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crusher
climber
Santa Monica, CA
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Jun 18, 2009 - 02:43pm PT
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Greg didn't you and/or Alan replace/add new anchors at Clark? At any rate my point being as far as I know nothing at Clark was retro'd by people who didn't know what they were doing.
I think I know what the OP is talking about in terms of the remaining open anchor hooks there - they're not bolted into the rock so tightly as to not swivel inward some when threaded for a rap or a lower off. I've never personally been concerned with them but to each his own, take a look and make your own determination.
I think the musseys are fine...last person to climb can lower off of them or rap off - they're set like they are in The Gorge.
The most recent Mammoth Area guide book (Marty Lewis) has section on Clark Canyon if anyone wants to read about the gear there.
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Largo
Sport climber
Venice, Ca
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Jun 18, 2009 - 03:28pm PT
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I've driven myself half mad in these kinds of discussions. Ultimately, I've found it useful to consider every anchor in terms of two factors: a) the known or calculated reliability of the primary components in the anchor array, and B), how said components are linked or rigged together.
In other words, the primary anchors (bolts, nuts, pegs, cams, et al) and the rigging (chains, shuts, slings, etc.).
General rule: The sketchier the primary anchors, the more important it becomes to consider SRENE rigging strategies.
Two bomber, 3/8" bolts set in diamond hard granite and you can tie them off most any which way and the thing will likely hold fast. Start working with wires in horizontal cracks, sketch rock, etc., and no-extension, equalization and so forth become meaningful, even life-saving (though rarely, IMO).
Another thing, anytime you're using inflexible chain to connect two bolts, it's very dificult to build the set up so loading is somewhat equally distrubted betwen both bolts. And even if things are "perfect," off-axis loading will put most if not all the weight on one or the other bolt. With good bolts is good rock this is almost certainly not a factor. Move onto choss and it's almost always better to use nylon, even if you need to leave something behind.
JL
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pimpdaddy
climber
manchester, vermont
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Jun 18, 2009 - 03:46pm PT
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The anchors that have been replaced in Clarks are fine.
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HighDesertDJ
Trad climber
Arid-zona
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Jun 18, 2009 - 03:56pm PT
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The anchors at Clark's Canyon have been how the OP describes for at least 12 or so years. There is a huge difference between your rope through hooks like that and an American Triangle. It is true that it increases the forces, and it is probably not the ideal setup but so long as the bolts are solid and the placements are solid there is nothing inherently unsafe about it.
The American Triangle is dangerous not simply because it increases the force (which a decent bolt anchor can easily handle when used for lowering or rappelling) but because there is no redundancy in the anchor. If the webbing fails at one spot the entire anchor fails. In a mussy hook situation if a bolt failed the other bolt will still catch you.
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Largo
Sport climber
Venice, Ca
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Jun 18, 2009 - 04:19pm PT
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He wrote: "The American Triangle is dangerous not simply because it increases the force (which a decent bolt anchor can easily handle when used for lowering or rappelling) but because there is no redundancy in the anchor. If the webbing fails at one spot the entire anchor fails."
The term "American Triangle" was originally used to describe common rap points/anchors at the top of popular climbs in Yosemite. Often times these climbs would feature two pins bashed into a horizontal crack with a shitload of slings fed through the eyes of the pins. Or else there would be two bolts on top of a short free climb, for example, Lunatic Fringe, with slings stuffed through the bolt hangers.
In both cases the sling configuration described a triangle, with downward force generating sometimes sizable inward load multiplication on the pins and bolts. If one placement blew, the slings were still fed through the other placement so only if that blew as well would the whole shebang fail.
Considering how sketchy some of these anchors were, it's amazing that more of them didn't blow. With modern sport bolts, anchor failure (anchor actually pulling out) is very rare, and is almost always due to the rigging screw ups (like not correctly girth hitching the slings together, etc.), not the anchors getting yanked out. In fact I'm not sure there's any documented case of a modern sport (bolt) anchor failing, though plenty of folks still get dropped and bungle their tie ins and tie offs.
JL
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couchmaster
climber
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Jun 18, 2009 - 04:28pm PT
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JL Said "In fact I'm not sure there's any documented case of a modern sport (bolt) anchor failing, though plenty of folks still get dropped and bungle their tie ins and tie offs. "
Do you (OR ANYONE!) know of some with old short rusty 1/4"ers that failed John?
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couchmaster
climber
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Jan 21, 2015 - 01:58pm PT
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Me either. Just the single Rawl Stud on Anchors Away that 2 people were reportedly simultaneously jugging on. In fact, I consider the "American Death Triangle" essentially a myth. Everyone uses them and they work fine. Good for internet arguments but little else.
BTW, learned a good tip from Jim Titt of DMM. If you install Fixe anchors that have the hooks, if you can install them so the hooks touch each other, it will reduce oscillation and result in less material being rapidly worn off as you rap and pull ropes: especially in gritty rock. (that's my summation, he may have a differing clarification of what he actually said)
ie, not this:
This
Pictures of my anchors, placed @ a year apart. Changed my placement strategy due to Jim Titts words. The anchor Mfg recommend 4X the diameter of the wedge anchor spacing for optimum strength, so it's a fine line to get both that and have them touch given the length of the Fixe Stainless hook anchors. By this time I'd had to retire a DMM biner which I had used for belay/rap biner on my ATC that developed a deep groove in a single day from a multiple rap down on a wet day. I figured that even though the anchors are stainless and not Aluminum, to go with his wisdom. Thus they started being placed closer together so as to optimize the material lifespan. Also, this rock did not seem to have developed fracture planes like many other rock substances do so that didn't need to be considered.
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Killer K
Boulder climber
Sacramento, CA
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Jan 21, 2015 - 02:19pm PT
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The worst part is the a$$holes you get in your rope when you lower off an anchor with the chains too far apart. And I agree tr on yer own shite.
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Camahoo
Trad climber
Dead Pine Ridge, Ca
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Aug 30, 2016 - 01:40pm PT
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This anchor is perfect!
what your not seeing in the picture, is the guys girlfriend is pregnant and she wants to keep it.
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labrat
Trad climber
Erik O. Auburn, CA
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Aug 30, 2016 - 02:36pm PT
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Wow!
Not much else to say....
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this just in
climber
Justin Ross from North Fork
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Aug 30, 2016 - 08:37pm PT
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what your not seeing in the picture, is the guys girlfriend is pregnant and she wants to keep it.
That's funny. Sorry
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scaredycat
Trad climber
Berkeley,CA
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Aug 30, 2016 - 10:51pm PT
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The anchor in d2r2's photo is totally bizarre, but it could be worse. At least it's redundant w.r.t the failure of either anchor. OK, with the same gear, it could be a whole lot better, too.
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Ed Hartouni
Trad climber
Livermore, CA
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Aug 30, 2016 - 11:35pm PT
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The classic "American Triangle"
how come they always used white slings BITD?
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Stephen McCabe
Trad climber
near Santa Cruz, CA
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Aug 31, 2016 - 01:26am PT
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Don't know if it was a serious question. However, many didn't start out white, but became white after too long in the sun. See the blue where it was shaded?
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Ed Hartouni
Trad climber
Livermore, CA
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Aug 31, 2016 - 10:47pm PT
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ahhh, serious question... I thought this was a RC.noob thread! so I put in the question...
but maybe the humor was a bit too wry...
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