Equalette Not Redundant

Eric Moss wrote:The problem to be solved: given two arbitrary protection points, what is the safest anchor to construct using those points?

Define what you mean by "safest".

Edit: damn it - missed csproul's post, but the question stands.

Jim Titt wrote:One worst case (the easiest to understand) is a belayer directly on the equalette and belaying a leader off the harness. If the leader falls before they get an intermediate piece or if that piece fails and the belayer catches them the force from the faller on the belayer is usually around 3kN-4kN (depends on the belay device). The total load is now maybe 4kN depending on the climbers weight so you are going to take a 6" fall directly onto a knotted sling with 407kg.

Jim, can you please clarify this comment? Specifically the part in bold. Where does the 407 kg come from? You seem to be interchanging force (kN) and mass (kg) and I am not sure I understand.

I think that it's important to point out that you cannot add the mass of the climbers together as thought that load is falling 6" statically onto the anchor. The belayer, if he is tied in directly, is; the climber, however, is connected (very) dynamically, so is a different loading scenario.

Brian L. wrote:It's interesting to look back on the rc.com discussions, and see the same people still passionately speaking out against these systems...10 years later.

Well, I've changed a number of opinions in the past ten years and "sharpened" others in the light of things I didn't originally know. But as a professor who has had to teach elementary things like calculus and linear algebra to generations of students, there is much to be said for preserving a passion for truth and understanding, even (or perhaps especially) when the subject is the same.

It does seem a bit sad that we pretty much understood most of this ten or more years ago and are still up against many of the same fallacies and misconceptions. Germany has the DAV, but we have nothing with anything close to the resources of that behemoth, and so the knowledge can lie fallow in the recesses of the internet and various engineering journals, only to be "reissued" for the latest round of questioners who are unaware of all that has gone before.

Brian L. wrote:It's interesting to look back on the rc.com discussions, and see the same people still passionately speaking out against these systems...10 years later.

Brian, I hope that partially explains my reaction in your "sliding X" thread. All this stuff has been rehashed over and over by people with LOTS of climbing experience: RGold, Jim Titt, Healyje, Patto, Marc801 and many others. But few people bother to make much effort to search.

If you're still open, check out this compilation from a year ago.
reddit.com/r/tradclimbing/c…

Nonworries wivanoff.

For the record I have done lots of research on this topic, even perused and seen the threads on rc, but the particular question I asked I never saw discussed.

Obviously the topic of this type of anchor just gets constantly derailed by the naysayers.

Fwiw, I make my own informed decisions, using my engineering background to try to understand all the factors. "Some guy on the internet" isn't a credible source. And thats what everyone on an internet forum is, regardless on their actual credentials, until they make their credentials known.

Not to dis Jim, as he has gained a lot of my respect, but look at his first response in my thread. Why would I pay attention to that?

I also tend to play devils advocate too...

Brian L. wrote:Fwiw, I make my own informed decisions, using my engineering background to try to understand all the factors. "Some guy on the internet" isn't a credible source. And thats what everyone on an internet forum is, regardless on their actual credentials, until they make their credentials known.

That is a poor approach to analyzing and filtering the good from the bad. Credentials alone mean very little. And to call to authority is a poor form of argument. Better to make a clear and logical argument based on known science.

Rgold is a professor in mathermatics but you wont find him dropping his credentials try to make his point.

JimTitt as far as I am aware does plenty of testing for a living. I believe he has tested prototypes for major climbing companies. He also manufactures and sells climbing bolts.

Yeah, my point is I don't take peoples words at face value. I do that analysis. And if I see a potential flaw in their logic I start asking questions.

But I pretty much ignore comments like, "no, don't do that, do this instead" with no backup explanation. It's not conducive to the discussion, and honestly I probably already know about what they are suggesting.

For me it still gets back to the fact that anchor failures aren't a prevalent source of climber injuries and deaths so I figure it's only worth so much energy and concern relative to the myriad things that will maim and kill you. But, hey, gotta pass the time on the internet somehow I suppose.

Brian L. wrote:However, what Long's testing does show is there are cases where extension isn't the factor everyone seems to make it out to be.

Are you referring to John Long's anchor book, which said that extension really isn't that big of a concern?

I'd like to hear rgold's take on that testing ;-)

Kent Richards wrote: Are you referring to John Long's anchor book, which said that extension really isn't that big of a concern? I'd like to hear rgold's take on that testing ;-)

It is on the previous page. You'll also find similar commentary from him at least as far back as 2006.

I know the "core group" is getting tired of rehashing and educating newer or unaware climbers about the issues in this forum.

