Attatchment Knot Failure

Re: Bowline Instability

I don't keep harping on terminology for the sake of argument or to put anybody down. But no matter what profession we're in, language is our most important tool. And we can learn from each other across professional boundaries if we speak a common and precise language. And knots are universal.

Tom Dunlap surfs rock-climbing and rope rescue sites to expand his knowledge, and I've learned more new rope technique from arborist sites than I've learned anywhere else.

My point is valid, though: I've seen at least three different knots refered to as a "double fisherman's" on arborist sites. Others can't possibly know what is meant by that term if it has multiple meanings.

But everyone who uses knots should know what an overhand knot is, and they should (hopefully) know what a double overhand is. All the knots called "double fisherman's" are some variation of the double overhand, but one is a bend, one is a noose, and one is a simple knot (typically used as a stopper or backup knot). So why not call them what they are?

And if I'm a "punk", then I guess a punk can be 52 years old and a widely recognized and published specialist in rope technique.

</font><blockquote><font class="small">In reply to:</font><hr />
I have never heard, seen etc, anybody go tie a bowline in their rope and tie their clip in to the tail of the knot.

[/ QUOTE ]
Nobody's talking about tying the load to the tail. But if the tail gets jerked because it catches on something, it can cause the knot to invert and come apart.

</font><blockquote><font class="small">In reply to:</font><hr />
the way that the knot is used in this profesion, especially as a termination knot, is not the same as for whatever back ground you seem to have. Tied to a clip, it will not be jerked from the tail

[/ QUOTE ]
A bowline is the same knot no matter what "profession" it's used in. It can collapse not just by a pull on the tail, but also if the loop (rabbit hole) around the bight gets caught on descent. If so, it will invert and slip apart in a milisecond and dump it's load.

- Robert
 
Avert,

1. You are forgetting the original purpose of this thread, which is a termination knot failing.

2. If you look at my original posts. Using common arborist terminology, backed up by clear photos. An arborist would see crystal clear exactly what I'm referring to. If I am able to communicate exactly what I intended, then I've succeeded.

3. You are dead wrong on what a backup is. A backup knot is an independent knot tied in addition to the primary knot. A backup knot's mission is to be there in the unlikely failure of the primary knot. Further in the context of this thread. I maintain that if the climber had of used a backup knot in addition to his primary attachment knot that failed. The climber would probably would not have fell.

4. You have succeed in insulting everyone that has taught me that you should always use a backup knot in addition to your primary knot. An exception is a termination knot that you can set properly in advance and dress ends with small nylon cord. Photo's posted earlier in this thread, clearly show a triple fisherman terminated into a split tail.

5. I've read you other posts and realize you have a lot to offer. But you need to get over yourself. My mission is to learn from others, so I don't make a major mistake that could cost me dearly.

You don't convert people by insulting them.
 
</font><blockquote><font class="small">In reply to:</font><hr />
046: You don't convert people by insulting them.

[/ QUOTE ] First, I've said nothing that should have been taken as an insult. Second, I'm not here to convert anyone but to educate those who are willing to acknowledge that they have something to learn. Those who feel they already know will likely take offense at the suggestion that they may not.

</font><blockquote><font class="small">In reply to:</font><hr />
1. You are forgetting the original purpose of this thread, which is a termination knot failing.

[/ QUOTE ]Not at all. I'm trying to share the principles of knot tying so that practitioners can make educated judgements about what is necessary for safety. Those who don't care to know the principles can use "rules of thumb" which often use the words "always" and "never" and eliminate the need to think for oneself in sometimes stressful environments.

In most rigging disciplines where national standards apply, there are three levels of knowledge and practice:
- awareness: introductory knowledge and skills - these people are minimally oriented to the field
- operations: can function semi-independently under guidance - these people understand rules of thumb
- technician: can function independently in all skills - these people understand principles to make judgements

</font><blockquote><font class="small">In reply to:</font><hr />
If I am able to communicate exactly what I intended, then I've succeeded.

[/ QUOTE ]Yes, if your only goal is communication. As I will continue to emphasize (and professionals in every field will agree), using correct terminology (as well as technique) separates the general practitioners from the true professionals.

