Direct belay off of series anchor variations

curt86iroc wrote:

i don't understand this setup at all. what is the sling doing? as far as i can tell, the sling has 0 load on it when your climber falls...

Looks to be backing up the bolt. 

Malcolm Daly wrote: Sorry I wasn’t too clear. The direct belay is really only suitable for bolted belays or absolutely bomber multidirectional anchors. 

Fixed point aka direct belays commonly employ bolts and ice screws for ease, but they aren't requires. They are also readily constructed from gear anchors. Make a masterpoint and then tie it down to an upward pull piece using the backside of the belayer's clove hitch. If I remember (and translated) correctly, the German term for this is "power triangle." 

Jeremy Cote wrote:

Looks to be backing up the bolt. 

but i don't see how this makes sense. In order for that sling to load, the bolt would need to fail...and at that point, that dynemma and pin are gonna be shock loaded...

Unless i'm missing something obvious, this is basically a single point anchor on 1 bolt with a loose sling not holding any load... the sling and pin are incorporated for looks only, they aren't actually adding any value in the anchor.

curt86iroc wrote:

but i don't see how this makes sense. In order for that sling to load, the bolt would need to fail...and at that point, that dynemma and pin are gonna be shock loaded...

Unless i'm missing something obvious, this is basically a single point anchor on 1 bolt with a loose sling not holding any load... the sling and pin are incorporated for looks only, they aren't actually adding any value in the anchor.

I'd say not for "looks only".  I suspect at least the belayer would be happy to have the sling attached to the second bolt should the first bolt fail. 

Bill Lawry wrote:

I'd say not for "looks only".  I suspect at least the belayer would be happy to have the sling attached to the second bolt should the first bolt fail. 

i guess my point is, if there is enough of a force to break that hanger or bolt, that pin and sling aint doing nothing... it's there just to make the belayer feel good...

Yes. Take to heart the above admonishments that the primary bolt/pin/whatever needs to be bomber. 

curt86iroc wrote:

but i don't see how this makes sense. In order for that sling to load, the bolt would need to fail...and at that point, that dynemma and pin are gonna be shock loaded...

Unless i'm missing something obvious, this is basically a single point anchor on 1 bolt with a loose sling not holding any load... the sling and pin are incorporated for looks only, they aren't actually adding any value in the anchor.

The photo you are questioning is really no different than the op photos. In all op photos one piece will take 100% of a lead fall load.  The other piece is merely a back up.  And, the potential extension would be even greater than the photo you are questioning.  The only difference, in a few of the op photos, the belayer is attached to the other piece. Body weight only here. Not a significant difference. 

A well placed pin in good condition can be extremely strong. 

Go easy on the term shock load. 

Meh, to each their own I suppose. Call me old fashioned, but I like some load sharing properties in my anchors...

curt86iroc wrote: Meh, to each their own I suppose. Call me old fashioned, but I like some load sharing properties in my anchors...

Honestly, first time I saw it online was a couple years ago. I had virtually the same reaction.

But later I found myself in a situation for which this would have probably been the best solution.
Have I actually used it? No. But next time in similar circumstances, I won’t hesitate.

A hybrid strategy---admittedly specialized---with ordinary gear anchors is to install a Munter on the anchor, pull up a bunch of slack---enough for the leader to reach good protection---and at the end of that slack install a belay gadget clipped to the harness as usual.  The Munter is only used to protect a factor 2 fall; once good pro is obtained the belayer dumps the Munter and belays with the gadget on their harness as usual.  This means the anchor doesn't have to be rigged for an extreme upward pull and also the rigging can be (and should be) the usual load-distributing style rather than the direct belay styles illustrated by the OP.  Unlike generic direct anchor belays, this system can be used with half ropes, since the need for them to run independently doesn't occur until protection is obtained at which point the belayer switches to a harness belay.

curt86iroc wrote: Meh, to each their own I suppose. Call me old fashioned, but I like some load sharing properties in my anchors...

The series connection is the result of the studies of different anchor setups under dynamic loads in multi pitch style conditions. The resources linked by the OP are a good example. Unfortunately, I don't know of any in English.

The main reasons for favoring series connection for solid anchor points were: that load distribution is not so good under dynamic loads; extension in case of failure of a point was worse than shifting the load to another point; belayer displacement is dangerous for their safety and increases load on the anchor; it's the easiest way to retain the multi-directionality of an anchor point.

