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paulraphael
May 17, 2007, 3:47 PM
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I know, not another one of these.
Bear with me. I've been developing a method that I like more than any of the other current proposals, including the equalette. My partner and I have begun field testing it at the Gunks, and so far find it faster and simpler than other setups we've used. It does an excellent job equalizing three pieces.
This is not a revolutionary departure; it's a simplification and refinement of familiar ideas.
A description with pictures, discussion, and questions can be downloaded here:http://www.paulraphaelson.com/downloads/acr.pdf.
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trenchdigger
May 17, 2007, 3:57 PM
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This is identical in function to the Trango Alpine Equalizer. The system lacks redundancy at the master point (outside of attaching the rope to an additional piece). You also do not want to clip multiple carabiners to the rap ring power point. Loading multiple carabiners in the power point will abnormally load the power point.
There is also a way to tie something very similar to this out of a cordelette and have a standard tiedcordelette style master point which should be better/safer to clip than a rap ring. If I can find a picture, I'll post.
Good work though... keep thinking.
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paulraphael
May 17, 2007, 4:13 PM
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trenchdigger wrote: This is identical in function to the Trango Alpine Equalizer.
Yes, but it requires no specialized gear, weighs less, costs less, and can be used in many different ways.
In reply to: The system lacks redundancy at the master point (outside of attaching the rope to an additional piece).
Yes, this is discussed at length in the document. In most cases I consider it a tradeoff and not a deal breaker.
In reply to: You also do not want to clip multiple carabiners to the rap ring power point. Loading multiple carabiners in the power point will abnormally load the power point.
Not in any way that I've found. The ring is symetrical and has no weak axis. It also loads the carabiner closer to its strong point (next to the spine) than a multiistrand cordelette. Maybe I don't understand what you're getting at.
In reply to: There is also a way to tie something very similar to this out of a cordelette and have a standard tiedcordelette style master point which should be better/safer to clip than a rap ring.
I've seen a number of these proposed. Some offer more levels of redundancy, but all are slower, more complex, and offer more oportunities for tying incorrectly. I haven't been able to find any case against the ring as a safety liability.
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binrat
May 17, 2007, 4:35 PM
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WHAT Another one??..............just joking. Looks easy to set up but have you tried to shock load it yet?
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paulraphael
May 17, 2007, 4:43 PM
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binrat wrote: WHAT Another one??..............just joking. Looks easy to set up but have you tried to shock load it yet?
Yeah, I know ... yet another one. We're hoping to gather enough interest so that someone volunteers to perform a drop test with load cells. My partner says I don't pay him enough to take a voluntary f2 fall.
The questions I'd like to resolve with a test are:
1) how efficiently does it distribute the load ... which is pretty academic because I'm sure it does a good enough job. but people might want to know.
2) how much cord strength is lost with the various adjusting knots. This question strikes me as the important one. I especially want to see results with a slopily tied knot, because it's inconvenient to thoroughly dress an overhand on a loop tied in two strands.
For my working calculations I've been assuming a loss of 50% strength (a very weak knot), but it's not wise to assume anything with knots.
3) what are the real world peak forces possible with extensions of 6 inches, 12 inches, 18 inches, etc.. Largo's book touches on this, but it would cool to see tests that include a real belayer.
(This post was edited by paulraphael on May 17, 2007, 5:00 PM)
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trenchdigger
May 17, 2007, 5:20 PM
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paulraphael wrote: trenchdigger wrote: This is identical in function to the Trango Alpine Equalizer. Yes, but it requires no specialized gear, weighs less, costs less, and can be used in many different ways.
I'll give you three of the four, but the Alpine Equalizer definitely weighs less 
paulraphael wrote: trenchdigger wrote: The system lacks redundancy at the master point (outside of attaching the rope to an additional piece). Yes, this is discussed at length in the document. In most cases I consider it a tradeoff and not a deal breaker.
To me it is. I feel that a majority of the time, redundancy is far more important than equalization, and I feel that redundancy at a single point is optimal. I'd prefer not to autoblock belay my partner off a non-redundant master point.
paulraphael wrote: trenchdigger wrote: You also do not want to clip multiple carabiners to the rap ring power point. Loading multiple carabiners in the power point will abnormally load the power point. Not in any way that I've found. The ring is symetrical and has no weak axis. It also loads the carabiner closer to its strong point (next to the spine) than a multiistrand cordelette. Maybe I don't understand what you're getting at.