</font><blockquote><font class="small">In reply to:</font><hr />
You are dead wrong on what a backup is. A backup knot is an independent knot tied in addition to the primary knot.

[/ QUOTE ]This is an interesting statement from someone who acknowledges that he is a student of many teachers, while I make part of my living teaching knots and rigging to practitioners in a variety of rope disciplines.

What you're talking about is redundancy in the event of a primary knot failure. In many critical applications, this is wise. If a redundant knot makes you feel more secure and it does not interfere with the primary knot function, there's nothing wrong with it. But that's not the purpose of a backup knot, which is to prevent an insecure or unstable knot from coming apart (e.g. bowline or sheetbend).

Also interesting that the pictures you posted support this contention. You show a very secure triple overhand noose with the tail nicely whipped. The whipping is an excellent method to permanently secure the tail without interfering with function, but it is not a redundant backup in the way you describe - for no one in his right mind would hang on an eye formed only by whipping with thread.

Your pictures also show a beautifully tied, dressed, and set figure-8-on-a-bight which cannot possibly come undone and needs no backup at all but which is now excessively long which can interfere with function. If you're going to back up a figure-8, the secondary knot should be snugged up against the primary knot so that no tail slippage is possible and so that the knot has as little "gain" (length) as possible.

Your pictures also show a regular bowline and a yosemite bowline backed up with double overhands. This would be wise with the bowline, since it's a "cowboy" bowline with the tail left outside the finished loop, which increases the likelihood of it catching and inverting the knot.

However, with both bowlines, the tail is left excessively long, the backup knot is not snug to the primary knot, and is likely to interfere with function.

- Robert
 
Hi Folks,
I'm also not replying to anyone in particular.
My father climbed for 40 years with a bowline as his attachment knot(and non locking carabinas)never failed once?
The original set up for climbing always had a backup on the bowline."The prusik" The bowline was used as a midline knot and not a termination there by making it impossible to fail.(prusik would always fail first)

When people started changing to a separate prusik or split tail and not making the prusik from the end of the rope the problem began.
They took the attachment knot they had been using for years and carried on tying it as there attachment point but now turning it into a termination.This has then been passed down over the years as the termination knot of arborists.

Throw in to the equation modern 16-strand which by its shape and tighter weave doesn't mate the surfaces of the rope together as well as the softer multi-plait for example and you have a real problem. We use the latest gear in the industry these days so why are we still using old terminations. There are better knots than the bowline.Leave it for pulling cars out of the ditch and applications where you want to undo it when you have loaded it with 2 ton,and use something else on our life line maybe (dare I say it a splice)


The safety equipment of today promotes complaisantancy it shouldn't but it does.It was invented because of the complaisant."Oh it can't fail"
"Click it and forget it" so to speak.If we don't think about whether or not our carabinas are going to come open why would we think to check our termination regularly,Being slightly paronoid about our gear keeps us a live..Only death is a 100% certain.So let it be from old age and not from "terminations"


Didj
 
</font><blockquote><font class="small">In reply to:</font><hr />
They took the attachment knot they had been using for years and carried on tying it as there attachment point but now turning it into a termination.

[/ QUOTE ]

This is a good point (and the history is interesting).

One of the common applications of the bowline in rope rescue is the connection of the mainline and belay line to a litter bridle for a lower or raise. In this case, the two lines are interlaced at the bowlines, which are then both clipped into the focal point of the litter bridle. But these are "long-tailed" bowlines, with 8-12' tails which are terminated in figure-8s on a bight for the safeties for the litter attendant and the patient.

So, like the ascending knot acting as the "backup" for the bowline in the old DdRT, the safety tie-ins are the backup for the interlaced long-tail bowlines used in litter rigging. No other backup is necessary in each of these cases.

