Three point anchor - The Saga Continues


Original Post
Eric Moss · Jul 27, 2016 · Unknown Hometown · Joined Apr 2016 · Points: 0
Here is a three point anchor. What do you think?
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.

Matt Kuehl · Jul 27, 2016 · Las Vegas · Joined Nov 2010 · Points: 1,300
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.

Triaxal on the right

Eric Moss · Jul 27, 2016 · Unknown Hometown · Joined Apr 2016 · Points: 0
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?

JRM89 · Jul 27, 2016 · New Haven, CT · Joined Feb 2015 · Points: 315
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.

Ryan Strickland · Jul 27, 2016 · Idyllwild, CA · Joined Oct 2010 · Points: 126
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.

Eric Moss · Jul 27, 2016 · Unknown Hometown · Joined Apr 2016 · Points: 0
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.

Pavel Burov · Jul 28, 2016 · Unknown Hometown · Joined May 2013 · Points: 25
Eric Moss wrote:What do you think?
Avoid.

http://www.guidetricksforclimbers.com/index.php/appendix/78-gtc-articles/78-use-and-abuse-of-the-clove-hitch

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.

Eric Moss · Jul 28, 2016 · Unknown Hometown · Joined Apr 2016 · Points: 0
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.

gavinsmith · Jul 28, 2016 · Toronto, Ontario · Joined Feb 2014 · Points: 23
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.

Pavel Burov · Jul 28, 2016 · Unknown Hometown · Joined May 2013 · Points: 25
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/download...

gavinsmith · Jul 28, 2016 · Toronto, Ontario · Joined Feb 2014 · Points: 23
Pavel Burov wrote: Alpine cock-ring, paulraphaelson.com/download...
Interesting, think I'd seen that before and forgotten about it. Still seems more complicated once you add two cloves.

will ar · Jul 28, 2016 · San Antonio, TX · Joined Jan 2010 · Points: 215
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.

Brady3 · Jul 28, 2016 · Unknown Hometown · Joined Apr 2014 · Points: 15
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)

Eric Moss · Jul 28, 2016 · Unknown Hometown · Joined Apr 2016 · Points: 0
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 · Jul 28, 2016 · Unknown Hometown · Joined Apr 2016 · Points: 0
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?

tim naylor · Jul 28, 2016 · Unknown Hometown · Joined Mar 2004 · Points: 370
looks very hard to untie if weighted heavily, cloves reduce breaking strength by about 50%? yeah looks like an anchor made with lead rope.

Eric Moss · Jul 28, 2016 · Unknown Hometown · Joined Apr 2016 · Points: 0
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!

Brady3 · Jul 28, 2016 · Unknown Hometown · Joined Apr 2014 · Points: 15
Eric Moss wrote: So use a rap ring.
That would fix that issue, but I still don't see the benefit.

Eric Moss · Jul 28, 2016 · Unknown Hometown · Joined Apr 2016 · Points: 0
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.

TradRick · Jul 28, 2016 · Unknown Hometown · Joined Jun 2016 · Points: 0
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.

JohnSol · Jul 28, 2016 · Unknown Hometown · Joined Sep 2015 · Points: 0
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

Guideline #1: Don't be a jerk.

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