Why not publish your own book on anchors? Then there would be a new book to displace the John Long book. You could go to Sterling (or Black Diamond ,etc) and get them to conduct tests on the issues you think are most important and designed the way you think is appropriate. Fixed Pin publishing here in Colorado is focused on publishing climbing related content and have published many books. They are soliciting ideas and authors for new books - seems like a good opportunity.

You could publish your credentials so you would be more than "just a guy on the internet". An appendix with how to locate the testing that other people have mentioned here would be valuable.

Maybe you would make some money...

What's worth noting regarding this conversation compared to Gri Gri debates, no accident prompted it, no injuries took place, no catastrophe occurred. Gri Gri flare up take place right after someone gets dropped and injured. User error? Flawed device? Bla bla bla. Does anyone have an actual equalette failure that led to an injury? I have never come across one. There was an unfortunate accident that led to the death of both climbers using a cordalette in Taquitz several years ago. The leader fell onto the anchor and witnesses heard three distinct pops in sequence. Cams pop when they blow. Total anchor failure. 400 feet to their death. Would have some equalization or better load distribution saved their lives? Nobody can say. But they violated sacred anchor rule number 2, Never fall directly onto your anchor, never factor 2!! They may have violated sacred anchor rule number 1 too, start with solids primary pieces.

What's nice about the equalette, when you hang on it, you will distribute your weight, your mass, your kilograms and your kilo Newtons on to at least two pieces. And when your partner clips in, you both will distribute your weight nicely on two pieces. This may make it easier to clean.

Equalettes may not have performed quite as well as originally suspected. But, they are just fine. If you don't like them, don't use them. And shut up. You are not saving lives. Like Healyj said there are far more important things to concern yourself with.

If you use an equalette, cordalette, boobolette, or vaj o'lette, you will be just fine as long as you remember sacred rule 1 and 2.

Kyle Tarry wrote: Jim, can you please clarify this comment? Specifically the part in bold. Where does the 407 kg come from? You seem to be interchanging force (kN) and mass (kg) and I am not sure I understand. I think that it's important to point out that you cannot add the mass of the climbers together as thought that load is falling 6" statically onto the anchor. The belayer, if he is tied in directly, is; the climber, however, is connected (very) dynamically, so is a different loading scenario.

I interchanged because I´m used to working in both! If you have a 98kg climber hanging at the belay (1kN) and he also stopping the falling climber with a braking force of 3kN then the total downward force on the climbers attatchment point to the belay is 4kN. This is 407kgf to make it easier to visualise that the load on the anchor is 4 times the belayers weight. Which is why we use different weights than the standard 80kg to test the effects of extension in belays.
You don´t add the mass of the two climbers together, you take the belayers mass and work out how fast it is being accelerated downward. He doesn´t fall with 1g, he has an additional 3g from the rope and faller.

Greg - John Long would say that his publishing of the book (and commencement of this debate) WAS in response to accidents, as he does a fair bit of accident analysis. He even brings up the same anchor failure case in Tahquitz, although he admits that catastrophic anchor failures are incredibly rare. Although you definitely should never fall on the anchor, that anchor was clearly not good enough - otherwise, it would have held a FF2 fall. Pieces blow, feet slip...this is why we strive to build rock solid anchors that can handle a worst case scenario, even if it's not always possible.

patto wrote: It is on the previous page. You'll also find similar commentary from him at least as far back as 2006.

Didn't see it on the previous page, but -- yeah -- I've been following rgold's comments on the matter for a while. Including the comments where he states that he was involved in the analysis of Long's test results for the book.

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from rgold on another thread :

Mal wrote: (2) In a climbing system the amount of additional shock load delivered from a blown anchor leg extending was so low that they were unable to measure it.

I keep posting cautions about this conclusion without much effect, perhaps because I'm inclined both personally and professionally to be circumspect in my phrasing. So let me violate those principles with a bold statement:

The way in which the test was performed reveals nothing about the anchor loads that would be experienced in practice during extension. (I am very sorry to say that John showed me a prepublication version of his text and asked for comments, and I failed to read the details of the test in question and so did not raise this important objection when I should have.)

The reason is that the extension in the tests was a small fraction of the amount of rope involved, and so even on theoretical grounds there would be no reason to expect much of a load increase. But in real life the fall energy produced by extension will have to be absorbed by the belayer's tie-in, which could be quite short, making the extension significant relative to the amount of rope available for energy absorbtion. This could result in high anchor loads and must be properly tested before one can say with even a small level of certainty that extension doesn't matter. (I might add, althougth this is part of another discussion, that the anchor load could easily become critical if the belayer attaches to an extending system with a sling or daisy rather than the climbing rope.)

