Author Topic: Challenge: Breakaway Neck Lanyard  (Read 35319 times)

knot4u

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Challenge: Breakaway Neck Lanyard
« on: August 05, 2011, 04:46:58 AM »
Design a neck lanyard with paracord (or similar) having a breakaway knot that's relatively simple and elegant.  The breakaway knot is intended to be a safety feature to prevent injury or strangulation (e.g., if the lanyard gets caught in a machine, or if the lanyard gets caught on a tree branch, etc.).

The breakaway...
  • allows the lanyard to stay put under normal conditions.
  • comes apart at the knot when a substantially higher forced is applied.
  • does NOT have to be pure rope (e.g., elegant integration of a keyring or other common device is acceptable).
  • must not take forever to untie and retie when the user changes items on the lanyard (e.g., a whipping connection is probably unacceptable).
 

EDIT: See my current setup here: http://igkt.net/sm/index.php?topic=3432.msg24165#msg24165
« Last Edit: October 05, 2012, 01:45:52 AM by knot4u »

KnotMe

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Re: Challenge: Breakaway Neck Lanyard
« Reply #1 on: August 05, 2011, 06:47:41 AM »
This is an excerpt from a... monograph?  workbook?  booklet?  that I'm working on.  I've posted about it on this forum before, but...

http://www.chineseknotting.org/overhand/gallery/overhand-safety-excerpt.pdf

Sweeney

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Re: Challenge: Breakaway Neck Lanyard
« Reply #2 on: August 05, 2011, 09:28:50 AM »
I've used lanyard "breakaways" - 2 small plastic cones which snap together. They have a hole through each end so after threading the cord, overhand knots act as stoppers (buried within the fitting when closed) - these will take cord up to about 2mm but no thicker and are easily re-attached if they come apart. Paracord can be attached to thinner pieces at the fitting without looking too clumsy - in effect the plastic bit replaces the weak thread in the example shown in KnotMe's paper.

Barry
« Last Edit: August 05, 2011, 01:17:54 PM by Sweeney »

Andre

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Re: Challenge: Breakaway Neck Lanyard
« Reply #3 on: August 05, 2011, 03:10:04 PM »
This is an excerpt from a... monograph?  workbook?  booklet?  that I'm working on.  I've posted about it on this forum before, but...

http://www.chineseknotting.org/overhand/gallery/overhand-safety-excerpt.pdf


I like this solution very much.

I have used in the past what I call a "wrong" fisherman's with the two overhands apposed on the opposite side, so that the ends will just slide out when under tension.

Andre

KnotMe

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Re: Challenge: Breakaway Neck Lanyard
« Reply #4 on: August 06, 2011, 06:40:12 PM »
you will find that over time, the key rings will discolour your paracord.  this may or may not matter to you, after all it's not like you don't have more paracord.  8)
the rings may also abrade the fibres of your cord, but in this situation, it's certainly not critical.

out of curiosity, what have you got there?  flashlight, whistle, firesteel, ...  other side of firesteel?

KnotMe

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Re: Challenge: Breakaway Neck Lanyard
« Reply #5 on: August 07, 2011, 09:34:41 PM »
The breakaway is an O-ring, instead of a metal keyring.  I'm guessing that O-ring breaks somewhere between 10 - 20 pounds.  Extra O-rings are attached to replace a broken O-ring, or to increase the break strength if desired.
you've got lots.  don't guess.  try one to failure.  report back.  8)

Sweeney

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Re: Challenge: Breakaway Neck Lanyard
« Reply #6 on: August 15, 2011, 08:43:28 AM »
I came across this video by accident - the friction within the square knot finish might be enough to provide a breakaway? http://www.youtube.com/watch?v=ZdrV3T7dIIA&feature=related

Barry


rusco7614

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Re: Challenge: Breakaway Neck Lanyard
« Reply #7 on: April 14, 2012, 12:27:19 PM »
Only just found this thread, and the link to video is no longer working, so don't know if this option has been covered.

This was a breakaway lanyard idea I played around with a while ago, using a single fishermans knot as a low-friction connection.