Loading multiple carabiners at once in a ring like that will put an outward force on the ring and could even theoretically magnify the loads in the right situation (similarly to the way making the angle between cordelette arms too obtuse magnifies loads). Picture three carabiners clipped to the rap ring. Now load the outer two. Not only are they pulling down on the ring, but also pushing outward. Hope that makes the point clear. I don't think it's especially dangerous, but it has potential for unusual loading. I think using a large locking carabiner (like the DMM Boa) might be better in place of the omega ring.
paulraphael wrote: trenchdigger wrote: There is also a way to tie something very similar to this out of a cordelette and have a standard tiedcordelette style master point which should be better/safer to clip than a rap ring. I've seen a number of these proposed. Some offer more levels of redundancy, but all are slower, more complex, and offer more oportunities for tying incorrectly. I haven't been able to find any case against the ring as a safety liability.
The one I'm thinking of offers no redundancy (unless you tie limiter knots or clove hitch a piece) but is tied similarly. You can easily use a ring/rings for the sliding point(s) and still have a soft master point. I'm still looking for that photo....
You can also achieve something very similar using the rope. Clove hitch a single piece, run the rope through the biner on a second piece, and clove hitch a third piece. Pull the loops down between the outer pieces and the inner piece and clip them as your master point. The drawback comes when you're not swinging leads or need that extra 10' of rope to reach the next belay. Also, that system only gives you 25/25/50 equalization.
(This post was edited by trenchdigger on May 17, 2007, 5:44 PM)
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binrat
May 17, 2007, 5:20 PM
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Paul;
have you ever seen this knot?
http://www.sarbc.org/sarbc/knot1.html
I've used it with webbing and it worked well, but I would not really quess on redundancy of it.
Binrat
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trenchdigger
May 17, 2007, 5:24 PM
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binrat wrote: Paul; have you ever seen this knot? http://www.sarbc.org/sarbc/knot1.html I've used it with webbing and it worked well, but I would not really quess on redundancy of it. Binrat
That's very similar to the system I'm thinking of. Just a different knot. The one I've seen uses an eight on a double bight in a cordellete that's already tied into a loop. Likewise, the 2 lockers in this system could be replaced with rap rings.
The system is not redundant. Cut the cord and you're done. It does, however, equalize 2, 3, or more (just add more arms/biners) pieces very well. As Paul points out, some level of redundancy can be added by clipping the rope to one of the pieces in the anchor.
(This post was edited by trenchdigger on May 17, 2007, 5:42 PM)
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paulraphael
May 17, 2007, 5:43 PM
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trenchdigger wrote: I feel that a majority of the time, redundancy is far more important than equalization, and I feel that redundancy at a single point is optimal. I'd prefer not to autoblock belay my partner off a non-redundant master point.
I think redundancy needs to be looked at in context. Most people are satisfied with a single rope and a single harness, because the faiure rates of these items are so low. So the question is, what is the likelihood of failure of a loop of 7mm nylon cord?
Keep in mind also that the cord (and tie-in, and locking biner) are backed up on the strongest piece of pro. So the system IS redundant. It simply doesn't offer as many layers of redundancy as some other methods. Whether it offers enough redundancy or not is a question that is situation-specific.
I personally would not use this by itself as a toprope anchor, because that's a situation where the rope backup is unavailable, and where there's no one standing there who can notice if the cord flops over a sharp edge, or gets damaged by rockfall, or whatever.
trenchdigger wrote: Loading multiple carabiners at once in a ring like that will put an outward force on the ring and could even theoretically magnify the loads in the right situation (similarly to the way making the angle between cordelette arms too obtuse magnifies loads). I don't believe this is so. A ring has no weak axis. multiple outward (or inward) axial loads actually take advantage of a ring's strength better than the kind of inline load used to test a rap ring. Think of a bicycle rim. In a wheel it sustains 3000 to 5000 lbs of tension from the spokes, distributed radially. But if you remove all but two opposing spokes the rim will distort. the distributed load actually strengthens the structure of the rim. This is academic, but it's an illustration of how you're not going to hurt a ring by loading in multiple directions. Tthere's no correlation between multiple biners on a ring and load multiplication with slings. The ring is safer in virtually every way than a locking biner. paulraphael wrote: trenchdigger wrote: There is also a way to tie something very similar to this out of a cordelette and have a standard tiedcordelette style master point which should be better/safer to clip than a rap ring. I've seen a number of these proposed. Some offer more levels of redundancy, but all are slower, more complex, and offer more oportunities for tying incorrectly. I haven't been able to find any case against the ring as a safety liability. trenchdigger wrote: You can also achieve something very similar using the rope. Clove hitch a single piece, run the rope through the biner on a second piece, and clove hitch a third piece. Pull the loops down between the outer pieces and the inner piece and clip them as your master point. The drawback comes when you're not swinging leads or need that extra 10' of rope to reach the next belay. Yeah, there are a lot of workable direct tie-in methods. And a lot of times when you won't want to tie in directly. I'm addressing the times when you want an independent anchor.
