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Three point anchor - The Saga Continues
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Jul 27, 2016
Rock Climbing Photo: Another three-point anchor with clove hitches.
Here is a three point anchor. What do you think?
Rock Climbing Photo: Three point anchor with clove hitches
Three point anchor with clove hitches


Edit: triaxial loading is a legitimate concern with this rig, more so with a d-shape biner. I think this biner is okay due to its symmetrical pear shape. Might be better and more convenient with a rap ring.

Here's why I prefer this to the tied cordelette: better equalization and a higher power point for a given v-angle.
Eric Moss
Joined Apr 15, 2016
98 points
Jul 27, 2016
Rock Climbing Photo: My most adventurous memory
Looks like the biner will be getting triaxal pull. Limiting the strength. This won't happen with a master point (just an overhand knot on a bite) or even the ever popular sliding X. Just want to the load the biner in its strongest axis regardless.


Rock Climbing Photo: Triaxal on the right
Triaxal on the right
Matt Kuehl
From Las Vegas
Joined Nov 29, 2010
1,444 points
Jul 27, 2016
Rock Climbing Photo: Another three-point anchor with clove hitches.
Thanks! That's certainly a good consideration. I'm not very worried about the triaxial loading because the cloves are basically touching under load, but I might use a rap ring instead of a biner.

This setup distributes load better than the cordelette, plus it has a higher anchor point for a given v-angle, so I prefer this one for now.

How do you make a three-point anchor with a sliding x? Equalette?
Eric Moss
Joined Apr 15, 2016
98 points
Jul 27, 2016
Rock Climbing Photo: Top of Rewritten, El Dorado
That's interesting! Seems similar to how I might approach this if building an anchor using just the rope. To avoid the tri-axial loading, you could perhaps also use two lockers, one for each clove. JRM89
From New Haven, CT
Joined Feb 17, 2015
348 points
Jul 27, 2016
Why are you using clove hitches for the master point 'biner? Is it for no extension? If so, it seems like the tried-and-true overhand or figure-8 on a bight master point would be the way to go. What advantage do the clove hitches add over a more traditional method?

Using a rap ring would solve the triaxial loading, but I think it's superfluous given that a standard cordelette setup is perfectly safe. Have you ever looked at the ACR setup? It uses a rap ring to facilitate "perfect" equalization. I've never actually seen somebody use it in practice though.

As for your cordelette being tied "rabbit runner" style (not in a loop), I love that and have been doing it for a couple of years now. I find it's much more versatile than the loop. Do keep in mind that any piece of your anchor with two strands running to it will take more of the load than the single stranded pieces. In practice this shouldn't matter much because most anchors are way stronger than necessary, but if you have marginal pieces in your anchor it could matter.
Ryan Strickland
From Idyllwild, CA
Joined Oct 30, 2010
175 points
Jul 27, 2016
Rock Climbing Photo: Another three-point anchor with clove hitches.
Good questions and thanks for the input!

I consider this to be an improvement over the ACR and the cordelette (tied master point).

I prefer it over the tied cordelette because it has a higher clip for a given v-angle and because it equalizes better.

I prefer it over ACR because it has no extension (the ACR does) and because it resists lateral forces and maintains equilibrium, whereas the ACR can be shifted out of equilibrium. It's also more redundant than the ACR because if the cord in the ACR is cut anywhere, the thing fails, whereas this gives a second chance with a cut anywhere if the clove hitches hold well enough.

I don't believe it's necessarily true that more strands means more force. It is true in this case, but if I moved the middle loop to either side, trading it for one of the ends, and re-equalized, then the middle piece would still get more force. I consider that the middle piece gets more force a necessity in a good three-point anchor, for now.
Eric Moss
Joined Apr 15, 2016
98 points
Jul 28, 2016
Eric Moss wrote:
What do you think?


Avoid.

guidetricksforclimbers.com/ind...

