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jsh


Mar 14, 2006, 6:06 AM
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http://www.rockclimbing.com/...p.cgi?Detailed=70638
http://www.rockclimbing.com/...p.cgi?Detailed=70639

... as a compromise between non-extending and redundant. Note the single clove hitch at one piece.

Advantages:
- SIMPLE. It's the same 'ol stuff you've always used - one cord, two 'biners (I used a draw here for clarity - but this rig vertically self-equalizes as well).
- easy to create - it's the same start to the usual, but the outer loop gets a knot and its own 'biner. that's all.
- redundancy of tie-in point
- reduced sliding friction, by using two 'biners.
- redundant to strand failure
- when pulled to the side, two pieces equalize very nicely. The other(s) gets relegated to backup, but remain still close.
- extension is limited

Disadvantages:
- off-centered loading spreads the load between only 2 pieces. Still, an improvement on the usual cordolette + knot ; and still redundant, an improvement on the sliding-X variants.
- your comments here?


fingertrouble


Mar 14, 2006, 6:11 AM
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Re: Improved sliding x: Is it really safer? [In reply to]
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Regarding those who are jumpy about genuine equalization in the "equalette," I'm certainly one of those who's convinced that the equalette as illustrated at the top of Jake's photo compillation can't possibly achieve identical force on each of the 4 (much less 3) placements during a fall.

But my lightbulb is flickering (or it was until I poured alcohol on it). What if John Long were referring exclusively to tests done on 2-anchor rigs? That would make sense, but why would it be worth getting excited about? The only explanation I can see is that clipping the cords between the limiter knots with 2 carabiners and not using the X setup on a single biner makes things equalize more effectively during the instant that the peak fall force is applied to the anchor. Apparently the pinching effect of the 2 biners is more than offset by the elimination of cords running next to each other in opposite directions on one biner. This wouldn't be obvious to me, but it's my best guess. The cords of the sliding-X don't have to actually cross over each other, but Anything Can Happen in a Climbing Fall (TM).

If my wild guess is correct, it looks like any solution that features a sliding-X at the power point needs to be given a steely stare; things could be even worse for solutions that require sliding around small radius corners, like rap rings; things might be better if there are more strands supporting the load through the master carabiner--or worse. Cord or webbing? Yowza, what's an armchair (or Herman Miller chair) engineer to do? Judging the importance of such an effect (if there is one) would likely require sophisticated impact load testing and (shudder) statisticians. Intuition likely isn't enough. I sure hope I'm wrong.


hemp22


Mar 14, 2006, 7:17 AM
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Re: Improved sliding x: Is it really safer? [In reply to]
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craig,
your wild guess was a good one....that has been covered previously.
JL's post in your other thread gave us numbers comparing the traditional single-knot cordalette, the sliding X with limiter knots, and the equalette. For equalizing the load between 2 placements, the sliding X did better than the cordalette, and the Equalette even did better than the sliding X. And yes, he states that the numbers given were from 2-point anchors. He hasn't provided numbers for any 3 or 4 point anchor tests, but we're hoping that he is doing some testing on those as well
So, the data does suggest that the friction of the 2 strands rubbing against each other does inhibit perfect equalization in the sliding X. It seems to me that this effect would get worse with each additional strand that you add - i.e. a 3-point craig short would probably get more friction than a sliding X, and 4-point craig short would get even more still. (but yes, they'll probably still be significantly better than the traditional single-knot cordalette). (link)


papounet


Mar 14, 2006, 11:56 AM
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Re: Improved sliding x: Is it really safer? [In reply to]
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In reply to:

Edit: hmmm.... seems this is more or less equivalent to papounet's idea on the previous page.

It is !

The reason I have gone with cord rather than sling to create the keeper functionnality of the sliding biner/rap ring on the 2 majors legs is: I am more confident with tying cord on cord rather than sling on cord.
I have considered using friction knot (prussik/machard..) to connect the keeper cord to the main leg cord but went for single length cord and fig-8 as we have less material in the way both when usin,g and when carrying the stuff.
Which leads me to say: although your schema is clearer, and perfectly adequate for someone recreating it from scratch with slings and biner available, I prefer the cord and rap rings.


