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3pt equalized anchor with limited extension

eli poss · · Durango, CO · Joined May 2014 · Points: 525

Yeah i wish. but that costs lots of money that i don't have. and if you know of a place that never has any precipitation or other weather to keep wimps like me from climbing, i am all ears.

rgold · · Poughkeepsie, NY · Joined Feb 2008 · Points: 526

Eli, that sling at the bottom, the one with three arms, a big knot, and the power point? That is a fixed-arm sling. The entire rest of the rigging can, at absolute theoretical best, do no better than to reproduce at the top anchor points the loads in the three arms of that bottom sling. So you have something elaborate and gear-intensive that cannot---even theoretically much less practically---perform any better than that bottom sling attached directly to the anchor points in classical cordelette fashion.

Edit: Sorry, this is wrong. If the three loads in the fixed arms are a, b, and c and if everything works perfectly without friction, then the three anchor loads would be (a+b)/2, (a+c)/2, and (b+c)/2. These will, in general, be more nearly equal than a, b, and c, so although the rig cannot equalize it could, in theory, reduce the degree of inequality. But that's in theory, the faraway place without friction where sliding systems go to actually work.

Somewhere on rc.com are about a thousand posts on "three point equalized anchors with limited extension." The whole thing (which I participated in) ended up looking like the labors of the alchemists trying to turn base metals into noble metals. Which is not to heap scorn on the attempts of either the alchemists or the rigging nerds gone wild. We should not forget that one of the great geniuses of all time, Isaac Newton, put considerable efforts into alchemy, a pursuit the probably led to his mental demise by way of mercury poisoning. Equalized rigging seems to be a less harmful, but no less quixotic pursuit.

Ray Pinpillage · · West Egg · Joined Jul 2010 · Points: 180
rgold wrote:Equalized rigging seems to be a less harmful, but no less quixotic pursuit.
Unless poor Eli hangs himself with the webbing to which he will have come full circle.
Trad Princess · · Not That Into Climbing · Joined Jan 2012 · Points: 1,175

My God

tenpins · · Unknown Hometown · Joined Jan 2007 · Points: 30

dude lemme tell you like this if TWO of your pieces ever came out, I wouldnt even answer your text messages. ever.

your concept is built on pieces failing. does it make sense that good placements are more important and valuable than all this nonsense?

if Im climbing with you, and Ive seen this - truly - Im wondering if you are geeking out about non extending equalized anchors that can communicate with the mothership, instead of the gear placements. By posting this you are communicating to me, a hypothetical partner, that you are actually OK with an _anchor placement_ failing.

eli poss · · Durango, CO · Joined May 2014 · Points: 525
tenpins wrote:dude lemme tell you like this if TWO of your pieces ever came out, I wouldnt even answer your text messages. ever. your concept is built on pieces failing. does it make sense that good placements are more important and valuable than all this nonsense? if Im climbing with you, and Ive seen this - truly - Im wondering if you are geeking out about non extending equalized anchors that can communicate with the mothership, instead of the gear placements. By posting this you are communicating to me, a hypothetical partner, that you are actually OK with an _anchor placement_ failing.
It is obvious that I'm just geeking out. i think you're reading into this a bit more than is true. that fact that this, to you, translates into "i have shitty placements and am fine with my pieces failing" says to me that you make too many assumptions. If i'm wrong about this, sorry for fasely assuming, if not, i'm glad i'll never have to see you. and besdides always a possibility to get 3 bombproof placements, and when it's not, one has to get creative.
Martin Harris · · Unknown Hometown · Joined Jan 2016 · Points: 200

Get your geek on but a sliding x binds way more than u realize when loaded reducing it's perfect equalization u get in your living room. I realize the AMGA does not know everything but there is a reason they teach a simple pre equalized anchor with a master point.

Mike · · Phoenix · Joined May 2006 · Points: 2,615

Just use the rope. It is the simplest, strongest, & most dynamic piece of gear you will be climbing with, and requires no extra doodads & widgets.

eli poss · · Durango, CO · Joined May 2014 · Points: 525
Mike wrote:Just use the rope. It is the simplest, strongest, & most dynamic piece of gear you will be climbing with, and requires no extra doodads & widgets.
Unless you have to escape the belay that is. and FWIW i've used the rope every time i've made an anchor in my limited multi-pitch experience.
rgold · · Poughkeepsie, NY · Joined Feb 2008 · Points: 526

It isn't any harder to escape from a rope tie-in if you've set it up right, and "setting it up right" is neither more complicated nor more time-consuming than installing a cordelette.

bearbreeder · · Unknown Hometown · Joined Mar 2009 · Points: 3,065

To "escape the belay" may not be much more conplicated with a rope anchor, but to free up the rope sure is

You basically need to rebuild the anchor with slings/cord .... Or cut the rope =P

Which is one of the reasons those playing "guide" use cord/slimg anchors ....

