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majid_sabet


Jul 21, 2012, 8:42 AM
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Re: [rgold] Building anchors with the rope [In reply to]
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I wonder how many pages of scientific papers you write every time you climb


Partner cracklover


Jul 23, 2012, 10:03 AM
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Re: [LostinMaine] Building anchors with the rope [In reply to]
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I ran into a guide teaching anchor-building in Eldo yesterday. Inspired in part by this thread, I asked him an open-ended question about what techniques he taught climbers to build anchors, to see what his response would be. He never brought up using the rope. When I asked him about using the rope, he said sure, if it was straightforward, he'd "clip in with the rope". I asked him - what about building the anchor with the rope? The answer was interesting.

Basically, what it boiled down to was that he felt that none of his clients could comprehend the situation well enough to build an anchor with the rope. He said that even in his multi-pitch clinic, in which it would most make sense to show rope-anchors as a useful tool, he did not do so unless specifically asked to (and I got the impression he'd never been asked to).

I suspect that he's not alone. My guess is that it's just too much trouble for many guides to fully cover, and give all the necessary context around, rope-only anchors. It's certainly easier for them, and quicker for the client, to show how to build an anchor with a cordelette.

One thing I wish I'd asked him was whether he himself, in his own recreational climbing, ever built a rope-only anchor.

GO


bearbreeder


Jul 23, 2012, 11:19 AM
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Re: [cracklover] Building anchors with the rope [In reply to]
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exactomundo .... and when they do show it, it is something extremely simple ... such as clove the outer pieces, pull through the rope in between the middle piece and fig 8 the bights ...


KISS ...

we can argue about all the fancy rope anchors we want, but the above will work as well for all practical purposes as any of the other proposed anchors here and is simple enough to remember when you are cold, tired, hungry, in the dark and out of slings on the 15th pitch of a climb even if youve only built it once or twice before ...

Wink


majid_sabet


Jul 23, 2012, 11:49 AM
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Re: [cracklover] Building anchors with the rope [In reply to]
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cracklover wrote:
I ran into a guide teaching anchor-building in Eldo yesterday. Inspired in part by this thread, I asked him an open-ended question about what techniques he taught climbers to build anchors, to see what his response would be. He never brought up using the rope. When I asked him about using the rope, he said sure, if it was straightforward, he'd "clip in with the rope". I asked him - what about building the anchor with the rope? The answer was interesting.

Basically, what it boiled down to was that he felt that none of his clients could comprehend the situation well enough to build an anchor with the rope. He said that even in his multi-pitch clinic, in which it would most make sense to show rope-anchors as a useful tool, he did not do so unless specifically asked to (and I got the impression he'd never been asked to).

I suspect that he's not alone. My guess is that it's just too much trouble for many guides to fully cover, and give all the necessary context around, rope-only anchors. It's certainly easier for them, and quicker for the client, to show how to build an anchor with a cordelette.

One thing I wish I'd asked him was whether he himself, in his own recreational climbing, ever built a rope-only anchor.

GO

what a waste of paying a guide or an instructors when they do not even cover the basic such as building an anchor with rope.


Partner cracklover


Jul 23, 2012, 1:05 PM
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Re: [bearbreeder] Building anchors with the rope [In reply to]
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bearbreeder wrote:
exactomundo .... and when they do show it, it is something extremely simple ... such as clove the outer pieces, pull through the rope in between the middle piece and fig 8 the bights ...


KISS ...

we can argue about all the fancy rope anchors we want, but the above will work as well for all practical purposes as any of the other proposed anchors here and is simple enough to remember when you are cold, tired, hungry, in the dark and out of slings on the 15th pitch of a climb even if youve only built it once or twice before ...

Wink

Well, it may or may not be simple, but... this is the second time you've described your anchor system, and thought I'm reasonably good at envisioning such things in my head, I still haven't the slightest idea what you're trying to convey.

GO


bearbreeder


Jul 23, 2012, 1:09 PM
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except with the climbing rope ... and cloves instead of barrel knots


Partner cracklover


Jul 23, 2012, 1:58 PM
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Re: [bearbreeder] Building anchors with the rope [In reply to]
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So correct me if I'm wrong - what you're trying to convey is as follows (for a three piece anchor):

1 - Clove hitch the outer two pieces with a whole shit-ton of slack between them.