I do not mind having to pre-build a anchor system (in fact I almost prefer doing it) well in advance: dressing the knots, color coding and the like ...
with the following goal in my mind: a KISS at the time of usage

2 pieces, slap it, connect this and that, done
the situation calls for 3 pieces, ok place them, slap it, connect , done
uhuh, 4 pieces for peace of mind, ok slap it, connect, done

(I expect to be flamed by some for having written this, but IMHO it is not while setting the belay that one has time, nor brain power to spare. It is experience that allows the climber to select rapidly which setup will fit the situation. Rehearsing of which anchor system to build together with having pre-rigged setup is a good way to supplment that experience.


papounet


Mar 14, 2006, 2:24 PM
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Re: Improved sliding x: Is it really safer? [In reply to]
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this excellent design by mhabicht

http://www.rockclimbing.com/...p.cgi?Detailed=70552

led me to realize this Equalizer with 2,4 meter of cord and 2 rap rings.
Concept: fully equalize and reduce maximum extension by limiting the total amount of material (thanks rgold for the idea of isolating the functions)


http://img81.imageshack.us/...efinitive13fo.th.jpg


http://img81.imageshack.us/...1/definitive28ng.jpg

http://img57.imageshack.us/...1/definitive37bv.jpg


It meets all my criteria for a anchoring system:
- distributes load on 2,3 and 4 pro
- resist failure : be it of a connection or or pro
(if a pro blows on a side where there is another pro, maximum extension of the rapring worst case =total length of the outside of the loop divided by 2, of the anchor 50% of that, typical extension if slidder centerd= half again those value
(if a 3rd pro on a single side blow, maximum extension = total length of central loop divided by 2), from which we can compute the optimal position of the limiter knots: they should be around 1/3 and 2/3position)
- use weak material (such a 7mm nylon) only in doubled loop
- easy to setup
- light and tight
- cheap

Cons:
May equires additional material (slings, draw, biners... to extend the pro toward the equalizer
the longer the cordalette, the more potential extension (=1/4)
this 2.4 m length was found to be ok, but a 1.8m would probably work better (less bulky, less weight, less extension, still requires no connectors for simple anchors setup (such as 2 bolts). 1.2 meter would be true to the equalizer concept, but would alway require additional connectors

I am not fully happy with the position of the rap ring. I will revisit mhabicht' s idea and experiment with other limiter knots.
I have not looked into the interaction of the biners and the rapring in case of failure
I am not happy with the position of the knot (which will be a double fisherman in a true setup and not a singe as in the pic)


in case of failure
http://img57.imageshack.us/...29/definitve43dt.jpg

in case of setup with 3 pieces, it is probably best to not use the center leg as the odd leg as the angle multiplication increase the force on the uter pro (without diminishing the force on the center pro)

http://img129.imageshack.us/...definitve53yx.th.jpg

it works also in vertical placement
http://img221.imageshack.us/...efinitive68gs.th.jpg

In case where extra reach is needed, the sliding rings can be left unused and the Equalizer then behaves like the Equalette of John Long.
http://img105.imageshack.us/...efinitive75pe.th.jpg

I am feeling quite happy about this.
If my entry behaves at least as well as the newest contender and offer new functions (which by the way are even better) at the cost of 2 rap rings, isn't this design superior ?


8^) 8^) 8^) (<-is this a smug icon ?)


guavajelly


Mar 14, 2006, 5:09 PM
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I like the looks of this one. The extra gear is fairly minimal,
I'm going to set this one up today. Nice job.

And kudos to RC.com as a new member this has been a fascinating and much needed discussion!

adam


tradklime


Mar 14, 2006, 5:47 PM
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In reply to:
I am feeling quite happy about this.
If my entry behaves at least as well as the newest contender and offer new functions (which by the way are even better) at the cost of 2 rap rings, isn't this design superior ?

It's good for 4 pieces but not as good for 3.

I really prefer the function of the 3 foot Trango Alpine Equalizer to all of the rigs presented in this thread for 3 pieces. The problems with the Trango AE are that it is a specific piece of gear and the sling is not redundant.