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trenchdigger
May 17, 2007, 6:32 PM
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paulraphael wrote: I think redundancy needs to be looked at in context. Most people are satisfied with a single rope and a single harness, because the faiure rates of these items are so low. So the question is, what is the likelihood of failure of a loop of 7mm nylon cord?
paulraphael wrote: There's no correlation between multiple biners on a ring and load multiplication with slings. The ring is safer in virtually every way than a locking biner.
The blue ring represents the OP rap ring. The red circles represent carabiner cross sections clipped to the ring. If the carabiners end up in an orientation where the angle theta is greater than 60 degrees, load multiplication occurs - just like when you exceed 120 degrees between arms in a multi-point anchor.
paulraphael wrote: I've seen a number of these proposed. Some offer more levels of redundancy, but all are slower, more complex, and offer more oportunities for tying incorrectly.
(This post was edited by trenchdigger on May 17, 2007, 6:32 PM)
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paulraphael
May 17, 2007, 6:49 PM
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I see what you're getting at with that diagram, but I have to ask if you're really serious ... ? Under what circumstances are three people going to land on the powerpoint of an anchor in a way that could produce anywhere near 20kn of load (even if they managed to arrange themselves in series so the load was dead parallel as in your diagram). Also keep in mind that the ring only sustains 2/3 of the load in this anchor configuration.
I still think a carabiner would be weaker and less secure in every imaginable way. Keep in mind that a biner's strength plumets when the load moves even a centimeter from its strong axis (represented by the indentations next to the spine, made by the 5mm steel pins of the testing aparatus).
There are a lot of things worth picking apart in an anchor rigging; I really don't think this is one of them (but if the ring keeps you up at night, you could always use 30kn or 50kn stainless ring).
(This post was edited by paulraphael on May 17, 2007, 6:51 PM)
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knudenoggin
May 17, 2007, 7:08 PM
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I'm not buying this load-multiplication bit re the rap ring: it will load the ring
in an unusual way in terms of points of contact and hence where the force
to bend is concentrated, but the ring itself has a given geometry for holding
the load. (And maybe 3 opposed to 3 'biners within it would prove stronger
than 1 vs 1, which will see the roundness head towards ovalness.)
The angle of the ring vis-a-vis each side 'biner is less perpendicular to the
axis of loading than for the center 'biner, afterall.
*knudeNoggin*
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trenchdigger
May 17, 2007, 7:09 PM
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paulraphael wrote: I see what you're getting at with that diagram, but I have to ask if you're really serious ... ? Under what circumstances are three people going to land on the powerpoint of an anchor in a way that could produce anywhere near 20kn of load (even if they managed to arrange themselves in series so the load was dead parallel as in your diagram). Also keep in mind that the ring only sustains 2/3 of the load in this anchor configuration.
trenchdigger wrote: ... [carabiners clipped to the rap ring master point] could even theoretically magnify the loads in the right situation... I don't think it's especially dangerous, but it has potential for unusual loading.
paulraphael wrote: There are a lot of things worth picking apart in an anchor rigging; I really don't think this is one of them (but if the ring keeps you up at night, you could always use 30kn or 50kn stainless ring).
Still, I'm going to be pissed if you bring me up on autoblock clipped to any non-redundant master point.
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chrisb
May 19, 2007, 3:04 AM
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In the interest of full disclosure, I'm Paul's partner, but the design is totally his.
I know this is blasphemy, but the issue of redundancy (wrt the single strand of cord) seems vastly overblown to me:
How many folks use a single sling to extend a rap device? No redundancy there (unless your friction backup goes through the belay loop). How about using a single locker for our belay/rappel set up--there seems to be a MUCH greater chance of failure (cross loading/shock loading gate) and plain old user error (unlocked/rope twists out). And yet these are conventions no one seems to question.
