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Brian in SLC
04-17-2012, 02:32 PM
The back up webbing to a pretty ruff looking blue piece was tied in an overhand knot, not a water knot. Sometimes its easy to look at the triangle shape of the knot and think its ok. The key is to look at the tag ends of the knot. Two tag ends coming out the same side = overhand and wrong.

Hmmm. I've rapped of an in-line overhand a number of times. Everytime I connect to ropes together for example.

Have used to to tie cord together for a rap anchor, mostly 'cause I had minimal amount of cord and was in a hurry (v-thread for an ice anchor and my stance was poor).

I normally use a water knot. Still...an in-line overhand (aka "flat overhand") should work ok, I'd think....only thing I'd be worried about is how easy it could come untied, which, is why I use them especially to tie two rappel lines together.

Tom, Hank, what say ye?

ratagonia
04-17-2012, 03:27 PM
Hmmm. I've rapped of an in-line overhand a number of times. Everytime I connect to ropes together for example.

Have used to to tie cord together for a rap anchor, mostly 'cause I had minimal amount of cord and was in a hurry (v-thread for an ice anchor and my stance was poor).

I normally use a water knot. Still...an in-line overhand (aka "flat overhand") should work ok, I'd think....only thing I'd be worried about is how easy it could come untied, which, is why I use them especially to tie two rappel lines together.

Tom, Hank, what say ye?

Hank and I have discussed. We know the EDK / offset overhand bend works in ROPE, but we do not know if it works on webbing. Rope and webbing have significantly different properties. Therefore, we reached the conclusion we can recommend it for rope, and recommend AGAINST it for webbing. We just don't know, and can make a case for it working itself open in the more-slippery webbing. We hope to get it on a testing machine sometime soon.

Tom

Brian in SLC
04-18-2012, 08:43 AM
We know the EDK / offset overhand bend works in ROPE, but we do not know if it works on webbing. Rope and webbing have significantly different properties. Therefore, we reached the conclusion we can recommend it for rope, and recommend AGAINST it for webbing. We just don't know, and can make a case for it working itself open in the more-slippery webbing. We hope to get it on a testing machine sometime soon.

Report results when you get them!

Quick search pulls up the Moyer data, and, one of the tests he did was to test 1" tubular webbing with a flat figure eight. Didn't capsize/roll, failed at the knot at 2070lbf. Interesting.

I'll admit I like the EDK for how simple and quick it is. Fairly sure I've rappelled from a sling, webbing, with an EDK knot securing the ends. I know for a route I was doing, I had some slings pre-tied that way to be able to quickly deploy them 'cause that knot is so easy to undo. Yeah, YMMV.

That water knot is fine, but, when you're tired, in a cramped position, trying to tie the knot, feed the other end through and around, tension it.... So much easier to match the ends, whip in an overhand, tension, good to go. Simple, easy to inspect.

Wasn't there a fairly good train wreck (accident) not too long ago where folks blew the water knot in the anchor webbing and it pulled loose? Seem to recall.

Yeah, I wouldn't carry a knotted sling for climbing/canyoning use as an anchor sling with an EDK in it (ok, I have, but not normally), but...if I was cutting a long sling into anchor material...I dunno.

Report results!

Thanks.

ratagonia
04-18-2012, 08:52 AM
Report results when you get them!

Quick search pulls up the Moyer data, and, one of the tests he did was to test 1" tubular webbing with a flat figure eight. Didn't capsize/roll, failed at the knot at 2070lbf. Interesting.

I'll admit I like the EDK for how simple and quick it is. Fairly sure I've rappelled from a sling, webbing, with an EDK knot securing the ends. I know for a route I was doing, I had some slings pre-tied that way to be able to quickly deploy them 'cause that knot is so easy to undo. Yeah, YMMV.

That water knot is fine, but, when you're tired, in a cramped position, trying to tie the knot, feed the other end through and around, tension it.... So much easier to match the ends, whip in an overhand, tension, good to go. Simple, easy to inspect.