2 - Clip the slack to the middle piece, pull the arms down (like you would with a cordelette) and tie a big Fig-8 knot with those two arms.

Couple issues: 1 - How do you know how much slack to leave when clove hitching the second piece? Seems like it would take a few tries to get it right. 2 - You're putting twice the force on the middle piece as on the two outer ones. Not a deal-breaker, but certainly worth noting, as most of the other anchor systems mentioned here do not do that.

GO


JimTitt


Jul 23, 2012, 2:28 PM
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Re: [cracklover] Building anchors with the rope [In reply to]
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[quote "cracklover" 2 - You're putting twice the force on the middle piece as on the two outer ones. Not a deal-breaker, but certainly worth noting, as most of the other anchor systems mentioned here do not do that.
I think youll find this is not the case, unless this is going to be a horribly complex discussion on the different stretch in the doubled strand compared with the single strands.


bearbreeder


Jul 23, 2012, 4:55 PM
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Re: [cracklover] Building anchors with the rope [In reply to]
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Jim answered part of yr question

As to slack, its pretty simple just place the pieces , clove one, pull through the bights till u havr enough for a fig 8 and then clove the other... Then tie the fig 8

Im not claimings its the fastest or the "best" ... What i am saying i that it is so simple and stupid that even i can remember it even when distracted by a hawt lulu clad partner ... As can anyone else who has ever built a cord anchor ... Which it basically is

My view is that while there are those who have their fancier systems and use em all the time, which there is nothing wrong with ... I prefer something absolutely simple that works an that ill never forget even when being pecked at by nesting falcons ... An if i show someone whos never done it before, KISS

Wink


Partner rgold


Jul 24, 2012, 8:57 AM
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Re: [JimTitt] Building anchors with the rope [In reply to]
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Jim, you certainly have a better sense about what happens in testing situations, but there is nothing particularly complex about Gabe's assertion.

Assume, for simplicity, that the three pieces are very close together so that all arms are of the same length and the contribution of the arm angles is negligible. When the power point is loaded, it displaces downward a certain amount, which means that all arms elongate by that single amount. Since the arms are the same length, their percentage stretch is the same for all four arms, which means the tension in all four is the same. Given that the middle two arms connect to the same single point, it gets twice the load of the outer pieces, as Gabe said.

In the past, this simplistic type of reasoning has proven to correspond very well to experimental results, and I'd guess the same will be true here. Of course the center piece load won't be exactly twice as much, but I'd predict a very significant difference, even when the arms are nearly the same length.

I also have to say that I am genuinely puzzled that making four clove hitches in an obvious sequence could be considered so complicated as to require a "simpler" version that brings back all the adjustment issues and uncertainties of the cordelette, adds the need to guess, for each new anchor configuration, the correct amount of slack to leave for forming the figure-8, uses 2/3 more rope, will, I believe, prove to have the loading issues Gabe mentioned (although I'm prepared to be wrong on that if Jim says so) and is perhaps worse than the cordelette because the belayer is tethered to just one piece rather than the power point.

I think the method I described is better than a cordelette for many anchoring situations. If you are just going to make a cordelette out of the rope and get something not quite as good, why bother? Stick with the cordelette---that would be the K.I.S.S. solution for those choices, at least in my opinion.

I guess the answer is that both simplicity and stupidity are in the eye of the beholder where K.I.S.S. is concerned, eh?


Partner cracklover


Jul 24, 2012, 9:22 AM
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Re: [bearbreeder] Building anchors with the rope [In reply to]
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bearbreeder wrote:
As to slack, its pretty simple just place the pieces , clove one, pull through the bights till u havr enough for a fig 8 and then clove the other... Then tie the fig 8

Ah, that makes much more sense. BTW, that's not what you said earlier. Thanks for the clarification.

Edited (because BB is still describing something different from what i think he actually does ) to add the following:

So you:
1 - Clove hitch the first outside piece
2 - Clip the middle piece and the second outside piece
3 - Pull down the two arms (between the middle and outside pieces) and make a big fig-8 knot with both bights together.
4 - Take the rope you clipped through the second outside piece and turn it into a clove on that biner.
5 - Use that big knot in the middle as your power-point, and clip yourself into it.

As for the forces - maybe I need to go all the way back to my HS physics textbooks, but I don't see why the middle piece, with double the connections to the power-point, wouldn't see double the force.