To rememdy these problems I think you could tie your own with cord, ala healyje's design, only double up the cord for redundancy. I would probably use 6mm cord since it would be doubled up and would use rap rings instead of biners. The rig would be pre-tied but could be untied if you needed to use the cord or the rings.

Are solid aluminum rap rings available? Ones that would provide sufficient strength for this purpose? EDIT: looks like the SMC rings should be plenty, rated at 16.6 kn.


fingertrouble


Mar 14, 2006, 5:49 PM
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OK, hemp22, so maybe it wasn't a wild guess. Maybe I was just wrapping up the scattered information for the benefit of those who haven't been following this stuff with the rapt focus it deserves. Let me masticate a bit more and see what you think about these conclusions:

    [*:c6797a673e]The "equalette" isn't meant as a replacement for the classic 1-knot cordelette anchor, rather it's meant as an alternative to the sliding-X (unless you mean the special case of a 2-placement 1-knot cordelette anchor).
    [*:c6797a673e]The drawing at the tope of Jakes compilation isn't an "equalette." It merely illustrates the master point principal of the "equalette." As shown, it can't equalize 3 or 4 placements and is not an alternative to a 1-knot cordelette anchor. Trying to rationalize how it could be an equalizing anchor is a red herring.

So that leaves the question as to how much difference there is between the equalizing effectiveness of the equalette compared to the sliding-X. John sends mixed clues: on the one hand he implies the equalette "spanks" the sliding-X, but on the other hand he says it takes two guys with P-gol darn-hD's to puzzle it out. In general, we don't know how important ease of sliding to equalize leg tensions during the instant if peak fall force really is, or what designs might do best in this regard.

    [*:c6797a673e]If the difference in effectiveness of the equalette vs. sliding-X master points is a big deal in judging complex anchor designs, then all anchor proposals with sliding-X like master points should be sent to the back of the bus. Probably so also should any design that features things sliding around small radius features, such as rap rings. Measuring the magnitude of this effect appears to be out of the reach of ordinary folk. Work on anchor designs that don't use an equalette-type master point would be a waste of time. Focus should be on those that do, such as using 3 equalettes to make a 4-placement anchor.
    [*:c6797a673e]If the difference in effectiveness of the equalette vs sliding-X isn't a huge issue in the grand scheme of things, then it just goes on the list of lesser issues, after the main criteria of equalization under load, limiting extension, and ease of construction and checking (KISS, as John likes to say).


justthemaid


Mar 14, 2006, 5:54 PM
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In reply to:
I like the looks of this one. The extra gear is fairly minimal. I'm going to set this one up today. Nice job.

Ditto on that. Took me a second to figure it out, but it's really clever and easy. Basically adding two rap rings to John's equalette. Cool.


guavajelly


Mar 14, 2006, 6:30 PM
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I just set the up the "papounette" on the floor, will build it hanging later. But so far i like it. as tradklime states this is prerigged, which in my opiion make is equally fast if as a cordolette. Since i didn't have any raprings handy, i rigged with oval binners, i see no problem with this set up.

cheers all,

adam


healyje


Mar 14, 2006, 7:55 PM
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Craig,

Have to go to work so I don't have time to do a detailed reply other than to say you are now just spewing inaccurate disinformation in the face clearly stated test results. You further misinterpret another raft of info and data. Love the level of objectivity overall...


billl7


Mar 14, 2006, 7:58 PM
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Someone besides Craig correct me if I am wrong about these points which are based on my understanding of the contents of this thread:

* for practical purposes (i.e., as an improved anchor), the author of the equalette does intend it as a replacement for the cordelette;

* the sketch at the top of Jake's collection of rigs is an equalette;

* with enough care in fiddling with the hitches, one can distribute the load over an even number of anchor pieces (angle issues outstanding and situational);

* the equalette's bottom line is good equalization across at least 2 pieces assuming the master point biners are not up against the limiter knots;

* 2 smart guy's didn't analyze how the equalette "spanks" the sliding-X; they performed a carefully controlled experiment that reportedly resulted in showing the improvement over the sliding X;

* the likely problem with the sliding X ("clutching") is not the same things as friction of cord sliding around a biner;

Please, someone sanity check me. Bill L.


glowering


Mar 14, 2006, 8:07 PM
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I built a similar setup (to the papounette) a couple weeks ago, but didn't post it or go further with it because you are either looking a potential crossloading with biners, or a setup that is prebuilt and only useful in certain situations with the rap rings.