Kent Richards wrote: Are you referring to John Long's anchor book, which said that extension really isn't that big of a concern? I'd like to hear rgold's take on that testing ;-)

This is from page 9 of the 37 page thread that was on rc.com in 2006
rockclimbing.com/cgi-bin/fo…

BTW, John Long went by vivalargo and by page 2 you can see patto raising concerns about extension when a belayer is in the mix.

Arlo F Niederer wrote:I know the "core group" is getting tired of rehashing and educating newer or unaware climbers about the issues in this forum. Why not publish your own book on anchors? Then there would be a new book to displace the John Long book. You could go to Sterling (or Black Diamond ,etc) and get them to conduct tests on the issues you think are most important and designed the way you think is appropriate. Fixed Pin publishing here in Colorado is focused on publishing climbing related content and have published many books. They are soliciting ideas and authors for new books - seems like a good opportunity. You could publish your credentials so you would be more than "just a guy on the internet". An appendix with how to locate the testing that other people have mentioned here would be valuable. Maybe you would make some money...

Though I can't find the post now, I have a vague memory of Long (aka, "Largo") posting on supertopo that he's compiling a new book on anchors.

My vague memory of the post also includes him saying something like he wants to correct some misinformation from the previous book, but I could be confusing that with something else.

As far as cred, could rgold perhaps be the Dr. Richard Goldstone who is mentioned in Long's latest book? Results in Google Books

Brian L. wrote:However, what Long's testing does show is there are cases where extension isn't the factor everyone seems to make it out to be.

Regarding the content of the book, even the authors contradict themselves on that matter:

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pp 137-138 (emphasis mine)

Basically Connally explains that true shock loading cannot occur. Mirroring recent testing done by Duane Raleigh at Rock & Ice magazine, he provides the example of a climber who clips to an anchor with a Spectra daisy chain, climbs a few feet past the anchor, then falls. The Spectra daisy means there's no energy-absorbing rope in the system, Connally says, and "forces rise incalculably high. In real-life situations where this has happened, hardware has broken and climbers have fallen to their deaths." That's true shock loading. But in the case of moderate extension found in the failed arm of a sliding X anchor, the aforementioned shock loading does not occur if there's dynamic rope in the system. An example would be to picture a climber hanging on 10 feet of rope. A placement blows and drops him a foot. Disaster? Unlikely, since that amounts to a fall factor 0.1, which is less than the averate of around 0.3 for most climbing falls. Granted, you avoid building anchors that could result in really long extension, but there's little cause to fear ordinary setups.

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The contradiction is in saying that true shock loading cannot occur, oh but wait, it actually can occur (and has killed people) in cases such as high FF drop onto an anchor with a relatively small "dynamic" element -- and, by the way, you don't want to build an anchor that results in "long" extension

I'd interpret "long" to mean extension that is long in the context of the whole system and the potential fall factor.

Appears to me that this is the exact situation that patto, rgold, and others are talking about, which the tests for the book did not include.

Edit: Heh, I changed the note about Richard Goldstone in the book so it sounded less snarky, but was too slow to avoid the quote below.

Kent Richards wrote: As far as cred, could rgold perhaps be the Dr. Richard Goldstone who is mentioned several times in Long's latest book?

Yes, one and the same.

Kent Richards wrote:The contradiction is in saying that true shock loading cannot occur, oh but wait, it actually can occur (and has killed people) in cases such as high FF drop onto an anchor with a relatively small "dynamic" element...

I don't believe this is correct and a rope and human in the equation is not a "small dynamic element" but a rather large one. I've held several FF2 falls and I don't believe one side of an equalette blowing wouldn't have made a significant difference in any of those cases other than adding to the beating. In all three cases the anchor was bomb and I would further suspect anyone having died from an anchor failure died on an anchor which was compromised from the beginning.

From where I sit the message isn't about equalette extension, it's about not using / building shit anchors.

wivanoff wrote:BTW, John Long went by vivalargo and by page 2 you can see patto raising concerns about extension when a belayer is in the mix.

Thanks for bringing that up. ;-)

Healyje wrote:From where I sit the message isn't about equalette extension, it's about not using / building shit anchors.

I completely agree.

My argument is less about the equalette and more about the continued spreading of false information that "shockloading" during an anchor extension doesn't occur. This is incorrect and perpetuating incorrect assertions doesn't help anybody.

So yeah. I believe that building anchors that have extension is not ideal. But I'm hardly worried about it. If a random partner I met in Camp4 belayed me off one I wouldn't care.