It is in general a good idea to use clove hitches on bolt-side binners (cordalette/webbing will slip a bit under shock-load, providing more dynamic load compensating), but clove hitches on the power-point is not the best idea.
Pavel Burov
Joined May 6, 2013
70 points
Jul 28, 2016
Rock Climbing Photo: Another three-point anchor with clove hitches.
Good article. Certainly counsels for the use of a rap ring over a biner. Like the article says, the clove is stronger than the bowline, so I don't see why to avoid it. Eric Moss
Joined Apr 15, 2016
98 points
Jul 28, 2016
Rock Climbing Photo: Ancient Art, of course.
Using a rap ring instead of a biner sounds clumsy. You'd have to keep the whole thing pre-tied (or feed the entire correlate multiple times to create the cloves at every belay) and figure out how to rack it neatly. gavinsmith
From Toronto, Ontario
Joined Feb 23, 2014
87 points
Jul 28, 2016
gavinsmith wrote:
Using a rap ring instead of a biner sounds clumsy. You'd have to keep the whole thing pre-tied


Alpine cock-ring, paulraphaelson.com/downloads/a...
Pavel Burov
Joined May 6, 2013
70 points
Jul 28, 2016
Rock Climbing Photo: Ancient Art, of course.
Pavel Burov wrote:


Interesting, think I'd seen that before and forgotten about it. Still seems more complicated once you add two cloves.
gavinsmith
From Toronto, Ontario
Joined Feb 23, 2014
87 points
Jul 28, 2016
Rock Climbing Photo: The crux of 6' man roof (5.11d).
If I'm using some cord to build the anchor instead of the rope, and especially if I'm leading in blocks, I prefer to have a convenient master point that the second can clip/tie into. This would seemingly require you both to tie into and untie from the same masterpoint biner.

"I prefer it over the tied cordelette because it has a higher clip for a given v-angle and because it equalizes better."

You can always clip your guide style belay device or have your second clip in above the shelf if that's a concern.
will ar
From San Antonio, TX
Joined Jan 11, 2010
231 points
Jul 28, 2016
I forget now where I saw it, maybe BD did it? But one of the carabiner manufacturers tested triaxial loading and found that there is a much smaller reduction in strength of the biner if the triaxial load is on the narrow side of the biner (so flip the biner around in the OP). But I also don't see why this would have any benefit over the overhand/figure 8 on a bight for the master point. With that it would be easier to clip multiple biners to the master point, where as with the cloves you can only have the one (or clip more biners to the one but then you are adding way to many directions of pull for me to be comfortable with it) Brady3
Joined Apr 18, 2014
16 points
Jul 28, 2016
Rock Climbing Photo: Another three-point anchor with clove hitches.
Brady3 wrote:
I forget now where I saw it, maybe BD did it? But one of the carabiner manufacturers tested triaxial loading and found that there is a much smaller reduction in strength of the biner if the triaxial load is on the narrow side of the biner (so flip the biner around in the OP). But I also don't see why this would have any benefit over the overhand/figure 8 on a bight for the master point. With that it would be easier to clip multiple biners to the master point, where as with the cloves you can only have the one (or clip more biners to the one but then you are adding way to many directions of pull for me to be comfortable with it)


So use a rap ring. I'll post a picture with the rap ring later. Thanks!
Eric Moss
Joined Apr 15, 2016
98 points
Jul 28, 2016
Rock Climbing Photo: Another three-point anchor with clove hitches.
will ar wrote:
If I'm using some cord to build the anchor instead of the rope, and especially if I'm leading in blocks, I prefer to have a convenient master point that the second can clip/tie into. This would seemingly require you both to tie into and untie from the same masterpoint biner. "I prefer it over the tied cordelette because it has a higher clip for a given v-angle and because it equalizes better." You can always clip your guide style belay device or have your second clip in above the shelf if that's a concern.


Thanks for the info. I have a few questions if you'll indulge me:

Why is the biner less convenient to clip to than a loop of cord?

Doesn't clipping above the shelf negate the redundancy of the tied cordelette?
Eric Moss
Joined Apr 15, 2016
98 points
Jul 28, 2016
looks very hard to untie if weighted heavily, cloves reduce breaking strength by about 50%? yeah looks like an anchor made with lead rope. tim naylor
Joined Mar 18, 2004
483 points
Jul 28, 2016
Rock Climbing Photo: Another three-point anchor with clove hitches.
tim naylor wrote:
looks very hard to untie if weighted heavily, cloves reduce breaking strength by about 50%? yeah looks like an anchor made with lead rope.


Thankfully, it's not very hard to untie. According to an earlier post, cloves reduce strength by at most 37%. Thanks for your help!
Eric Moss
Joined Apr 15, 2016
98 points
Jul 28, 2016
Eric Moss wrote:
So use a rap ring.


That would fix that issue, but I still don't see the benefit.
Brady3
Joined Apr 18, 2014
16 points
Jul 28, 2016
Rock Climbing Photo: Another three-point anchor with clove hitches.
Brady3 wrote:
That would fix that issue, but I still don't see the benefit.