Additionally, anyone who's climbed beyond a crag knows that protection and anchors are inevitably situational. Sometimes a slung horn is all you need (and all you get); other times we're making deals with God for just one good piece. And in those situations where we pray our second doesn't fall, wouldn't you rather have your pieces as well-equalized as possible (which the ACR does a damn good job of accomplishing) instead of knowing that catastrophic rockfall is marginally less likely to cut your cord? Let's be serious: if rock chops out your anchor, you're probably next in line.
In the mountains, efficiency and speed are the order of the day and this rig lends itself especially well to those demands (while also allowing for use as a traditional cordalette/equalette).
There will never be one right/best thing to use every time: we apply the tools and techniques to the situations as we encounter them. And I feel that Paul's rig is highly applicable in a variety of situations.
By the way, has anyone even tried this out? Where are all the Lab geniuses? I'm kind of disappointed...
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ja1484
May 19, 2007, 4:12 AM
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paulraphael wrote: I still think a carabiner would be weaker and less secure in every imaginable way. Keep in mind that a biner's strength plumets when the load moves even a centimeter from its strong axis (represented by the indentations next to the spine, made by the 5mm steel pins of the testing aparatus).
I need to address a lot of things in this post.
The anchor rigging seems easy to set up. Other than that, I don't see any advantages. Maybe slightly better equalization than an equallette, but I'm not sure we need more, given real world forces in climbing falls.
Next is that damned OP rap ring. You better get a steel ring on there if you really want security. OP aluminum rap rings are made from the same barstock as their carabiners and weaken in the same fashion. They are meant to be loaded along one axis only. This rigging offers a minimum of tri-axial loading when weighted (downward on the power point, and at least 2+ arms.)
Michael Lane, employee of Omega Pacific, has this to say about OP rap rings in anhors:
In reply to: First, speaking as an official Omega person, I confirm that the the rap rings are designed to be used as rappel rings. Anything other than that is outside the parameters of design and I can't say that they're appropriate for anything else until a bunch of pointy-headed engineers and designers around here sit down to talk about it for a long time. The rap rings are tested like our 'biners. That is, they're put in a load cell with CE-compliant fixtures and loaded to failure. Three-sigma applies and 20kN is the rated strength. They are built with similar material to our biners e.g. 7000-series aluminum and the barstock is 11mm, pretty much the same as our standard Oval 'biner. Therefore, when it comes to wear and repeated lowering (meaning ropes running over the aluminum), you can expect it to wear and behave much like our oval would. Likewise, when using our Rap Rings, one must be careful not to apply simultaneous, multi-directional loading. In other words, put the load along one single axis. To load them otherwise is to weaken them. Just like a carabiner.
Source post is here:
http://www.rockclimbing.com/...post=1577456#1577456
All in all, I say stay with the equallette - it's KISS, and it doesn't try any fancy jiggery-pokery with integrated rap rings to attempt to achieve greater equalization in *some* situations at the sacrifice of redundancy.
I respect people trying to constantly develop better anchor systems, but I think we've reached a point in climbing gear technology where we don't really need to advance any further. Injuries and deaths from gear failure are very uncommon and usually result from neglect on the part of the gear owner regarding retiring them on time or using them properly.
A good shot, but it seems to have many kinks to work out yet.
(This post was edited by ja1484 on May 19, 2007, 4:13 AM)
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paulraphael
May 19, 2007, 2:49 PM
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If you're really worried about that ring, you could substitute a 30kn steel ring and be done with it. Personally, looking at the physics of the ring, and how it's used in this setup, I'd bet anyone a thousand dollars that the locking biner would fail in a drop test first.
As far as KISS, all I can suggest is try it. The people who have actually used this setup find it faster and easier to rig in a variety of settings than anything else they've used. The equalette is a simple concept, but tieing it and dressing it in real world situations takes more time and care than this setup. Which was the reason for its inception.
Seriously, you can test the concept in your living room with a cordelette and locking biner and fifteen minutes of your time. Once you figure out the way the limiting knots behave, you can tie together any 3 piece anchor in under thirty seconds.
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vivalargo
May 19, 2007, 4:03 PM
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I think there's about four or five (more??) viable alternatives or variations on the original Equalette, and the thing to do is test them all and see what's what in terms of performance.
First thing is to build a list of the alternatives or new rigging systems that folks think are basic and straighforward enough to some day catch on.
