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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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Crag Q
Trad climber
Louisville, Colorado
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Jan 18, 2007 - 01:36pm PT
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Hi Goclimb,
It's obvious you're spending a lot of time thinking about this and looking for new answers to old problems. I respect that. I really enjoyed Largo's new anchor book because it challenged a lot things I held as truths, most of which I had gotten from the previous 2 books.
Anyhoo, you got me on the knots. There's more in the equalette. 2 limiters and 2 clove hitches.
I was getting ten biners because on a mutlipitch climb you'd have an anchor atop pitch one, and another a top pitch two. So, you need gear for 2 anchor setups.
Here's how the inventory racks up for one 3 piece anchor:
mooselette: 1 cord, 5 biners, 1 locker on power point.
equalette: 1 cord, 3 biners, 1 or 2 lockers on power point depending on whether or not you do a sliding -X between the limiter knots.
cordolette: 1 cord, 3 biners, 1 locker on power point.
How's setting up the mooselette in the dark when you're cold, tired and dehyrdrated? I like to keep my systems as simple as possible, so when I'm in that situation I can do the exact same thing I do under ideal conditions.
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Crag Q
Trad climber
Louisville, Colorado
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Jan 18, 2007 - 01:44pm PT
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Another disadvantage that just occured to me with this mooselette is that it doesn't work with 2 anchors. So, you'd have to have a different process for a 2 piece vs. 3 piece anchor. Not to mention when the gear is crap there's also the need to equalize 4 pieces which is no problem for the equalette or cordolette. It's the same process.
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the Fet
Knackered climber
A bivy sack in the secret campground
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Jan 18, 2007 - 02:22pm PT
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The horse is alive and kicking, and some of us enjoy the ride...
I believe the testing showed a small amount of extension was ok (e.g. in a limited knot sliding X). But I would be concerned about a lot of extension (e.g. in a 48" sling sliding W) where the anchor could drop feet instead of inches (and the rope tie in may be short), and also the possibility of being pulled of the belay ledge. So I wouldn't use a sliding W (built with a long sling/cord) without some sort of backup to limit extension. You could always back up the sliding W with a cordelette tied with a single knot or as an equalette, or make the sliding W out of a 1 foot sling with extensions to the pieces (if you really required equalization on 3 sketchy pieces, I would't want to be there :-).
I started using the cordelette with a knot when I became aware of it because I thought it was the quickest, simplest way to build a 3 piece anchor that at least partialy equalized. I used it perhaps 90% of the time. The slidingX thread (due to input from Largo's book) let me know it doesn't equalize. So personally I looked at the sliding X thread as an attempt to find a replacement.
Perhaps there may be a great idea that comes along and solves all the requirments: equalizes 3 pieces, simple, fast, redundant, uses small amount of normal gear. But I think the sliding X thread demonstrated that there are solutions that can do everything but be KISS (simple). I posted the only design on that thread (under username Glowering) that placed equal loads on 3 pieces (33%/33%/33%)(neglecting friction) limited extension, and equalized, and although it was quick and simple for me to setup, I realized it wouldn't be so for the average climber.
One of the primary goals of equalization IMO is load sharing. You don't need exactly the same force on every piece, but if you have a pretty good split between two pieces you've given yourself a much greater margin of safety.
In looking at the equalette I saw a design that does a good job at equalizing on two pieces with 1 or 2 more in backup (i.e. only weighted if primary fails) pieces (that's what I need 90% of the time). And it's pretty simple. However I don't like the idea of tying two or more correctly positioned clove hitches at each anchor (a little time consuming), so now I use a sliding X with limiter knots (pretied) as my primary anchor, load sharing on my two best pieces, with 1 or two seperate backups if needed. I now use this 90% of the time, so basically it's my cordelette replacement. I can set it up faster than anything (besides the cordelette with a single knot) and it's simple enough for all my partners to easily understand.
The possibility of the clutch effect Largo notes above (binding in a slidingX powerpoint causing loss of equalization) can also be mitigated by tying one of the strands between your limiter knots (in a sliding X or equalette with limiter knots) a little longer than the other one. This keeps the strands from interfering with each other. I use a big locking biner for my powerpoint, (which Largo points outs reduces the clutch effect)but I prefer the big end down so I can clip multiple biners into it.
Crappy photo, but hopefully gives the idea:
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GOclimb
Trad climber
Boston, MA
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Jan 18, 2007 - 02:53pm PT
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Another disadvantage that just occured to me with this mooselette is that it doesn't work with 2 anchors. So, you'd have to have a different process for a 2 piece vs. 3 piece anchor. Not to mention when the gear is crap there's also the need to equalize 4 pieces which is no problem for the equalette or cordolette. It's the same process.
The mooselette works with three or more pieces of gear. For fewer than that, no gear shenannigans are necessary. I'd just use a pair of quickdraws, a crossed sling, or the rope, for two pieces (depending on what they were and the configuration). And just a locking biner for a one-piece anchor.
I'm not interested in being the advocate for the Mooselette. It has serious disadvantages that haven't been mentioned here. But so does just about everything, *especially* the old cordelette.
