e. the knots are meant to lie at the lattice points of a 3D orthogonal lattice ?
   

[SS369]

Hi xarax.

Some of this can depend on what the use/loadings will be. Will there be equal tension? Are we talking about the using of the six ends to load or just three lines, end connected, non-planar?

And let's throw in another complexity, laid rope or braided?
With laid rope you could just weave through the lays and sort of be non-knotted, as in a cargo net.

I have just tried in small diameter cord, three interlinked overhands - Zeppelin style knot and although it work (as best I can stress it) it just does not look all that great.

Aesthetically, the lanyard type knot looks to be more force balanced. So far.  ;-)

SS

[xarax]

Will there be equal tension?

No, I think that would be too restrictive...

Are we talking about the using of the six ends to load or just three lines

For a 3D net, all ends could be loaded, individually or simultaneously. For a end-to-end-to-end knot, we have 3 standing ends and 3 tails. We should investigate both cases, I guess, and see if the first can also serve the second.

quote author=SS369 link=topic=3765.msg21975#msg21975 date=1328032110]
With laid rope you could just weave through the lays and sort of be non-knotted, as in a cargo net.[/quote]

If you were trying to catch 4D fishes with a 3D net, that would not be such an elegant solution !  We want point-like knots, not weaved lines.

 

three interlinked overhands - Zeppelin style knot

I do not really know which is the equivalent of the Zeppelin knot in the case of 3 lines...(That was my original - less general - question) . The description of "three interlinked overhands" is not enough, I am afraid...

[roo]

   ( I used Roger E. Miles subtitle -with a question mark- on purpose, to indicate that we should better look for symmetric end-to-end-to-end knots, 3 ends- or 3 lines- symmetric bends. )

   Suppose you would like to join three lines together, joining one end of each line with one end of the other two lines. What are you going to do ?
   Many people would probably claim that this is a rare situation, which never appeared as a practical problem to them. Well, I have not posted this question in the "Practical knots" section ... although I believe it appears in more occasions than we think.
   (My original problem was to generalize the Zeppelin bend in the case of 3 lines, but I decided to present the more general question instead.)

I think there may be some advantage in using a previously discussed approach using interlinked loops:
http://igkt.net/sm/index.php?topic=2012.msg14186#msg14186

The number of variables involved with three lines of different sizes, materials, and loading profiles interacting is going to cause considerable hesitation when trying to assess how these variables might sabotage a single knot form.

You might experiment with a Sheet Bend form where the thickest line assumes the "U" part and the two thinner lines assume the "p" or "q" part.

http://notableknotindex.webs.com/midspan.html

Such an approach might be successful in other bends, too, at the expense of some messy bulk.