This image shows the knots tied loosely for clarity, but the bowlines would have very small fixed loops and, of course, would be well dressed and set (as would be the figure 8s):

High-Angle_Litter_Rigging.jpg


- Robert
 
Rescueman, Your gripe about the use of "double fisherman's" for knots that are not the double fisherman's line joining knot is valid. FYI, the double overhand knot tied back on the standing line to form a noose has a proper name. It is the Scaffold knot. It is difficult but it would really help if we could all get on the same page terminologically.
 
can we get one thing straight here..........the knot in kepsons tree climbers companion that he refers to as the double fishermans loop....is it?
 
Tim is right A scaffold knot also known as a slipped triple overhand,Triple overhand noose and a triple fishermans has three turns.Its used most for tying on hooks.Double fishermans or double overhand noose,slipped double overhand,The knot we are talking about is known by all these names.No one is right or wrong here. Its a shame we don't have latin names for knots then maybe we could all talk the same language.After all a Sycamore in the States isn't a Sycamore in Europe....

Knots had always been passed down by demonstration before the knot Guild was formed so it is no wonder that there are so many names for the same knot

Didj
 
Re: so many names

</font><blockquote><font class="small">In reply to:</font><hr />
Knots had always been passed down by demonstration before the knot Guild was formed so it is no wonder that there are so many names for the same knot

[/ QUOTE ]
I think it's wonderful that there's different names for each knot - the more names one knows the more knot literate one is and the more one can communicate with others.

The square knot is the reef knot. The figure-8 bend is the Flemish bend. The sheet bend is the Weaver's knot or Becket bend. Ring bend is a water knot. Girth hitch is a lark's foot. The double fisherman's bend is the grapevine.

My problem is using one name for a multitude of variant knots - this is what confounds communication - which of those variants is one refering to? Is a double fisherman's the bend, the noose, or the stopper? Since all double fisherman knots are variants of the double overhand and since they are differentiated by their function (bend, noose, stopper/backup), then why not follow Ockham's Razor and use the simplest name? For instance, how many people would be confused by the term Flemish bend but would immediately know how to tie a figure-8 bend? The term "overhand" is the common denominator, double describes the number of turns, and the functional term finishes the name. Can't be more straightforward than that!

The scaffold knot is generally described as a triple overhand noose, used by "some flathead fishermen" to tie off a hook:

scaffold.gif


Oh, the knot Jepson describes as a "fisherman's loop" is clearly a noose. A loop knot, like a butterfly or bowline, creates a fixed-dimension loop. A noose knot, like the scaffold, hangman's, or lariat, creates a loop that cinches when the standing part is pulled or the loop is loaded.

- Robert
 
Mark, got a pic of that new knot you learned in TX? In response to stevebullman and 046, have you ever heard of a professional splice failing? This would be the place to discuss it but I don't think it happens. Also, can we try to keep the bickering to a minimum? I respect everyones opinion on this forum, input of any kind is great but if you want to squabble maybe you should meet at a pub.
 
Hey Raven,

I HAVE heard of a pro-spliced split-tail failing. It was probably 4 years or so ago. Someone had ordered a spliced 1/2 inch for a split-tail blake system and the splice came out while the guy was climbing. He ended up a bit "damaged" and sued the crud out of the manufacturer. I heard about it while I was working for Davey up in CO Springs, CO but have no idea where it happened or who the guy worked for. I remember that the guy had ordered the spliced tail through a catalogue, but I don't know which one either. It's been a while now... I haven't used a splice since then.
 
Raven,

I will try to get a photo (when I remember "exactly" how it was tied.

I just heard of a splice pulling out with only a climber leaning into a new line. Scary. They told me that they called the retailer and they only had one left. The person in the store tried to pull the splice out and it fell apart too! GEEEZ!
 
At a company I used to work for, one of my coworkers had a splice fail. It was a factory splice on a split tail. This was one of the turning points for me. Reading that incident report convinced me that I should be doing my own splices and doing them right.

love
nick
 
I've waited for some time to pass before posting. I almost didn't bother coming back.

The original topic of this thread is "Attachment knot failure" before it got hijacked into what is the proper names for knots and that we are all wrong for using common arborist terminology.

Even though my posts are crystal clear what knot I'm refering to. Complete with clear photo's showing exactly what I intended. We get a lashing about what fools we are for using the wrong terms.