Yes, I put some thought into this the first time around, and I've put some time into using a few of these configurations in the field. I don't mind discussing my findings here - that's one of the things these forums are good for.
GO
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raymond phule
climber
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Jan 19, 2007 - 05:18am PT
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"I believe the testing showed a small amount of extension was ok (e.g. in a limited knot sliding X)."
I believe that the tests where done without anything in the place of a belayer so the test actually doesn't show anything about shock loading if a belayer is included in the belay chain.
The test show that no shock loading occurs due to the falling climber. This is not strange but wasn't well know before.
A falling climber plus "falling" belayer due to extension is definitely going to load the ancors in a different way compared to just a falling climber (as in the test).
The force from the climber might be less due to slipping in the belay device.
The falling belayer is going to load the anchor independent of the falling climber. This load is going to be higher with a stiffer connection between belayer and anchor. 10 cm of climbing rope is not much to soften the connection.
edit: The term shock loading is not god here as rgold pointed out in the other thread. All dynamic forces on a anchor could be considered shock loads. The interesting question is simple if the load is going to be very high if extension happens.
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tito
climber
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Jan 19, 2007 - 06:29am 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
one should hope for nothing of the kind. if you had had your way, the whole thread over there would have been killed after 3 posts as people succumbed to your demands that they first read all the past threads on anchor building and JL's book 1 and book 2.
As someone pointed out, a fall of factor 2 is highly unlikely. Redirects and practicing a "soft belay" in the event there is a possibility would seem to mitigate the risk even further.
a factor 2 fall does not produce double the force of a factor 1 fall. a factor 2 fall increases the force on the anchor by 40%. redirecting the belay through the anchor increases the force on the anchor by around 60 percent. if you are concerned about reducing the forces on the anchor, redirecting the belay does not get the job done. the goal is not simply to reduce the fall factor. reducing the fall factor only slightly by redirecting the belay through the anchor will increase the forces on the anchor by almost 60%(catching a fall directly on your waist v. redirecting the belay through the anchor).
other issues come into play as well. can anyone catch a factor 2 fall on their waist? without gloves? or will there be so much slippage through the belay device that the belayer will drop the climber?
I’ve used it [ed. two sliding x's with limiter knots to form a three piece anchor] on many occasion and with the quad as per Largo’s book it seems like a perfectly reasonably anchor, am I missing something?
a majority of force goes to the shorter leg? because it stretches less when the anchor is impacted? that's not a bad thing. if the force were equally distributed to both arms, the force distribution to the three pieces in your picture would be 50-25-25. if 60% of the force goes to the shorter leg, then you could have something like 40-30-30(if the 60% going to the shorter leg was then equally divided between the other two pieces--but once again leg length of the rigging between those two pieces matters). note the better distribution of forces: 50-25-25 vs. 40-30-30. you just have to be aware of that unequal force distribution. when one leg is shorter than the other, you have to be careful not to rig the anchor in such a way that you put 60% on a single marginal piece, which could happen if you had the shorter leg going to one piece. then you would get a distribution of something like 60-20-20, which is worse.
Briefly, my preference goes from top to bottom, with the Mooselette equalizing the best
from looking at that rigging, it doesn't seem like it can equalize well because of all the friction produced by so many strands of cord running across biners. hooking up a portaledge to an anchor and being able to get a good night's sleep does not prove that an anchor is reliable for trad climbing. unless you have test results that show otherwise, one can only assume that anchor won't equalize very well. the more strands of cord running around biners, the harder it is for an anchor to equalize. the two sliding x's with limiter knots would appear to be superior.
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raymond phule
climber
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Jan 19, 2007 - 07:44am PT
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Is it possibly to get any details about John's testing except from the book?
The things I have heard about the test and the results don't quite add up.
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wootles
climber
Gamma Quadrant
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Jan 19, 2007 - 08:29am PT
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What isn't adding up?
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Ed Hartouni
Trad climber
Livermore, CA
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Jan 19, 2007 - 08:42am PT
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It would be nice to have a technical paper desribe the results, with quantitative data, so that others could analyze the tests. I don't know what journal they could be published in, but that would be great if it were possible.
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raymond phule
climber
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Jan 19, 2007 - 09:00am PT
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The test was done with 2 anchoring points, right?
It is often stated that using a cordalette put all force to a single anchor if the legs are uneven in length. This cant be true in general if the anchor points are spaced horizontially apart. The configuration is more important than the lengths of the arms.
The understanding (after reading parts of the threads) of the result of the test seems to go outside what was actually tested.
Some examples.
The above example.
That the equallete equalise 4 points.
That no shock load (high load) happens in a real situation with a belayer.
That the cordalette is bad with 3 points (probably correct but not tested)
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jstan
climber
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Jan 19, 2007 - 09:06am PT
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I must be missing something. We all realize no two anchors have the same strength and we count on our ability to estimate this strength. Why are we trying to equalize the load??
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SuperTopo on the Web
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I was a fairly enthusiastic participant in the rc.com thread and there is tons of good stuff in it - I did nothing to attempt to quash it. 
Let us know!