Transitioning into a counterbalance rap from a rope anchor is a biatch ... Many folks cant do it in a timely safe fashion even from a cord anchor, never mind a rope one

Keep in mind im a fan of rope anchors for swapping leads as well ... But a person using a rope anchor (not just in an emergency situation) needs to have a higher level of experience and skill for self rescue

;)

David Coley · · UK · Joined Oct 2013 · Points: 70
bearbreeder wrote:To "escape the belay" may not be much more conplicated with a rope anchor, but to free up the rope sure is You basically need to rebuild the anchor with slings/cord .... Or cut the rope =P
If you use a DIL belay then cut the rope works really well and is super quick.
Rob D · · Queens, NY · Joined May 2011 · Points: 30

In my head I picture this anchor being used by the guy that leads p1 and it's 60ft and 5.4, and then I get to the anchor and the next pitch is a rope-stretcher and my partner goes "well... I had all this extra gear, so I figured why not put it all in the anchor?"

Greg Maschi · · Phoenix ,Az · Joined Oct 2010 · Points: 0

Bet you have trouble finding partners, why not add a few more pieces of gear to this clusterf#ck?

eli poss · · Durango, CO · Joined May 2014 · Points: 525
Rob D. wrote:In my head I picture this anchor being used by the guy that leads p1 and it's 60ft and 5.4, and then I get to the anchor and the next pitch is a rope-stretcher and my partner goes "well... I had all this extra gear, so I figured why not put it all in the anchor?"
Well obviously I wouldn't do that if the next pitch was a route stretcher. And if I was swinging leads I can't imagine ever using this. I might do it if I was leading in blocks and there weren't any great gear placements available and I had to use 5 pieces. In that case better load distribution would be important. I'd use this for 3 pieces, an equalette for the other two and sitter equalette to connect all of them together. Or I build it with the rope and then rebuild it on my partner's side after I bring him/her up.
Jan Tarculas · · Riverside, Ca · Joined Mar 2010 · Points: 917
eli poss wrote: Well obviously I wouldn't do that if the next pitch was a route stretcher. And if I was swinging leads I can't imagine ever using this. I might do it if I was leading in blocks and there weren't any great gear placements available and I had to use 5 pieces. In that case better load distribution would be important. I'd use this for 3 pieces, an equalette for the other two and sitter equalette to connect all of them together. Or I build it with the rope and then rebuild it on my partner's side after I bring him/her up.
After looking at your profile and realizing you're only 18 and you stating you don't have "much multi-pitch experience", I would like to comment one thing...why don't you re-read all the responses by everyone here that are older and have much more multipitch experience. You would probably realize that you should just drop your idea and make it simple. I don't have that much experience as much as other posters here, but after climbing plenty of classics, I have never ran into a shitty belay where I needed 5 pieces of pro. Usually great routes have bolted belays or really good belay areas for pro.
eli poss · · Durango, CO · Joined May 2014 · Points: 525
Jan Tarculas wrote:I have never ran into a shitty belay where I needed 5 pieces of pro. Usually great routes have bolted belays or really good belay areas for pro.
just because you never have doesn't mean you never will. what if you were on a FA or on an adventure climb where you don't know what you will encounter. I have the common sense to know that, in most cases, simplicity and speed are more important and something this complicated will rarely if ever get used in the field. if you want to limit yourself to only climbing something you know has good gear and/or bolted anchors, that's fine, but knowing myself, i won't always be content with such. if you would like to provide some useful feedback, i would be more than happy to listen, but you are simply telling me something i already know.
Jan Tarculas · · Riverside, Ca · Joined Mar 2010 · Points: 917
eli poss wrote: if you would like to provide some useful feedback, i would be more than happy to listen, but you are simply telling me something i already know.
1. don't clip metal to metal (ie. the two biners you have on your first photo of your anchor set up

2. I might be wrong in this because of the angle of the photo, but your bottom 3 biners aren't actually clipped into the anchor into a sliding x configuration. It looks like they're just clipped to one strand of equallets you built.