GO


(This post was edited by cracklover on Jul 25, 2012, 8:14 AM)


bearbreeder


Jul 24, 2012, 10:20 AM
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Re: [cracklover] Building anchors with the rope [In reply to]
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well let me ask you this ... even if it sees a bit more force ... does it really matter ... we all know the shortest length of an anchor will generally see more force than that of the longer arms ... true equalization aint really happening regardless IMO

you can simply make the piece with the doubled up arm the longest one ... or the strongest one ... etc ... rarely will you have an anchor where all the pieces are equally strong or of absolutely equal length ...

remember that you care constructing it with dynamic climbing rope ...

as to simplicity and cord anchors ... you can make the RC arguments over and over again till we get to 50+ pages ... but my view of showing people how to anchor with the rope is that theyll likely use it when they run out of slings or get to the top of a pitch and forgot the cord on their partner ... so they need something absolutely and utterly simple which they can remember even if theyve only done it once or twice ...

if they constantly build rope anchors all the time, then sure, they can likely remember how to build it over and over again ... but i can tell you that there is no way they will forget the way i pictured above if they use cord anchors

which for all practical purposes will work just as well as anything here ...

Wink


wivanoff


Jul 24, 2012, 10:42 AM
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Re: [rgold] Building anchors with the rope [In reply to]
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rgold wrote:
The only time I carry a cordelette is for big-wall climbing or on free climbs if I expect to do all the leading, and even then only if the climb has enough pitches to make time for belay changeovers important...

rgold:
Could I ask please, when you DO use a cordelette, do you tie it as a "standard" cordelette with the big central knot or do you tie something else - perhaps using clove hitches for adjustment? Thanks.


JimTitt


Jul 24, 2012, 10:49 AM
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rgold wrote:
Jim, you certainly have a better sense about what happens in testing situations, but there is nothing particularly complex about Gabe's assertion.

Assume, for simplicity, that the three pieces are very close together so that all arms are of the same length and the contribution of the arm angles is negligible. When the power point is loaded, it displaces downward a certain amount, which means that all arms elongate by that single amount. Since the arms are the same length, their percentage stretch is the same for all four arms, which means the tension in all four is the same. Given that the middle two arms connect to the same single point, it gets twice the load of the outer pieces, as Gabe said.

In the past, this simplistic type of reasoning has proven to correspond very well to experimental results, and I'd guess the same will be true here. Of course the center piece load won't be exactly twice as much, but I'd predict a very significant difference, even when the arms are nearly the same length.

I also have to say that I am genuinely puzzled that making four clove hitches in an obvious sequence could be considered so complicated as to require a "simpler" version that brings back all the adjustment issues and uncertainties of the cordelette, adds the need to guess, for each new anchor configuration, the correct amount of slack to leave for forming the figure-8, uses 2/3 more rope, will, I believe, prove to have the loading issues Gabe mentioned (although I'm prepared to be wrong on that if Jim says so) and is perhaps worse than the cordelette because the belayer is tethered to just one piece rather than the power point.

I think the method I described is better than a cordelette for many anchoring situations. If you are just going to make a cordelette out of the rope and get something not quite as good, why bother? Stick with the cordelette---that would be the K.I.S.S. solution for those choices, at least in my opinion.

I guess the answer is that both simplicity and stupidity are in the eye of the beholder where K.I.S.S. is concerned, eh?

Hey, it was a joke! Well, more or less since it offered another pathway to a thousand-post discussion on whether the lower rope stretch because of the double strand would be counteracted by increased slippage throught the knot (2 strands to slip not one), where do the cloves come in the picture and so on.
All on pieces where (as in most of these type of anchors) one is merely guessing the strength anyway.

Personally I like it and would use it if circumstances called for that type of centre point.


Partner rgold


Jul 24, 2012, 11:56 AM
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Re: [bearbreeder] Building anchors with the rope [In reply to]
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bearbreeder wrote:
well let me ask you this ... even if it sees a bit more force ... does it really matter ... we all know the shortest length of an anchor will generally see more force than that of the longer arms ... true equalization ain't really happening regardless IMO

Of course true equalization ain't happening---damn, I'm one of the people who spent years trying to explain that to the SRENE crowd. But if you properly understand anchoring strategy, then whether the extra load will "make a difference" is not the point to focus on, because we don't know whether and/or when it might, in fact, make a difference.