I don't mind leaving a rig prebuilt most of the time, but I want to be able to easily untie and use in different configurations as well. e.g. if my anchor is a large tree it must be easy to untie and girth hitch the tree.

Craig- the equalette IS a good replacement for the static knot cordelette IMO. Discussions about how each side of the equalette doesn't equalize were covered in the early part of this thread. It is in essence two static knot tied cordelettes connected with a sliding X (a big improvement over the 4 piece static cordelette for equalizing).

I like a lot of the designs presented even if I only use them once to try them, and the purpose of this thread seems to be to generate a lot of ideas to work off of. The equalette seems to be an improvement on the static tied cordelette and we are still looking for something even better. But the equalette (and quad) seems to be the only new trick in the bag that I will actually start using with any regularity.


aradia


Mar 14, 2006, 9:00 PM
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In reply to:
led me to realize this Equalizer with 2,4 meter of cord and 2 rap rings.
Concept: fully equalize and reduce maximum extension by limiting the total amount of material (thanks rgold for the idea of isolating the functions)

http://img236.imageshack.us/...ivelabeled3az.th.jpg

I've added some labels for clarity. Let's say this is made with 8 feet (approx 2.4m) of cord. Assume that the master loop X-Y is in the middle, with a length of 12 inches (two strands, thus we have 6 feet left). Let's also assume that the remaining cord is evenly distributed such that each side has 3 feet, and therefore each segment is 9 inches (A-X = 9", B-X = 9", etc). If one piece from each side blows (let's say A and D), the extension will be 18". To keep the belayer at a FF .5 one would need to be tied in with 3 feet. If the master loop (X-Y) is shorter, the extension would be longer.

If the loop was made with 6 feet (approx 1.8m) of cord, with a 12 inch master loop, that would reduce the extension in a similar scenario to 12 inches, but obviously reduces the overall ability to self-equalise over a wide range.

(Do correct me if my math is wrong =)

I've been playing with a bunch of ideas, and the more I play with them, the more I understand the geometry of these various anchors, and the more I question how feasible it is to fully equalise more than two points while limiting extension. :(


tradklime


Mar 14, 2006, 9:19 PM
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In reply to:
I've been playing with a bunch of ideas, and the more I play with them, the more I understand the geometry of these various anchors, and the more I question how feasible it is to fully equalise more than two points while limiting extension. :(

Hence the equalette.

However, the use of a shorter AE style rig as the equalizer in one of the "firewall" type designs (presented in several iterations previously) does a pretty good job. The extension of a 3 foot trango AE is about 6 inches if one piece fails. It does a good job equalizing and allows a fair bit of movement.


aradia


Mar 14, 2006, 9:56 PM
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In reply to:
In reply to:
I've been playing with a bunch of ideas, and the more I play with them, the more I understand the geometry of these various anchors, and the more I question how feasible it is to fully equalise more than two points while limiting extension. :(

Hence the equalette.

However, the use of a shorter AE style rig as the equalizer in one of the "firewall" type designs (presented in several iterations previously) does a pretty good job. The extension of a 3 foot trango AE is about 6 inches if one piece fails. It does a good job equalizing and allows a fair bit of movement.

Exactly. I really, really wanted to believe that there was something "better" than the equalette, but the more I play around with the ideas presented in this thread, and some of my own ideas, the more I realise the equalette is about as good as it gets (for its intended purpose, of course). I have a 3 foot trango AE, and I think that as far as three-piece equalisation without physical redundancy goes, it's pretty ideal. At worst, with two blown pieces, the max extension for the 3 foot AE is 18 inches minus the length of the shortest leg. Not too shabby, really, if it's paired up with extensions in a "firewall" design.