Wasn't there a fairly good train wreck (accident) not too long ago where folks blew the water knot in the anchor webbing and it pulled loose? Seem to recall.

Yeah, I wouldn't carry a knotted sling for climbing/canyoning use as an anchor sling with an EDK in it (ok, I have, but not normally), but...if I was cutting a long sling into anchor material...I dunno.

Report results!

Thanks.

I guess I'd feel better if it was backed up, which they usually aren't.

Yes, certainly there is a big benefit to simplicity and ease of tying.

Do you have a reference to that accident, Brian? Would be of interest. Taco?

Tom

Brian in SLC
04-18-2012, 10:54 AM
Nah, my bet is its here. Canyon accident. Maybe Red Rocks? Can't recall.

Seem to think they had set up a rappel from a tree or some such, and, the anchor failed. Eventually attributed to a poor water knot, I seem to dimly recall.

Iceaxe
04-18-2012, 11:24 AM
You fellers got me to wondering about water knot failures.... and I found this interesting info...

53022

Brian in SLC
04-18-2012, 12:26 PM
Yep, more Moyer test data. Wish that guy was still doin' that stuff. Ugh.

moabmatt
04-19-2012, 03:31 PM
Nah, my bet is its here. Canyon accident. Maybe Red Rocks? Can't recall.

Seem to think they had set up a rappel from a tree or some such, and, the anchor failed. Eventually attributed to a poor water knot, I seem to dimly recall.

Some folks in Bighorn Canyon in Arches a year or so ago.

Iceaxe
04-19-2012, 04:42 PM
I believe this might have been the orgianal post:




Isn't a catastrophic anchor failure the thought that horrifies every canyoneer? I experienced it last weekend. Fortunately, no one was killed or even hurt, just freaked out. We were at the top of the 225 foot down climb/rappel at the top of Bighorn canyon in Moab. Our group included several newbies and one scaredycat (me). We decided to rope the whole thing. We had a 300 and 200 foot rope. The substantial cedar at the top of the canyon was already slung with what looked like a new piece of 5/8th inch webbing. The water knot had about 4 inches of tail and a brand new rapide.

John had down climbed and rapped most of the way down to verify the rope reached the bottom. We had set up a Joker to facilitate getting our group down more quickly and to provide for a contingency. John had climbed up and was rapping back to the bottom as I hooked in to the other rope. As I backed down the canyon about 10 feet there was an alarming "thwonk" sound and the joker hardware shot past me but stopped just as I was to became an unwilling meat anchor. Horror stunned the group as we realized what had happened. John's angry shouts from below immediately told us that he was alive and conscious. He verified that he was alright but had to do some quick foot work to stay vertical.

As we examined what had happened, the water knot had pulled through with no more than 125 lbs of force on it. If John or somebody else had worked his way down to the 11 foot free rap near the bottom when the anchor failed someone could have really been hurt.

Lessons learned: I will never be able to trust non-standard webbing again. Redundant is important. Just because a rap isn't life threatening doesn't give you a license to be lazy or inattentive about anchors. Just because it worked for those that went before you doesn't mean it will work for you.

Has anyone else experienced a knot holding problem in small dimension webbing?

Steve


For what it's worth.... properly tied water knots don't pull through...

:cool2:

SlickRock
05-05-2012, 05:10 AM
Tom writes "the EDK / offset overhand bend works in ROPE, but we do not know if it works on webbing. Rope and webbing have significantly different properties. Therefore, we reached the conclusion we can recommend it for rope, and recommend AGAINST it for webbing. We just don't know, and can make a case for it working itself open in the more-slippery webbing. We hope to get it on a testing machine sometime soon."

Agree... now I've also seen a double fisherman's used instead of a water knot. While it looks like a cluster *^&# in webbing, I have never been able to untie a double fisherman's after it's been weighted and in place for a good length of time. I have been able to untie some water knots, however.