Perhaps it is just the mathematician orientation that I can't escape, but it seems to me that, faced with various methods of equal implementation complexity (which is what the several proposals here are) the most sensible approach is to choose the one with the best theoretical properties. Of course, things such as knot behavior will will introduce variation into the actual results, but starting with a situation that is theoretically optimal means that your real-life variation also starts from an optimal position.

On the other hand, starting with a position that, for instance, substantially overloads one of the anchors (well beyond the contribution of anchor length) means that your variation will be around that skewed position. Why choose a suboptimal starting point when we know better and it is no harder to chose an optimal alternative? That's what I don't get about the "what difference does it make really" argument.

bearbreeder wrote:
as to simplicity and cord anchors ... you can make the RC arguments over and over again till we get to 50+ pages ... but my view of showing people how to anchor with the rope is that they'll likely use it when they run out of slings or get to the top of a pitch and forgot the cord on their partner ... so they need something absolutely and utterly simple which they can remember even if they've only done it once or twice ...

This is a different question. Perhaps I should have read your response more carefully. If the issue is not the optimal way to do something, but rather a method that will be employed by people who will very rarely use it, then it makes sense to find a procedure that is as much possible like the method they've practiced.


notapplicable


Jul 24, 2012, 12:50 PM
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bearbreeder wrote:
My view is that while there are those who have their fancier systems and use em all the time, which there is nothing wrong with ... I prefer something absolutely simple that works an that ill never forget even when being pecked at by nesting falcons ... An if i show someone whos never done it before, KISS

I just started climbing with a longtime sport/gym climber who wants to get in to gear routes. I showed her how to build the anchor once then asked her to build her own and walked away to pack up some gear. When I came back she was hanging from a perfectly duplicated anchor while fine tuning the tension at the clove hitches.

Perhaps she's smarter than the average gym rat but I don't think she will have any trouble remembering it the next time out. No one else I've showed it to seemed to struggle with the concept either. Some have adopted it and some preferred their original method but no one has complained about it being too complicated.


bearbreeder


Jul 24, 2012, 5:53 PM
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Ive had climbers totally freak out on a wall once they get cold, tired and hungry ... Its one thing to be able to do it right after someone shows u on the ground, and another to be able to remeber as the sun is setting, as its startin to drizzle, above freezing, or when yr dehydrated, etc... Especially if the last time u did it was a yer or two ago

Until u have someone whos knows their knotsfumble to tie clove hitches and a basic gear anchor setup at the end of the day on a climb,you dont realize how much even the simplest tasks go wrong when someone is out of it

Like i said im not claiming in any way that the method pictures above is "optimal" or the "best" ...

What i AM saying is that it will work just fine for all pratical purposes, is something thats works well for the most common reason the average climber ties in with the rope, ie they dont have any more gear ... And is something youll remember how to do easily and not screw up in bad conditions even years after you last used it ...

KISS


notapplicable


Jul 24, 2012, 10:04 PM
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Teaching one less than ideal system to take up the slack (so to speak) for another less than ideal system seems kind of like a circle jerk. I would rather teach a new partner an ideal anchoring system that will last a lifetime and show them the less than ideal systems for rare occasions when the primary just doesn't work out.


bearbreeder


Jul 24, 2012, 10:21 PM
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you can argue about "ideal" all you want ... like i said for all practical purposes the anchor i pictured will work just fine, except on RC ;)

you are never going to have perfect equalization regardless, and if you are worried, just make the doubled arm the longest one, which might actually give you better real "equalization" considering that the shortest arm usually takes more than its share of the load anyways

or simply clip it into yr strongest piece ... rare are the anchors IME where all pieces are absolutely equally strong and of absolute equal length ...

2 opposed quickdraws arent theorectically ideal for TR anchors, but they work ... belaying off yr harness with no redirect aint idea either ... sliding Xs arent ideal in a rope anchor, yet someone listed it (and john long for bolt anchors) here, along with series anchor example with the rope by craig luebben in his anchor book ...

if climbing teaches you anything is that there aint no "ideal" or "best" or "optimal" ... just what works bet for the person and the situation ...

the climber i run away from at the crag is the one who tries to claim that his way is ideal and youre doing it wrong ... like RC

Tongue


(This post was edited by bearbreeder on Jul 24, 2012, 10:45 PM)


Partner rgold


Jul 29, 2012, 7:33 AM
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From:
Get Out on Rock---An Instructional Guide to Rock Climbing
Libby Peter and Neil Gresham

Here is my so-called Bazillion anchor, rigged for just two pieces and using the rope loop rather than creating a master point. To rig three pieces, the rope that is lying on the ledge is cloved to the third piece.