Completed lanyard on a flashlight. Neck loop can be easily shortened using a simple chain plait to form a fob when not required.


Breakaway knot showing formation. Working end of the small loop forms the fisherman's knot.


Breakaway knot - tightened.


Under excessive tension, the end of neck loop simply pulls out of fisherman's knot. The smaller loop remains intact, so multiple items on it would not be lost.

I liked this arrangement, as there was no uncomfortable knot at the back of your neck, and the whole thing is very simple and neat. However, this arrangement only seems effective if tied in fairly solid climbing accessory cord. In my experiments, softer cordage (such as 550 paracord) does not appear to 'breakaway' as the bulkier sealed (melted) end of the cord jams in the fisherman's. I guess it may work if you left the breakaway end unsealed, but it would obviously then fray and look messy, and make retying difficult.

Russ

knot4u

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Re: Challenge: Breakaway Neck Lanyard
« Reply #8 on: April 14, 2012, 05:02:43 PM »
Thank you for reviving this thread. On a survival forum, the users explained to me that the breakaway should be at the back of the neck for maximum safety.

The main reason for the breakaway is to save you when your gear and lanyard get wrapped in a machine or whatever. If the breakaway is down at your gear, then you can instantly be in serious danger. The machine and the lanyard (probably 550 paracord) can easily form a strong loop around your neck. Another scenario is you're in a struggle with somebody, and they grab your lanyard and gear. If your breakaway is down by your gear, then you have provided the assailant with a convenient way to have control over your head and neck, and thus your body.

Those are two major reasons I went through the trouble of making a breakaway in the first place. Here's an idea of improvements I made...



By the way, I have not found an acceptable all rope solution. When I really need the breakaway, it is going to be a life-or-death situation. I need a breakaway that is absolutely going to work 100% of the time, not a breakaway that will probably work if set correctly.
« Last Edit: April 14, 2012, 06:22:28 PM by knot4u »

rusco7614

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Re: Challenge: Breakaway Neck Lanyard
« Reply #9 on: April 14, 2012, 06:58:31 PM »
Yep - the single fishermans isn't perfect.

The option I'm using with 550 cord at the moment is a simple cordlock (as often used on clothing, backpacks, etc), which seems to work really well, and allows very easy adjustment of the size of the neck loop as well.


Breakaway - and ajustable - lanyard on a flashlight.

Russ

Sweeney

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Re: Challenge: Breakaway Neck Lanyard
« Reply #10 on: April 15, 2012, 08:19:42 AM »
I've started using cat collar breakaways (all cat collars have them of one sort or another). They are a small version of the usual squeeze-the-sides-to-open buckle but the prongs are rounded at the side so a sharp tug and the buckle opens (it can also be opened by squeezing the sides as usual). I find that these take quite a pull to break open (it hurts!) but they are not resistant enough to do real harm.

Barry

rusco7614

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Re: Challenge: Breakaway Neck Lanyard
« Reply #11 on: April 15, 2012, 01:50:10 PM »
I found some o-rings at home last night, so had a play with the aim of finding a neater way of integrating one into a 550-cord lanyard. Pics aren't great, but how about a couple of double sheet bends, like this:


O-ring breakaway with double sheet bends.


Other side.

Russ

Sweeney

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Re: Challenge: Breakaway Neck Lanyard
« Reply #12 on: April 15, 2012, 05:12:16 PM »
I can't lay a hand on an o-ring just now but a Simple Simon Under might look better as the ends run along the standing parts see
http://en.wikipedia.org/wiki/Simple_Simon_under.

Barry

knot4u

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Re: Challenge: Breakaway Neck Lanyard
« Reply #13 on: April 15, 2012, 07:20:53 PM »
I like the idea of the Sheet Bend/Simple Simon with the O-rings.

These overhand slip knots below are not that difficult to untie, and I barely feel them on my neck.

« Last Edit: April 15, 2012, 07:37:14 PM by knot4u »

Sweeney

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Re: Challenge: Breakaway Neck Lanyard
« Reply #14 on: April 15, 2012, 09:35:58 PM »
Does anyone know how much force it takes to break one of these O rings?

Barry

 

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