Next thing is to find an outfit to so the drop testing. They guys at Sterling are the best but I can't ask them to do this kind of work again for nothing. It literally takes hundreds of hours.
That means someone's gonna have to hustle up a grant, possibly from the AAC. No one wants to payt for anything along these lines so I can't imagine this is going to be an easy task.
JL
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rgold
May 19, 2007, 7:13 PM
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paulraphael wrote: Questions...how efficiently does it distribute the load ... which is pretty academic because I'm sure it does a good enough job. but people might want to know.
Beware of the obvious. "Academic" analyses suggest poor equalization because of friction, and such pull-testing as has been done also suggests the friction in pulley systems could result in unacceptably poor equalization. For example, Craig Connolly says he has pull-tested an Alpine Equalizer and found, in one case, only 6% of the power-point load on one of the arms.
On the other hand, my Geekqualizer has been subjected to drop tests with the outer pair of arms at a 90 degree angle and one of those arms cut 90% through. A drop-test impact at the power point of 11.4 kN did not result in the failure of the rig. Was that outer arm analogous to the one that, in Connolly's test, got only 6% of the load, or did the rig equalize and so keep the load on the cut arm under 4kN? We don't know...
It isn't clear whether the results of pull-testing correspond to the results of drop-testing when friction in a pulley system is a factor. Wootles drop-tests suggesting better equalization for the sliding X over a cordelette are contrasted with some pull tests (I don't have the reference at present) that reached the opposite conclusion.
The Geekqualizer is built on an AE and so has similar potential friction problems (not as bad as PR's system, which will suffer from occurrences of the binding effect already observed for the sliding X in drop-testing). The severity of frictional effects won't be clarified until, as Largo says, we get a bunch of drop tests. Until then, there is the possibility that pulley systems, in spite of their hypothetical advantage in the absence of friction, could in reality be no better and perhaps worse than a cordelette when it comes to real-life equalization.
Edit: The issue of money for testing is, of course, critical. The AAC seems to me to be the only likely source. I have written Phil Powers twice to advocate for an AAC role in this kind of testing. His replies have been receptive, but of course I'm just a single voice. I would suggest that everyone who thinks it is important to understand anchor loads and rigging methods do two things: (1) join the AAC if you haven't, and (2) inundate the president with requests for a testing program.
(This post was edited by rgold on May 19, 2007, 7:21 PM)
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paulraphael
May 19, 2007, 7:59 PM
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rgold wrote: The Geekqualizer is built on an AE and so has similar potential friction problems (not as bad as PR's system, which will suffer from occurrences of the binding effect already observed for the sliding X in drop-testing)
It's possible (and I'd like to see tests) but there are a couple of significant differences between between this setup and a sliding X. For one, the strand connecting the outer anchors is separated from the the center strands, so it can't bind over them. For another, it uses cord and not webbing; webbing has shown itself to be more likely to run over itself and bind than cord.
I'd be curious to know what circumstances led to the AE distributing only 6% of the load to one of the arms. Did they elaborate?
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rgold
May 20, 2007, 3:52 AM
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"paulraphael wrote: It's possible (and I'd like to see tests) but there are a couple of significant differences between between this setup and a sliding X. For one, the strand connecting the outer anchors is separated from the the center strands, so it can't bind over them. For another, it uses cord and not webbing; webbing has shown itself to be more likely to run over itself and bind than cord.
I think the test of any equalizing system is for three pieces in a vertical line, partially because the friction will be highest in this case, and also because cordelettes are at their worst in this configuration. In the vertically aligned case, the strands in PR's rig are not separated; all are together and parallel. If they don't cross and bind, they'll certainly be rubbing against each other.
paulraphael wrote: I'd be curious to know what circumstances led to the AE distributing only 6% of the load to one of the arms. Did they elaborate?
As far as I know, no.
(This post was edited by rgold on May 20, 2007, 4:03 AM)
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paulraphael
May 20, 2007, 7:00 AM
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Good point about the vertical orientation; I haven't had an opportunity to use it like this in the field. I'll set it up and see if there are any obvious issues.
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paulraphael
May 20, 2007, 4:16 PM
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I tried a couple of different vertical configurations to see if there would be any issues. With angles approaching zero degrees, the movement of the strands when load angle changes is minimal. There's only a lot of motion if the anchor is pulled off axis by 30 degrees or more (as in a big pendulum fall). Friction of the strands over each other was minimal.