The point of this thread is to prevent further accidents from happening due to attachment knot failure. If the climber in question had terminated his life line with the correct attachment knot with a backup each and everytime. The attachment knot would not have failed period!

I see referances for termination knots in Arborist catalogs I would never use. I prefer a figure eight with a double fisherman as a backup for my lifeline. For permenant terminations I use a triple fisherman, possibly the most secure bend known. How someone can find fault with these is beyond me.

Thanks for reading,
 
At the ANSI Z133 meeting in October the climbing sub-committee will be discussing rope termination hitches. There has been rumblings to not allow knots or hitches, only splices. Those of us who still have a use for a rope and saddle have put the stink on that idea. What rubbish!

What hitches or rope configurations are people using? My preference is the double fisherman's loop [or whatever you care to call it]. There are limitations to most terminations. Do we "dumb-down" the regs for the few who don't inspect their equipment?
 
Hey Tom,

Im still useing the bowline w/o any back up. I will never be convinced this can/will fail until someone personally shows me how. Sure I know how to tie the dble fish, but I HAVE seen one of these come untied, in a tree, while tied to a climber. Fortunately it was only on a lanyard and he was tied in w/ his rope, but it still scared the crap out of both of us.

As for the ANSI committee, who is on this committee and how can we get a holdof these members to express our feelings on the issue? Also, which one of them is going to make the stand that an eye splice is 100% safe? Ive seen discussions of splices coming undone. And if I splice a rope and sell it, I in turn take a large amount of liability in the future safety of the user. If I dont make that splice and the user ties a knot (hitch...whatever), which fails, I could not reasonably be held in that liability.

I dont think we need to dumb down the regs for those who dont inspect. However, the loved ones of such people need to realize that because of laziness, accidents happend and manufacturers are not to blame. If the regs are there and not followed, thats the climbers fault. Ansi can make their regs to read should or shall, but what they SHOULD do is simply get the word out on safety. Things such as splices should be simply recomendations based on safety ratings/lack of strength on rope, therefore not a requirment to splice. ANSI can hold more meetings or attend chapter conferences and speak on new issues. Hand out FREE ansi standards.

ANSI makes the 'spliced only' requirement, ITCC MC contestant gets his rope splice stuck in a crotch on retrieval, looses MC. Is ANSI going to buy the guy the gear he lost out on by taking 4th instead of 1st? Doubt it.
 
Re: Attachment Knot Failure

I won't name names about who broached the idea of having only splices. I will tell you that Don Blair is the chair of the climbing sub-group. Right now I'm not exactly sure who else is on the committee. Suffice it to say, there are no techocrats or bureaucrats. All of the members are quite close to climbing. Maybe not every day climbers but close enough to fully understand the ups and downs of production climbing.

If there are concerns or suggestions, please use this forum as a place to share what's on your mind. Believe me, the committees don't want to make things bad or hard for the industry. The goal is to have workable standards. If we don't mind the house, OSHA is too likely to come in and set standards. Better to do this from inside the industry.

My new employer, Swingle Tree Care has given me the support to join the TCIA Safety Committee. This will keep me in touch with future trends and get me to the ANSI meetings too.
 
Re: Attachment Knot Failure

Tom,

I'm in that loop on the email list and have made a couple of comments. The one that means the most to me is to have a minimum length for tails (for attachment knot terminations) determined. I like the 4-1 rule for them. Any thoughs about that? I've seen too many tails tied that are almost ready to pull into the knot. We've made more climbers change that item at competition inspections than anything else.
 
Re: Attachment Knot Failure

I like the idea of the Splices Only rule /forum/images/graemlins/bling.gif

Seriously though, that's a silly idea. Frankly, it's hard for some people to get their hands on a spliced rope. It can be made possible, but can be tough for some of those living in the boon-docks. Some people are just freaked out by splices, I guess because you can't "see" what's going on. They should not be forced to rely on equipment they are not comfortable with.

Maybe there should be a splicer on that committee. I am in Southern CA now, where do I sign up?

love
nick
 
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