Does any data evaluate or compare the strength of the double fisherman's in webbing?

jeremy1701
05-05-2012, 06:14 PM
This is a great thread. Thanks for the info and the data.

ratagonia
05-06-2012, 02:52 PM
Tom writes "the EDK / offset overhand bend works in ROPE, but we do not know if it works on webbing. Rope and webbing have significantly different properties. Therefore, we reached the conclusion we can recommend it for rope, and recommend AGAINST it for webbing. We just don't know, and can make a case for it working itself open in the more-slippery webbing. We hope to get it on a testing machine sometime soon."

Agree... now I've also seen a double fisherman's used instead of a water knot. While it looks like a cluster *^&# in webbing, I have never been able to untie a double fisherman's after it's been weighted and in place for a good length of time. I have been able to untie some water knots, however.

Does any data evaluate or compare the strength of the double fisherman's in webbing?

Double Fisherman's works by a different mechanism, therefore, I consider it 100% in webbing. But would not choose it because:
A. excessively complex;
B. hard to inspect; and
C. impossible to untie.

Tom :moses:

Summit2Sea
05-08-2012, 02:52 PM
I guess since I'm killing time today and shooting out replies... :naughty: I'll throw my 2-cents in... Definitely like and prefer the water knot in webbing, although, I think as long as you're not cross-loading and have the proper tail length with a overhand/retraced knot it should be fine... I've rapped off natural anchors with over-hand knots in the webbing and as long as the knot looked good, was at the back and the diameter of say, the tree, wasn't such that it was causing it to cross-load or pull on itself I always thought it was fine... Theoretically I don't think it's much different than if you're rigging a frost knot or tying an overhand on a bight to create a loop and shelf... if you cut the loop you have a overhand knot...

ratagonia
05-08-2012, 03:14 PM
I guess since I'm killing time today and shooting out replies... :naughty: I'll throw my 2-cents in... Definitely like and prefer the water knot in webbing, although, I think as long as you're not cross-loading and have the proper tail length with a over-hand/retraced knot it should be fine... I've rapped off natural anchors with over-hand knots in the webbing and as long as the knot looked good, was at the back and the diameter of say, the tree, wasn't such that it was causing it to cross-load or pull on itself I always thought it was fine... I don't think it's much different than if you're rigging a frost knot...

Uh....

A retraced overhand knot IS a water knot, aka ring bend, technically an overhand bend.

An EDK is an offset overhand bend, ie, a cross-loaded overhand bend.

The title of this thread is confusing, because the question is not Water Knot vs. Overhand Knot, but I think the thrust was Water Knot vs. Offset Overhand Bend.

Not sure why BDC would call an EDK an "in-line overhand" - to me that means a Water Knot, not a cross-loaded overhand. If anything, it would be an off-line overhand. "Flat overhand" is again very non-specific.

With that, S2S, can you restate what you mean? Let's use the terms 'Water Knot' and 'EDK'.

Tom

Summit2Sea
05-08-2012, 03:57 PM
Uh....

An EDK is an offset overhand bend, ie, a cross-loaded overhand bend.

The title of this thread is confusing, because the question is not Water Knot vs. Overhand Knot, but I think the thrust was Water Knot vs. Offset Overhand Bend.

With that, S2S, can you restate what you mean? Let's use the terms 'Water Knot' and 'EDK'.

Tom

Ahhh, my bad... I was referencing the difference in using the water and overhand knots... :facepalm1:Yeah, not too much into using what we're calling the EDK aka offset overhand bend in the anchor webbing... I guess I would be concerned about it loosening up and possibly capsizing... Don't necessarily like cross loading knots or bends, although, don't mind using the EDK for pulling rope and if backed up would rappel off it...

Ken

ratagonia
05-08-2012, 04:01 PM
I was referencing the difference in using the water and overhand knots...

The term "overhand knot" either refers to

1. the simplest possible knot; or
2. any knot based upon the simple overhand knot.

So, a water knot IS an overhand knot, perhaps an overhand-family knot. Thus, I have no understanding of what the term "water knot vs. overhand knot" means ??? :ne_nau: :naughty: :crazy: :facepalm1: :slobber:

T

Summit2Sea
05-08-2012, 04:10 PM
The term "overhand knot" either refers to

1. the simplest possible knot; or
2. any knot based upon the simple overhand knot.

