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healyje
Trad climber
Portland, Oregon
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Jan 17, 2007 - 10:59pm PT
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Rags, have you read the entire rc.com sliding-x thread? One would hope any discussion here would use that as a starting point versus attempting to cover all that ground again. Comments about the wisdom of doing so here have to do with the seemingly unavoidable landmines of various stripes this topic has invoked at both sites. In my opinion, anyone really committed to such a discussion who hasn't read the rc.com thread in its entirety ought to consider doing so before starting in here in order to understand the lay of the land and the reason for statements of caution.
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Ed Hartouni
Trad climber
Livermore, CA
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Jan 17, 2007 - 11:05pm PT
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I find a perlon cordolette a sweet piece of gear and carry it, and use it, in many situations. I am fully aware of it's limitations and apply it in situations that I think are safe. It is a quick way to setup an anchor.
I have also used the same system as healyje on occasion, tie off on the high piece with a clove-hitch, tie into two lower pieces via a "magic-x"... equalize the clove-hitch and you're good to go.
It also helps to pick a good belay spot appropriate for the gear you got rather than put some jingus pro in an arbitrary place. When I'm leading I'm always looking for the belay spot...
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Rags
Trad climber
Sierra foothills, CA
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Jan 18, 2007 - 02:54am PT
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healyje,
yes I was reading along for quite a while when the thread started. Maybe a review isn't a bad idea. It is possible that I am asking something that may have been answered before. So are others. Isn't that what started this thread?
Restating and reinforcing updated information is exactly what needs to occur for MYTHS, such as the one I quoted from ASCA to be dispelled. In fact, there is other value in reviewing information. The review process often sheds new light that reveals unexpected results. Now I've gone and done exactly what I criticzed, a post of marginal relevance to the topic.
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v10gripper
Boulder climber
Joshua Tree, CA
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Jan 18, 2007 - 03:40am PT
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I'm not going to sit here and read all of the posts in this topic, so this may have already been said.
I have switched out my static cordelette with dynamic cordelette, this aliviates(sp?) some of the factors in a "what if" situation. I think that this helps out both scenarios(sp?) the sliding "w" and the "figure 8" at the "power point". I use a peice of a twin rope. I would bet in the next couple of years you are going to see just about all manufactures(sp?) marketing some sort of similar(sp?) product just for equalizing(sp?) anchors.
sorry about all the"(sp?)'s" but I have had too much to drink to spell properly, or for that matter care that much.
S.Powers
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Degaine
climber
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Jan 18, 2007 - 04:37am PT
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My apologies for continuing the flogging of this dead horse, but I find the discussion interesting and have a couple of comments/questions.
1) I really like this setup:
I’ve used it on many occasion and with the quad as per Largo’s book it seems like a perfectly reasonably anchor, am I missing something? I don’t use it all the time, and like a good Marine I improvise, adapt and overcome depending on the situation.
Goclimb, I can set it up pretty quickly, what is it exactly that you don’t like or what takes you so long?
It’s ironic that the setup you consider to be so quick, I (and apparently a few others?) consider to be complex or time consuming. Guess it’s just a matter of practice and familiarity, right?
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healyje
Trad climber
Portland, Oregon
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Jan 18, 2007 - 04:52am PT
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"I'm not going to sit here and read all of the posts in this topic, so this may have already been said...."
And so it begins...
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wootles
climber
Gamma Quadrant
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Jan 18, 2007 - 07:09am PT
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To GO and others who may have been offended by my 'impertinent' statement. I apologize for being so general. I was referring to the vile ugliness that erupted in a couple of the threads on this topic at rc.com. Ultimately there was more positive discussion and great ideas than impertinence.
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raymond phule
climber
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Jan 18, 2007 - 08:36am PT
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"if you are tied to the anchor with a dynamic rope there is no shock loading."
Everything doesn't seem to be clear yet...
The problem as I see it is about shock loading and the belayer. I dont think the above statement is correct in general, the loading on the ancors depends on the length of dynamic rope between the ancor and the belayer. This lengths could be very short when for example using a cordallete. I believe that I sometimes clip the biner directly into the rope tie in loop (not the harness tie in loop).
The logical step I have seen several times and dont agree with.
Extension is bad if the connection belay belayer is static but it doesn't pose any problem if you have the rope in the chain between belay and belayer.
This is true if the extension is much less than the connection rope. I dont belive that this is always the case and the statement is false otherwise.
Have someone done any testing of the loads on the anchor that also inlude the belayer?
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Largo
Sport climber
Venice, Ca
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Jan 18, 2007 - 11:08am PT
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Degaine--
That set up is bomber so far as the individual placements are bomber. A common misuderstanding is that the rigging determins the holding power of a given anchor. The rigging can only exploit the potential holding power of the individual placements, nothing more.
An interesting side note to the above anchor (the Degaine pic) is that in testing, were were aware of the so-called "clutch effect" that sometimes happens in the Sliding-X and other systems were rope strands are running over in a way that can bind on the biner. Wottles found that by using a big, pear-shaped, anodized biner, with the mouth on top, gate faced outwards, the clutch effect was largely if not entirely eliminated. This is really a point worth noting because it makes a huge difference in the degree of load sharing in an anchor.
JL
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GOclimb
Trad climber
Boston, MA
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Jan 18, 2007 - 11:30am PT
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Degaine,
The pair of sliding-exes is indeed a fair setup. You asked if you are missing anything. I really don't know, as you didn't state the pros and cons as you see them.