My favourites at this point are the equalette and 3 foot AE.


hemp22


Mar 14, 2006, 10:05 PM
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Edit: because since it took like 2 hours before the site would cooperate and let me post this reply, in the meantime some other people already beat me to the point of my post... so carry on, nothing new here.

First - papounet, that's a pretty cool looking idea. Like a lot of other people, I'll probably try to rig one up when I have time later today and see what I think.

In reply to:

    [*:f5a1257045]The "equalette" isn't meant as a replacement for the classic 1-knot cordelette anchor, rather it's meant as an alternative to the sliding-X (unless you mean the special case of a 2-placement 1-knot cordelette anchor).
    [*:f5a1257045]The drawing at the tope of Jakes compilation isn't an "equalette." It merely illustrates the master point principal of the "equalette." As shown, it can't equalize 3 or 4 placements and is not an alternative to a 1-knot cordelette anchor. Trying to rationalize how it could be an equalizing anchor is a red herring.

Actually, the drawing IS an equalette. That's how JL defined it. It has the ability to be set up on 2, 3, or 4 placements.
Yes, I also see the weakness that it usually won't fully equalize to all 3 or 4 placements when used in those configurations. But, it IS an alternative to the traditional single-knot cordalette. Since it will equalize between 2 of the pieces, I consider it an improvement over the 1-knot cordalette, which puts most of the load on 1 piece. (we don't need "perfect" equalization to have "better" equalization than the 1-knot cordalette)

as for your other points, I agree that for formulating a decision based on the 2-point anchor data that JL gave us, we need to decide whether the equalization differences between the sliding X and the equalette are really large enough to be a big deal. My take on it is that either a sliding-X type master point or an equalette type master point is an improvement over the 1-knot cordalette, but how to decide between the sliding-X type & equalette type may be largely situational. This is why I'm really hopeful that JL has done, or will be doing, some drop tests w/ 3 & 4 point anchors.


Partner cracklover


Mar 14, 2006, 10:36 PM
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In reply to:
In reply to:
led me to realize this Equalizer with 2,4 meter of cord and 2 rap rings.
Concept: fully equalize and reduce maximum extension by limiting the total amount of material (thanks rgold for the idea of isolating the functions)

http://img236.imageshack.us/...ivelabeled3az.th.jpg

I've added some labels for clarity. Let's say this is made with 8 feet (approx 2.4m) of cord. Assume that the master loop X-Y is in the middle, with a length of 12 inches (two strands, thus we have 6 feet left). Let's also assume that the remaining cord is evenly distributed such that each side has 3 feet, and therefore each segment is 9 inches (A-X = 9", B-X = 9", etc). If one piece from each side blows (let's say A and D), the extension will be 18". To keep the belayer at a FF .5 one would need to be tied in with 3 feet. If the master loop (X-Y) is shorter, the extension would be longer.

If the loop was made with 6 feet (approx 1.8m) of cord, with a 12 inch master loop, that would reduce the extension in a similar scenario to 12 inches, but obviously reduces the overall ability to self-equalise over a wide range.

(Do correct me if my math is wrong =)

Your math is wrong. If each of the four segments uses 9" of cord, and one blows on each side, the master point will extend 4.5", not 18".

GO


aradia


Mar 14, 2006, 11:20 PM
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In reply to:
In reply to:
http://img236.imageshack.us/...ivelabeled3az.th.jpg

I've added some labels for clarity. Let's say this is made with 8 feet (approx 2.4m) of cord. Assume that the master loop X-Y is in the middle, with a length of 12 inches (two strands, thus we have 6 feet left). Let's also assume that the remaining cord is evenly distributed such that each side has 3 feet, and therefore each segment is 9 inches (A-X = 9", B-X = 9", etc). If one piece from each side blows (let's say A and D), the extension will be 18". To keep the belayer at a FF .5 one would need to be tied in with 3 feet. If the master loop (X-Y) is shorter, the extension would be longer.

If the loop was made with 6 feet (approx 1.8m) of cord, with a 12 inch master loop, that would reduce the extension in a similar scenario to 12 inches, but obviously reduces the overall ability to self-equalise over a wide range.

(Do correct me if my math is wrong =)

Your math is wrong. If each of the four segments uses 9" of cord, and one blows on each side, the master point will extend 4.5", not 18".

