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I generally use the Joshua Tree anchor system for toproping, as taught to me by a professional guide. Essentially, a static rope is tied to two anchor points to make a "V" shape of 90 degrees or less. If the angle is greater than that, less and less force is shared between strands.

I came across a climb I want to try where the only natural anchors are trees far to the left and right of the top of the climb. If I used a tree from each side, the angle of the rope would exceed 90 degrees. If I used two trees from one side, the direction of pull would be wrong. Bolting an anchor isn't an option in this area.

Is there a reasonable way to set up an anchor here so that I'm not putting a nearly full load on both strands? The only thing I can think of is to use two independent J-Tree systems (a "V" on each side). The two systems as a whole would have an angle greater than 90 degrees, but each side would be almost twice as strong. Is there a better way?

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  • John Long has arguably the definitive book on climbing anchors: amazon.com/Climbing-Anchors-Climb-John-Long/dp/0762782072/…
    – noah
    Jan 31, 2023 at 1:58
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    Physics is physics. Far apart anchors just don't really work. Best I can think of is... well, find other anchors. Sounds like a potential use case for cam based anchors depending on the specific rock. If this is the direction you go, please learn trad anchors in-person from a qualified/experienced climber, not just from internet forums.
    – noah
    Jan 31, 2023 at 2:05
  • I have that book. I couldn't find anything in there that answered my question. There are not any decent placements at the top of the climb for a gear anchor either. The tautology isn't really helpful. I figured someone might have thought of something for this particular scenario. Sometimes there are non-obvious solutions to these kinds of problems.
    – SamWeiss
    Jan 31, 2023 at 4:23
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    just how far apart are these trees? You can always bring a longer static rope.
    – IMil
    Jan 31, 2023 at 12:02
  • Even with 140°, the force is 146% on each anchor. If top rope falls are <4 kN, that's 6 kN per rope/tree, which doesn't seem like a lot. Am I missing something?
    – endolith
    Jan 31, 2023 at 21:15

1 Answer 1

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Assuming there is no option to add cams, nuts or bolts where you want, I see the following options:

  • extend the anchor so far that the angle gets below 90 degrees. This is obviously limited by the length of your slings, and you will be missing the top part
  • build the actual redundant anchor somewhere else and just redirect it at the top of your climb using a non-redundant placement
  • No redundancy. Big trees are typically considered safe enough to be a non-redundant anchor.
  • Cold redundancy. For top roping, I would prefer not to rely on a single tree as the anchor. Not so much because of the tree failing, but because of possible abrasion on slings. Therefore, I would add a cold (unloaded) redundancy to the anchor that connects the carabiner with another tree or placement and acts as a backup in case anything fails
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  • I like the idea of redirecting. That might be a possibility in my situation.
    – SamWeiss
    Jan 31, 2023 at 23:16
  • @SamWeiss just keep in mind that if you redirect the rope by a too large angle, it may put the same huge loads on the redirecting placement as a greater-than-90-degrees anchor would face.
    – IMil
    Feb 1, 2023 at 7:23

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