I tried putting a deliberate twist in the middle strand to see if this would cause binding. One out of the three times i dropped a weight onto the anchor (off axis, in a pendulum type fall) the strands bound, causing the load to be distributed to only two of the arms. I couldn't get this to happen when the anchor was set up properly (no twists).
So this is something to look out for, especially when the arms are parallel or nearly so.
The other issue in a vertical crack is extension. In the example in the attached picture, if the top or bottom piece were to blow, the extension would be under thee inches (the bottom piece is close to the power point, the top piece is tied off with a limiter knot). If the middle piece blows, extension will be 8-1/2 inches. I'd be ok with this, but if your placements were such that the lower piece and the middle piece were more than a couple of feet apart, you'd want to bring the arm lengths closer together by using different length runners.
(This post was edited by paulraphael on May 20, 2007, 4:17 PM)
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knudenoggin
May 20, 2007, 5:57 PM
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In reply to: Therefore, when it comes to wear and repeated lowering (meaning ropes running over the aluminum), you can expect it to wear and behave much like our oval would.
can be rotated to distribute repeated loadings in different places (though I have
seen some thin rings that became a bit oval, and hence held a particular position).
In reply to: Likewise, when using our Rap Rings, one must be careful not to apply simultaneous, multi-directional loading. In other words, put the load along one single axis. To load them otherwise is to weaken them. Just like a carabiner.
of triaxial loading?
In the particular case at hand, I'd think that any weakening would be slight,
and beyond concern for the range of conceivable loads.
*kN*
ps: "Wootles drop-tests suggesting..." --huh? RGold, you're suffering forums daze:
no "Wootles" here, though there is a poster of sterling qualifications as a tester!
(This post was edited by knudenoggin on May 20, 2007, 6:12 PM)
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rgold
May 20, 2007, 5:59 PM
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PR's picture illustrates the equalization challenges faced by all rigging systems. The arm-length ratio in the picture is roughly 7:4:1. If rigged with a a fixed-arm method such as a cordelette, the powerpoint load will also be distributed so that the long arm gets 4/39 ~ 10% of the load, the middle arm gets 7/39 ~ 18% of the load, and the short arm gets the remaining 72% of the load.
These distributions occur because the absolute stretch in each arm is the same (= the distance the powerpoint moves down), but the relative stretch, which determines arm tension, is significantly different because the arm lengths are significantly different.
In pulley-type systems, the ability of the strands to run around the pulleys accomodates differential lengthening and stretching. If the pulley is frictionless, then strand tension on either side of it will be equalized. But if the pulley has friction, and some computations suggest carabiners supply a frictional force equal to 1/3 the load, then the setup will stabilize with unequal strand tensions on either side of the pulley. The rig pictured in PR's attachment has six pulley points. The dynamics seem complicated, but if the tensions on either side of these pulleys could differ by a factor of 1/3, the cumulative effect could be very substantial differences in arm tension, enough, perhaps, to produce Craig Connoly's observation referred to previously.
Of course, the rig must be set up in a way that will permit the pulley rope to run. You don't want a knot to run into a ring or carabiner before a long strand has had the chance to elongate properly. This illustrates another worry about these systems; their complexity means that they may not work as expected because of some overlooked obstacle to performance.
I think the best hope for pulley systems is that the frictional effects are not so great under high-impact "shock" loading, something which can only be decided by those tests we keep wishing would be magically funded.
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ja1484
May 20, 2007, 6:44 PM
Post #25 of 53
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Registered: Aug 11, 2006
Posts: 1935
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knudenoggin wrote: In reply to: Therefore, when it comes to wear and repeated lowering (meaning ropes running over the aluminum), you can expect it to wear and behave much like our oval would. This makes little sense: UNlike an oval 'biner, a ring has no set axis and thus can be rotated to distribute repeated loadings in different places (though I have seen some thin rings that became a bit oval, and hence held a particular position). In reply to: Likewise, when using our Rap Rings, one must be careful not to apply simultaneous, multi-directional loading. In other words, put the load along one single axis. To load them otherwise is to weaken them. Just like a carabiner. Likewise, I remain unconvinced by this argument. Has anyone actually tested some sort of triaxial loading? In the particular case at hand, I'd think that any weakening would be slight, and beyond concern for the range of conceivable loads. *kN*
Did you actually read the source on those quotes you're arguing against?
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