GO

Each of the segments is 9" _long_. The segments are doubled, though, so they each use 18" of rope. Once again: 8 feet total. 1 foot for each of the two master point segments leaves 6 feet, 3 feet on each side of the limiter knots. Two points of pro on each limiter knot means 18" for each point. Each 18" segment of rope is doubled over (eg, segment A-X is two strands of rope), so the actual distance is 9" from the pro to the limiter knot. If you have eight feet of rope/webbing, try it. Mind you, these numbers don't take into account the length required to tie each of the two knots, but they're close enough. =)


hugepedro


Mar 15, 2006, 1:00 AM
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I believe it was glowering who first posted something similar to this many pages ago, if it was someone else I apologize. I've been playing with it a bit, and like how it performs in the lab (otherwise known as my gear room).

This is a couple 4' dyneema slings on top, and a couple 3' sewn runners on the bottom. All tied in the sort of sliding-x but not really an x configuration (not sure what the sort of X should be called, a "super-slider" perhaps?). I used 3 footers on the bottom because 4 footers were too long and 2 footers didn't have enough range of motion. 3 footers are just right, Goldilocks. I wish they made 3 foot dyneema slings.

In 4 piece mode where the pieces are grouped fairly close, it will orient to both horizontal and vertical placements:

http://i2.tinypic.com/rh5npf.jpg

http://i2.tinypic.com/rh5oad.jpg

If the 4 pieces are spaced farther apart, you just add a standard runner to 1 of the "halves" of the rig and it will go completely vertical.

http://i2.tinypic.com/rh5q90.jpg

http://i2.tinypic.com/rh5qgl.jpg

In 3 piece mode, yes 1 of the pieces takes 50% of the load. I say big eff'n deal. If I don't have confidence in that piece I will use the appropriate mitigating techniques.

http://i2.tinypic.com/rh5rgx.jpg

With a 2 bolt anchor I'll just use the bottom half of this rig, the 3' super-sliders or whatever we want to call them.

All links in this chain are 100% redundant. If any piece blows the extension is no more than a few inches. I will never have to retie any of the limiter knots, just add a sling or a draw if necessary to extend pieces. It represents what I find to be the optimization of all anchoring factors I consider - equalization, dynamic orientation, limited extension, redundant, KISS, and speed - while maximizing flexibility to rig 2, 3, and 4 piece anchors.


tumblemark


Mar 15, 2006, 3:49 AM
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Re: Improved sliding x: Is it really safer? [In reply to]
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I can't believe that fingertrouble is being made to do so much heavy lifting in the equalette anchor analysis. I'll come out of lurk mode long enough to help the poor guy out, but someone like rgold who has established a rep for knowing physics should really step in. fingertrouble is, after all, critiquing his own proposal as much as anyone else's. Maybe he started off a little sarcastic for RC.com :shock: , but he's usually correct.

