Author Topic: Backflip Double Bowline - a secure variant I have not seen presented before  (Read 2733 times)

erizo1

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I have been playing with bowline variants, and I'm interested in the various methods of "locking" or otherwise adding to the security of the standard bowline. After reading Mark Gommers's paper (http://www.paci.com.au/downloads_public/knots/Bowlines_Analysis.pdf), I'd like to propose this addition to the double bowline. (Of course, please let me know if this has been suggested before.) In my head while I've been playing with it I've been calling it a Backflip Double Bowline because of the way the working end wraps around the back of the two turns of the nipping loop to pass down through them again.

It's somewhat similar to the knot labeled in the above paper "Lee's locked bowline," and a comparison to it illustrates why I think this knot has a security advantage. With Lee's locked bowline, the Yosemite finish is applied, and then the working end is tucked back down through both the nipping loop and the Yosemite turn around the leg of the eye. In a manner of speaking, this essentially adds two locks (Yosemite finish and then additional tuck) to a standard bowline.

The knot shown below starts with a more secure form of the bowline to begin with. Then the working end is further locked by being passed through the double nipping loop a second time. So this knot makes use of the added security of the double bowline twice, once in the "base" knot and then again in the lock applied.

The resulting form of the knot looks almost identical to Lee's locked bowline and produces a neat and compact knot that seems - in my limited tinkering - to be stable, resistant to ring loading, and easy to untie. I need to do more testing with heavier loads and in different ropes. The knot is shown below tied in 550 paracord.

I'd be grateful for your comments.
« Last Edit: October 01, 2015, 03:55:35 PM by erizo1 »

erizo1

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I've just realized that this knot is also very similar to the End-Bound Double Bowline. The difference is in the path the working end takes after it goes through the nipping loops for the first time:
  • backflip double bowline - back up between the two sides of the collar
  • EBDB - around the nipping turns outside the collar
« Last Edit: October 01, 2015, 04:10:24 PM by erizo1 »

alanleeknots

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Hi erizo1,  Here is the same knots have presented by knoeud at Reply #81   http://igkt.net/sm/index.php?topic=4480.75.

                謝謝  alan lee

                also check this link at reply #64 http://igkt.net/sm/index.php?topic=19.60
« Last Edit: October 01, 2015, 08:35:51 PM by eric22 »

Dan_Lehman

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I've just realized that this knot is also very similar to the End-Bound Double Bowline.
Yes, and the EBDB is designed so that "back flip"
turn grips the S.Part to prevent it from loosening.
It does this pretty well if set well,
but I did find a springy polypropylene laid cord
in which, after a moment's holding, all the turns
just loosened (!).  (I cursed at it a while, but that
didn't help.)  ;D


--dl*
====

erizo1

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Thanks, Alan. Any idea what "RDB" stands for? I guess it's _____ double bowline, but I couldn't see what "R" would refer to from that post.

Dan, I see what you mean about the advantage in the EBDB of having the standing part also encircled by the "backflip" turn. I had not played much with the EBDB, but I'm very impressed with how solid it seems. It seems like all the parts work together to interlock - every part that grips a section of the knot is itself gripped by another section.

Thanks for your replies!

alanleeknots

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Hi All,
          erizo1, according to this two links  Reply #81   http://igkt.net/sm/index.php?topic=4480.75.
                                                            Reply #64 http://igkt.net/sm/index.php?topic=19.60
         
          Seem like DDk first introduce this simple lock to this forum, and knoeud  apply it to the Double Bowline.
          I have no idea why is "RBD"  ?
             謝謝  alan lee
« Last Edit: October 02, 2015, 08:00:25 PM by eric22 »

alpineer

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Any idea what "RDB" stands for?

Probably Roundturn Double Bowline.