Better equalization and a higher power point for a given v-angle.
Eric Moss
Joined Apr 15, 2016
98 points
Jul 28, 2016
Mountain Tools Webolette

Been using these for over 15 years. I carry two in the Big Wall length for multipitch trad. They are lightweight, easy to set up, and easy to manage. I don't work for Mountain Tools. It is just a great product and great shop.
TradRick
Joined Jun 27, 2016
31 points
Jul 28, 2016
Idk, seems clumsy and I had never enjoyed having a bunch of knots on a single biner, just become difficult to manipulate.

If you want to build with the rope, why not tried and true clove at the anchor points
JohnSol
Joined Sep 30, 2015
15 points
Jul 28, 2016
Rock Climbing Photo: Another three-point anchor with clove hitches.
JohnSol wrote:
Idk, seems clumsy and I had never enjoyed having a bunch of knots on a single biner, just become difficult to manipulate. If you want to build with the rope, why not tried and true clove at the anchor points


It's not for the purpose of building with the rope, it's a separate rig like the cordelette.
Eric Moss
Joined Apr 15, 2016
98 points
Jul 28, 2016
Rock Climbing Photo: Another three-point anchor with clove hitches.
J Marsella wrote:
I tried it for about 3 routes once before deciding it was not worth the unitasker gear. Now I go with either the rope (rabble rabble crusty trad guy) or a loop of cord (which could be used for bailing, tying off a tree, etc as needed). -- In general, this conversation is rehashed every few weeks, it seems, with a slight variation on the premise of "is this [particular version of an] anchor good/safe/acceptable/etc." In the end, it's going to be between you and your partner-- if s/he says "that anchor sucks, I hate it," you'll either quit using that method in favor of something that is acceptable to your partner, or you will find a new partner that accepts whatever non-standard (however safe, etc) anchor setup you choose.


What do you think about this setup? It is different from the ACR.
Eric Moss
Joined Apr 15, 2016
98 points
Jul 28, 2016
Rock Climbing Photo: Another three-point anchor with clove hitches.
Dear J,

Excellent! Thanks for the info. I can't quite picture what your three-piece rig is like. Is it an equalizing figure eight? Could you show me a picture of your three-piece rig?

It would be a pain to tie two cloves every time, but I plan to just leave them in and adjust them as necessary so I don't have to retie them.
Eric Moss
Joined Apr 15, 2016
98 points
Jul 28, 2016
I'm still sold on the "dynamically-equalizing & narrowly limited extension" approach to belay anchors, so this is more of an intellectual exercise for me but how about the following system for a statically-equalized 3-arm anchor? Are there reasons why this would not be suitable?

This set-up has a well-defined and easily clippable double-stranded central bight. Each arm is single-strand, providing more stretch and avoiding the "double-strand/double load on one pro" of your and other similar systems. And each arm can be easily adjusted independently of the others. It's essentially a variation on the DAV-recommended two-arm set-up, which is just one sling, with a bowline-on-a-bight (BoB) central point and a clove at each of the two pros. The third arm in this system is added by capturing the bight on an extra length of cord/rope when threading the BoB of the main loop. I tied a back-up knot below the pro clove of the 3rd-arm cord for added safety.

The system shown uses a short main loop and short extra arm to keep the image compact and the knots visible but in real life, these could be as long as they need to.

The independent clove adjustments mean that you can easily fine-tune the final position of the central point and angles of the arms after the set-up has been installed. Also, if you're concerned about most of the load going to the shortest arm (as it does in statically-"equalized" systems), you can loosen that arm to precisely the length you feel is necessary to compensate.

A well-known advantage of the BoB is that it remains easy to undo even after strong loading. Of course, for a 4-pro set-up, you would simply use two loops of cord/rope with the bight on one captured in the threading of the BoB on the other. Basically, you can just add the lengths and/or loops of cord/rope that you need for any number of arms (5, 6 or more!). The more you add, the more the knot above the central bight will grow (although not nearly as much as a typical cordelette-type knot in the same situation) but the the bight itself would remain an easy-to-clip two-stranded bight.

Capturing the extra bight(s) in the correct place when threading the BoB takes a tiny bit of practice but, once the trick has been learned, the whole set-up is very quick and straightforward.


Rock Climbing Photo: BoB 3+ arms
BoB 3+ arms
jktinst
Joined Apr 18, 2012
55 points
Jul 28, 2016
Rock Climbing Photo: Another three-point anchor with clove hitches.
Dear J,

Very nice. Thanks for sharing and for taking the time to draw that plan.
Eric Moss
Joined Apr 15, 2016
98 points


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