Excerpt from http://www.ukclimbing.com/...les/page.php?id=2592

Although it may seem like news here, it is obviously old-hat in the U.K., where, apparently, they dare to imagine that beginners can actually master the purported American-mind boggling complexity of this method.

Have cordelettes really made American beginners and intermediates too dumb to master this, as Gabe's conversation with a guide suggest?

(Of course not, but there is such a thing as the self-fulfilling prophecy...)


bearbreeder


Jul 29, 2012, 7:45 AM
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remember that the majority of climbers are weekend warriors at best these days ... that means that they are likely to do a real multipitch with gear anchors at most a few times a year ... and these days theyll tend to use a cord or sling for the anchors, which makes very good sense when you realize that a good proportion of these weekend warriors dont swap leads, but rather block lead, often because one of the leaders is more experienced or the better climber

so in short, theyll likely use rope anchors in more of an "emergency" situation, and very possibly in poor conditions ... they need something thats simple, safe, reliable and that theyll never forget how to do even when their hands are shaking ...

as to all the "unequalizing" effect of the anchor i posted .. notice that metollius recommends the same method with their equalizing sling in their instructions ... i think theyd know a thing or two Tongue




JimTitt


Jul 29, 2012, 8:39 AM
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The concerns are probably more that one anchor point will have half the stretch than the others and with rope this might have more effect than say with low-stretch tape or cord. (Id just put the double strand on the strongewst piece). But the cloves on the two singles will give a bit and the centre knot a big unknown as well anyway. Since its a nice way to get the master point though Ill test it this evening rather than watching some obscure sport.

Interesting that Metolious arent embarassed to call their sling an equaliser and illustrate it clearly doing nothing of the kind!


bearbreeder


Jul 29, 2012, 9:40 AM
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what i personally dont understand is the belief that rope climbing anchors will provide better load distribution than lower stretch cord or slings where the legs are uneven ... or than the method i listed

i suspect that with stretchy rope, the uneven forces will be even worse than the pic listed below from mr longs book ...

id be quite interested in the test ... not that it will change anything here one way or another Tongue




(This post was edited by bearbreeder on Jul 29, 2012, 9:45 AM)


Partner rgold


Jul 29, 2012, 10:22 AM
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The picture in Long's book gives the hypothetical load distribution obtained by assuming the sling material obeys Hooke's Law. Tests subsequently showed that the estimates given by basic theory were on target.

Even materials that don't obey Hooke's Law in general have it as their first-order approximation, which means that they "nearly" obey it for small displacements. This is the basis for engineering calculations on deformation of steel beams, for example, which are not exactly what you'd call "stretchy."

The tricky part comes in understanding, for a given material, what constitutes a "small displacement." Whether climbing load displacements are "small" for the webbing in the Metolius Equalizer is something I don't know, but the point is that we don't have to postulate some high level of "stretchiness" to see the kinds of load inequalities predicted by Hooke's Law.

If the Hooke's Law approximation is appropriate, which I suspect it is without knowing for sure, then the Metolius "Equalizer," rigged as in their illustration, will have the same substantial loading inequality Gabe mentioned for rope configurations, in which case an equalizer it ain't.

Edit: Hooke's Law says that the tension in a loaded material is proportional to its percentage deformation.


(This post was edited by rgold on Jul 29, 2012, 10:27 AM)


bearbreeder


Jul 29, 2012, 10:35 AM
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there is an easy solution ... ill simply ask metollius if there is "double" the force on the middle piece as on the others in their recommended setup

my point is simply that quite a few of these rope tie in systems listed in this thread dont IMO provide "ideal" load sharing, especially in uneven arm lengths ...

also with the method i listed above, at least i can choose which piece will receive more of the load, either the farthest which typically sees a much lower load, or the strongest which will take it the best ...

its also quite simple to remember Wink

again im not claiming its the best or "ideal" like others ...

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Forums : Climbing Disciplines : Trad Climbing

 


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