3. mountainproject.com/v/equal…

4. This is direct from that link....Mathias pretty much described what your set up is.
Mathias wrote:

I had always wondered if a 3 piece equalized system could be achieve by doing this: Equalized and limited sling between point A and point B. Same setup with a separate sling from point B to point C. Then and a third equalized and limited sling from the central points of the first two slings to a master point in the middle. Overly complicated? Maybe, considering the limiters would need to be tied or adjusted for each anchor. But it would be an equalized 3 point anchor wouldn't it?

And the response from Jim Titt...
Are you talking about an equalised anchor (one that you used your skills to get the tensions in each leg the same) or a dynamically equalising anchor?
Either way it´s unlikely to produce equal loads on the pieces. The lowest sling splits the load 50/50 (if you are lucky/skilled) and the upper slings 50/50 again so 25% on each leg. The outer pieces are thus loaded 25% each and the middle one 50%. This simple principle is death to nearly all the multi-piece equalising systems promoted..."

5.
Jim Titt wrote:That the sliding X doesn´t equalise was shown back in 1984 if I remember correctly so nobody bothers to give any particular references. Once you accept that the friction over the karabiner will cause a load split of around 1.6:1 on the pieces (the karabiner factor of 1.6.1 for nylon rope over a karabiner was presented in a paper to the UIAA in 1964) then it follows that this will occur in a dynamic belay around each karabiner and the common setups display this perfectly. Various materials and wrap angles alter the actual values but the commonly used cords are generally higher than this around 1.7:1 and this is an unalterable physical effect despite claims by some to "perfectly equalise". I´ve tested all the common system for 3 point anchors, the sliding X with two karabiners, the Moosalette, ACR and the Alpine Equaliser. None achieve better load distribution than 15%/30%/55%. Unfortunately the sheer number of tests that have to be done on the various combinations of materials and systems and then the dynamic tests of the various failure modes mean the write-up I originally did is over 120 pages long, the condensed version is 36 sides and offers little more information than saying:- "Equalising systems don´t work very well and the penalty for a piece failing can be extremely high."
eli poss · · Durango, CO · Joined May 2014 · Points: 525

1 yes i know. i only did that to get a more equal length because i didn't have an extra 2' runner. i'm surprised nobody noticed that yet... or maybe everyone else was capable of ignoring that, as was intended.
2 yes that gets rid of the biner binding on the sling which limits the traditional sliding x from equalizing (that and friction)
3/4 no thats not the same thing. his set up would be, in theory, 25%-50%-25% because the middle piece has 2 legs and outer pieces have 1. in mine, all pieces have two legs and are, in theory, 33.3%-33.3%-33.3%
5 Yes i know i've read this before. Again, tell me something i don't already know

Will Cohen · · Denver, Co · Joined Dec 2012 · Points: 80
Jan Tarculas wrote: 1. don't clip metal to metal (ie. the two biners you have on your first photo of your anchor set up 2. I might be wrong in this because of the angle of the photo, but your bottom 3 biners aren't actually clipped into the anchor into a sliding x configuration. It looks like they're just clipped to one strand of equallets you built. 3. mountainproject.com/v/equal… 4. This is direct from that link....Mathias pretty much described what your set up is. Mathias wrote: I had always wondered if a 3 piece equalized system could be achieve by doing this: Equalized and limited sling between point A and point B. Same setup with a separate sling from point B to point C. Then and a third equalized and limited sling from the central points of the first two slings to a master point in the middle. Overly complicated? Maybe, considering the limiters would need to be tied or adjusted for each anchor. But it would be an equalized 3 point anchor wouldn't it? And the response from Jim Titt... Are you talking about an equalised anchor (one that you used your skills to get the tensions in each leg the same) or a dynamically equalising anchor? Either way it´s unlikely to produce equal loads on the pieces. The lowest sling splits the load 50/50 (if you are lucky/skilled) and the upper slings 50/50 again so 25% on each leg. The outer pieces are thus loaded 25% each and the middle one 50%. This simple principle is death to nearly all the multi-piece equalising systems promoted..." 5.
You lost your credibility at point 1.

Dave Macleod doing the forbidden practice

youtu.be/2yzvyAMIA3Q?t=3m
Guideline #1: Don't be a jerk.

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