So, a water knot IS an overhand knot, perhaps an overhand-family knot. Thus, I have no understanding of what the term "water knot vs. overhand knot" means ??? :ne_nau: :naughty: :crazy: :facepalm1: :slobber:

T

Ok, I'm going to give up on this one... Lol... We'll just say the difference between the "water knot" & the "retraced overhand knot"... Did you really not know what I meant, Tom??? :0) I guess the flavor of this group is to be very accurate on terminology... ;0)

ratagonia
05-08-2012, 06:03 PM
Ok, I'm going to give up on this one... Lol... We'll just say the difference between the "water knot" & the "retraced overhand knot"... Did you really not know what I meant, Tom??? :0) I guess the flavor of this group is to be very accurate on terminology... ;0)

We're talking knots, and there IS a nomenclature. Words have specific meanings. When you use words that mean other things, yet the context implies something else... it makes my head hurt.

When I tie a water knot, I tie an overhand in one strand, and trace it back with the other end. That means it is a "retraced overhand knot", though more properly described as a "retraced overhand bend". Without "offset" in the name, it would be assumed to be loaded in-line, ie, like a water knot.

When I tie an EDK in rope, I put both strands together, and tie an overhand knot with both strands. Thus, it is not a retraced overhand knot.

:deadhorse: - I know, I know. It's dead, Jim. :facepalm1:

Perhaps a picture will help...

Tom :moses:

ilipichicuma
05-08-2012, 06:33 PM
We're talking knots, and there IS a nomenclature. Words have specific meanings. When you use words that mean other things, yet the context implies something else... it makes my head hurt.

When I tie a water knot, I tie an overhand in one strand, and trace it back with the other end. That means it is a "retraced overhand knot", though more properly described as a "retraced overhand bend". Without "offset" in the name, it would be assumed to be loaded in-line, ie, like a water knot.

When I tie an EDK in rope, I put both strands together, and tie an overhand knot with both strands. Thus, it is not a retraced overhand knot.

:deadhorse: - I know, I know. It's dead, Jim. :facepalm1:

Perhaps a pictures will help...

Tom :moses:

Those look the same.... :haha:

ratagonia
05-08-2012, 06:47 PM
Those look the same.... :haha:

C'mon Cliff, I expect better from you.

Flipped Left/Right and the Hue changed by 1/3...

T

Summit2Sea
05-08-2012, 08:24 PM
We're talking knots, and there IS a nomenclature. Words have specific meanings. When you use words that mean other things, yet the context implies something else... it makes my head hurt.

When I tie a water knot, I tie an overhand in one strand, and trace it back with the other end. That means it is a "retraced overhand knot", though more properly described as a "retraced overhand bend". Without "offset" in the name, it would be assumed to be loaded in-line, ie, like a water knot.

When I tie an EDK in rope, I put both strands together, and tie an overhand knot with both strands. Thus, it is not a retraced overhand knot.

:deadhorse: - I know, I know. It's dead, Jim. :facepalm1:

Perhaps a picture will help...

Tom :moses:

Oy vey... My head hurts now!!! :facepalm1:

Brian in SLC
05-11-2012, 09:54 AM
Not sure why BDC would call an EDK an "in-line overhand" - to me that means a Water Knot, not a cross-loaded overhand. If anything, it would be an off-line overhand. "Flat overhand" is again very non-specific.

Flat, abnormal, offset...yeah.

I've called the EDK "in-line" because that's how you tie it. Take two ropes, have them both run "in-line" to each other, and, toss into an overhand. Formed "in-line".

Could also argue that when you load it, the ropes are "in-line" and the knot doesn't hang up on an edge. Load path for the individual strands aren't.

Not sure where I heard it called an "in line" overhand...maybe Aussies? Can't recall.

Yeah, its cornfusing. EDK is easy.