So, billl7,
In reply to:
for practical purposes (i.e., as an improved anchor), the author of the equalette does intend it as a replacement for the cordelette
Who IS the author of the "equalette"? AFAIK John Long talked only about measuring a 2-placement anchor. The illustration in Jake's photo post shows a 4-placement anchor (which, incidentally, doesn't equalize), so it's unfair to tag JL with that or to use his data claims to support it.
In reply to:
the sketch at the top of Jake's collection of rigs is an equalette
Has JL ever said so? Maybe I missed it; or maybe this is just an assumption that has come to be accepted as truth. You know what they say about assumptions. Best if you could quote JL with direct reference to that illustration.
In reply to:
with enough care in fiddling with the hitches, one can distribute the load over an even number of anchor pieces (angle issues outstanding and situational)
Here is where you and healyje really miss the point(s). fingertrouble and rgold have said, accurately, that for an anchor to equalize, all the arms must be made of the same number of cords of the same length. That's clear to a lot of posters, but if you aren't one of them, search through rgold's posts and you will find a nice explanation with a picture, F's, and arrows. That means that as soon as the rope goes tight, the force will shift to the shortest cords on each of the two sides; fingertrouble gave the example that if one cord to a limiter knot was twice as long it would get half the tension. You can't chose the cord lengths, that will be determined by the places where you can get in pro. If the angle of the rope pull changes from the one you guessed at when you were "fiddling with the hitches", the force will shift even more dramatically, but maybe to different placements (flyinglow's photo show this effect). If any other anchor had this kind of performance it would be laughed out of town, which would be appropriate.
In reply to:
the equalette's bottom line is good equalization across at least 2 pieces assuming the master point biners are not up against the limiter knots
*Only* 2 pieces. Problem is, you don't get to pick which two, and which two could change. Does that make you feel comfortable about this anchor design?
In reply to:
2 smart guy's didn't analyze how the equalette "spanks" the sliding-X; they performed a carefully controlled experiment that reportedly resulted in showing the improvement over the sliding X
What they analyzed is not what is shown in the drawing. They analyzed 2-placement anchors.
In reply to:
the likely problem with the sliding X ("clutching") is not the same things as friction of cord sliding around a biner
The likely problem with the sliding X is that when the master point carabiner slips on the cords to allow equalization, the cords are running next to each other in opposite directions; they might even overlap each other. This effect would probably be worse with webbing than with cord. The equalette also has more friction than you'd expect, because the two carabiners pinch the cords. What's "clutching"?

Did you notice that fingertrouble posted an illustration from his mountaineering book in the "Solution to.." thread? He asked if the design was a 1-carabiner equalette. It looks like the answer is "Yes" in the sense that John Long uses the term "equalette" to refer to a 2-placement anchor. It also looks like fingertrouble's design would have less than half the sliding friction at the power point of an equalette, but it wouldn't have the redundancy benefit of two identical lockers (they must be identical and the cord lengths between the limiter knots must also be identical) at the power point. It also looks like you could keep the benefit of lower sliding friction than the equalette (and sliding X) while gaining the equalette's redundancy by adding a carabiner (any carabiner) between the unclipped (not required to be identical length) strand between the limiter knots and the power point locker of fingertrouble's design. So it looks like the equalette (however you define it) has room for improvement, without adding any extra parts, in fact with backing off on some of the requirements.

Looks like fingertrouble is trying to be helpful, in his own special way :roll: . Cut him some slack. :wink:


billl7


Mar 15, 2006, 4:12 AM
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Re: Improved sliding x: Is it really safer? [In reply to]
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In reply to:
But the equalette (and quad) seems to be the only new trick in the bag that I will actually start using with any regularity.
Likely, it's right under my nose but I can't find a good pic or description of the quad - searched from page 26 onward. Is it basically a sling with limiter knots and a couple biners on each of the inner 2 strands? Or if someone can kindly shove me in the right direction I'd appreciate it.

Bill L.


healyje


Mar 15, 2006, 4:20 AM
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mhabicht,

Just wanted to say that the more I play with your rig (michalette?) the more I like it. I don't necessarily like the interplay of knot and biner but my cord is too short to tie an "in-line figure-8" which is what should be used. Good on you for thinking it up - this is one I might actually use if I wanted more active equalization than a straight equalette. Here is my shot of it:

http://www.cascadeclimbers.com/...0/6299michaelrig.jpg


papounet,

The principal problem I have with your variant of this design is you've removed the cloves which I think are actually the key element of mhabicht's design and one it shares with the equalette. It equalizes more than adequately with the cloves and suffers far less extension with them than without them. I think your use of rings is fine, but I think you downgrade the one of the best aspects of the design removing the cloves.


billl7


Mar 15, 2006, 4:34 AM
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In reply to:
Looks like fingertrouble is trying to be helpful, in his own special way :roll: . Cut him some slack. :wink:
If you had been very convincing in your responses to my points/questions then I'd consider giving him some slack. :wink:

Bill L.


moose_droppings


Mar 15, 2006, 4:51 AM
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Hugepedro
Couldn't you use 3 sliding X's in thats place like pictured on page 9?
Looks to be close to the same thing, either way is pretty simple.
The same would go for the 3 sliding X's on a 3 arm anchor, middle leg would get 50%. If one felt the need for 4 pieces I would be inclined to use this if the situation warranted it.

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