Here they are as I see them. I'll take the three-point anchor just for clarity's sake, though all the pros and cons apply for two- or four-point anchors, too:
Pros:
1 - Shares load between all anchor points
2 - Easy to understand and inspect
3 - Requires fairly small amount of gear (one long sling, one short sling, and one biner)
4 - Is fairly resistant to cutting of slings (say by a falling rock). The only point that, when cut, will cause the entire anchor to fail is the small area between the knots at the power-point.
Cons:
1 - Even with no friction, one of the pieces gets half the load, while the other two each get a quarter.
2 - Requires tying, untying, and adjusting four knots.
3 - In testing, the sliding-x has been shown to sometimes bind on itself (the two strands are moving in opposite directions at a pretty good clip), so the dynamic equalization potential is limited.
For reference, here's the pic of the setup Degaine is referring to:
GO
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v10gripper
Boulder climber
Joshua Tree, CA
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Jan 18, 2007 - 11:33am PT
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""I'm not going to sit here and read all of the posts in this topic, so this may have already been said...."
And so it begins... "
and so it ends
S.powers
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GOclimb
Trad climber
Boston, MA
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Jan 18, 2007 - 11:49am PT
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Degaine said "It’s ironic that the setup you consider to be so quick, I (and apparently a few others?) consider to be complex or time consuming. Guess it’s just a matter of practice and familiarity, right?
It is indeed. I now carry my cordelette with those two knots in it already, so all that's required is that I clip the cord into the three pieces, pull the middles down to the power point, adjust the two knots, and I'm done.
By the way, the mooselette doesn't only work as I showed it earlier, with all three pieces lined up nicely in a horizontal. Here's a pic of it where all three pieces are spread out over three dimensions. Note that the foreshortening of the camera angle makes it look like there's a high angle in the cord on the left side, whereas it's really just that the tricam is buried in a rather deep crack.
GO
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G_Gnome
Boulder climber
Sick Midget Land
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Jan 18, 2007 - 11:57am PT
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Damn, I read this whole thread. Anyway, GO I have a question about your last photo.
Would it not be a lot better to have the tied off loop that the central piece is clipped to be much smaller such that the 2 other pieces are clipped in an upward direction so that if one of the side pieces blows the extension is greatly minimized? Seems you could just about eliminate that extension in this case yet you didn't bother to. Are you missing this factor?
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v10gripper
Boulder climber
Joshua Tree, CA
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Jan 18, 2007 - 11:59am PT
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"Damn, I read this whole thread"
That was dumb
S.Powers
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Degaine
climber
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Jan 18, 2007 - 12:07pm PT
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JL and GOclimb, thanks for repsonding to my question!
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Crag Q
Trad climber
Louisville, Colorado
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Jan 18, 2007 - 12:20pm PT
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One of the disadvantages of the mooselette that I can't get over is that it uses 2 more biners than the equalette. So, that's 5 biners instead of 3 (not counting the locker). In a multipitch situation that's 10 biners being used up just rigging anchors (not counting the lockers).
It also appears to be a tad more complicated to setup than a cordolette or equalette based on # of knots tied and biners clipped. It seems that evaluation how your pieces are being loaded would be hard to determine because the extra biners change the direction of the forces.
It might be perfectly great, but I'm going to file the mooselette under "interesting, but no thanks."
K.I.S.S
my $0.02
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GOclimb
Trad climber
Boston, MA
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Jan 18, 2007 - 12:52pm PT
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g_gnome: Would it not be a lot better to have the tied off loop that the central piece is clipped to be much smaller such that the 2 other pieces are clipped in an upward direction so that if one of the side pieces blows the extension is greatly minimized? Seems you could just about eliminate that extension in this case yet you didn't bother to. Are you missing this factor?
To answer that question, I first have to explain how this system extends. Most of the extension goes into re-equalizing the system. So, lets say that right-hand piece is nine inches above the knot. If it rips, the power point only will extend one third the distance, or three inches. So by moving the knot up a few inches, it doesn't change much. I don't mind having three inches of extension in the system.
But why have those three inches at all?
Because if I were to move that knot all the way up, the angles caused by the outer pieces linking to the biner get pretty high. It looks a little like an American Triangle when I do that. I'm not convinced it loads forces like an AT, but, barring testing, why risk it?
GO
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HighDesertDJ
Trad climber
Arid-zona
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Jan 18, 2007 - 12:54pm PT
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Yeah I can't imagine I'd ever use that in real life.
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GOclimb
Trad climber
Boston, MA
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Jan 18, 2007 - 01:07pm PT
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crag_q, if I understand it correctly, a three-piece equalette requires four knots and two locking biners (not counting the biners on the gear), while the mooselete uses two knots and three biners (only one being a locker). Certainly a tradeoff. Not sure how you got to 10!
Anyway, there's are pros and cons to each - no doubt about it. I have played around with them enough so that I think I understand them as well as I can without subjecting them to drop tests with load cells (I wish!) And I've been quite happy using a few of them in all the scenarios I've been in.
But it would be great if more people became familiar with them and played with them on their own. Given all the creative minds out there, I bet we could at the very least stimulate some worthwhile discussions, and at best, come up with a simple hybrid that nearly everyone can love and use. Just be careful, and make sure you know what you're doing before you hang you and your partner's life on it.
GO
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GOclimb
Trad climber
Boston, MA
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Jan 18, 2007 - 01:11pm PT
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The CharlesJMM anchor is extremely simple, doesn't use any extra biners, and is safe against cord breaking/cutting.
GO
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