In my example, distributing the load wouldn't make much sense between a shiny, new, tight bolt and an old, rusty pin (albeit solid when I tugged on it). So I load the bolt and in the unlikely case of its failure, there is a back up for it. What if the backup is not strong enough? exactly! then why load it at all in the first place? What if the bolt is bad for some reason that can't be checked visually? For that remote case there is a backup...
 Notice the failure would be most likely for a downward pull (fall directly onto the anchor). Upwards pulls wouldn't be nearly as strong (friction at the top piece).

rgold wrote: A hybrid strategy---admittedly specialized---with ordinary gear anchors is to install a Munter on the anchor, pull up a bunch of slack---enough for the leader to reach good protection---and at the end of that slack install a belay gadget clipped to the harness as usual.  The Munter is only used to protect a factor 2 fall; once good pro is obtained the belayer dumps the Munter and belays with the gadget on their harness as usual.  This means the anchor doesn't have to be rigged for an extreme upward pull and also the rigging can be (and should be) the usual load-distributing style rather than the direct belay styles illustrated by the OP.  Unlike generic direct anchor belays, this system can be used with half ropes, since the need for them to run independently doesn't occur until protection is obtained at which point the belayer switches to a harness belay.

So you assume the first piece they place is solid? And so undo the Munter, maybe leave the anchor clipped?

Or wait until the leader says "this one is solid for sure" at piece n? Then an upwards pull may or may not happen in case of a fall before piece n.

One should also think, when is a bolt going to fail? Not because the load exceeds 22 kN, that won’t happen. It fails when there is something wrong with the bolt or the rock. Then it’s nice to have a backup.

A 90 degree swing on a nearly tight sling is not a shockload like a ff 2 on static. 

curt86iroc wrote: Meh, to each their own I suppose. 

Well, I wasn’t claiming the setup is good or bad, just that your concern for one photo should have been the same for all photos. 

Call me old fashioned, but I like some load sharing properties in my anchors...

Yes, most of us like the idea.  But test after test shows, even after the best attempt to load share, very little takes place even from the tiniest offset from the anticipated direction of loading. 

So the op’s setup forgoes load sharing for advantages already mentioned by others. 

The reason Europeans place the bolts vertically is to avoid extension and shockload as much as possible in this series connection with one loaded and one backup bolt. I don’t know why the Americans favor horizontal placement. 

Kees van der Heiden wrote:I don’t know why the Americans favor horizontal placement. 

I can think of some dirty jokes that would explain the Americans. ;)  (speaking as an American.)

More seriously, that mind set may be changing. I see more and more placed vertically, especially rap anchors..

Fran M wrote:

So you assume the first piece they place is solid? And so undo the Munter, maybe leave the anchor clipped?

Or wait until the leader says "this one is solid for sure" at piece n? Then an upwards pull may or may not happen in case of a fall before piece n.

Yup, there is an issue with the first piece being good with this system.  It works best if the party can see that pro will be good after a crux near the anchor, otherwise judgement is called for.

Thanks for all of the replies everyone. I have read everything posted, and taken a number of different pieces of advice that I will incorporate.

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Fran, I would like clarification on one of your points:

"In case D, If you shortened the sling with an overhand for the backup and then clipped your self to that loop, you messed up. The sling shouldn't be loaded but on the loop at the master point."

Do you mean that the the sling going to the backup bolt should not be taut?

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and also Bill Lawry:

"Eli,  Just a point of clarification: When you say "as in C - belayer attached on right", you mean attached on the right side of the anchor but on the left of the two non-bolt biners.  Yes?"

In C, I meant for the belayer to be cloved into the lowest biner in the photo. Does it matter if the belayer is there, or on the backup (left) bolt, as in D? It seems like the belayer being attached to the main (right) bolt may serve to reduce the force on the backup bolt if the main bolt fails.

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With regard to ring-loading of the master point (mentioned by a few), does it really matter if I use a knot that can capsize such as an overhand or figure-8? Even if it does capsize, it will not roll itself apart. The loop will enlarge a bit is all.

Eli 0 wrote: "Eli,  Just a point of clarification: When you say "as in C - belayer attached on right", you mean attached on the right side of the anchor but on the left of the two non-bolt biners.  Yes?"

In C, I meant for the belayer to be cloved into the lowest biner in the photo. Does it matter if the belayer is there, or on the backup (left) bolt, as in D? It seems like the belayer being attached to the main (right) bolt may serve to reduce the force on the backup bolt if the main bolt fails.

You raise a good point - that the belayer's weight can act as a counterbalance for a lead fall.  But this is mainly after the first piece has been placed?

More generally, I'm still pretty new in my thinking about this config.  So I'm not the best person to generically recommend one way or the other.  But my gut is to have the belayer on the right bolt for the reason you brought up.

With regard to ring-loading of the master point (mentioned by a few), does it really matter if I use a knot that can capsize such as an overhand or figure-8? Even if it does capsize, it will not roll itself apart. The loop will enlarge a bit is all.

I'd choose the knot that is better for the fall forces acting on ring loading.  Intuitively, I suspect that the bowline on a bight is such a knot compared to an overhand or figure 8.

Of course, some knots are not practical to tie in the middle.

Greg D wrote: Well, I wasn’t claiming the setup is good or bad, just that your concern for one photo should have been the same for all photos. 

 In the photo, the sling connecting the bolt to the pin has obvious slack in it and is dyneema. I would have less of a problem if the slack was removed AND a rope was used as in the OPs images A and B.