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Neoshade


Aug 17, 2011, 3:12 PM
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Stupid Simple Elette
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OK, please don't hate, this is one of my first posts, and I KNOW that everyone is sick of equalette and other invented anchor discussions, especially from those who haven't read every single comment and thread so far, and John Long is probably getting death threats from trolls and old-school climbers alike. However, I gotta throw out another one. (assuming it hasn't been done already)

One more caveat - I really love that the discussion that's been going on, and I truly believe that better anchor designs are forthcoming, and that awareness and discussion and testing are a GOOD thing, despite the massive amount of overdesign and confusion (this stuff is for mostly trad and alpine anchors that need equalization for safety.

So, as many people have noted, a more complex anchor is less effective because it's difficult to make, has greater possibility for mistakes, and in the environments of alpinism and big walls, wasting time means losing daylight, freezing your partners, and then hurrying, which is far more dangerous than most fractional amounts of equalization and load sharing. I'll be the first one to admit that I've thrown a single 11mm sling over a rock horn and yelled "On Belay!" because we were way off course on a knife edge at 12,000' and it was getting dark.

So, aside from the dogged chase for SRENE perfection, a useful anchor should use standard climbing gear, rig quickly, and be simple enough for brief visual inspection.
I also second the need for a single master-point biner in all real word use. (double equalette biners are great for setting TR anchors with pro at your weekend crag, but impractical for trad climbing)
On that note, I tend to ignore the 2-biner redundancy for equalettes, and just sliding-x the thing. I just don't care that much about friction binding on the X. It's so much better than the cordalette, when dynamic equalization is needed, let's not split hairs.

On the subject of equalization - I don't know how John Long's tests were conducted for off-axis loading, but from what I've noticed in the Real World, the rope is pulled and wiggled in the direction of a fall while climbing before a fall takes place. So, if the anchor is pulled in the direction of the impending fall ahead of time, as the climber moves around, then it's pre-equalized in that direction already, and any friction binding of the X is not a concern.

Lastly, I love the 2 leg equalette, It's my new go-to for sport routes with anchor bolts in weird places (not side-by-side) and it's stupid simple to tie, keep tied, and it works. It's really just a sliding X with limiter knots if you're only using 2 legs and a single MP biner instead of 2.
Lots of the variations on this so far are really great, like the tripplette, clove-hitching the pro on a sliding W, and Paul Raphaelson's and others' methods of just throwing a sling or climbing rope clove on additional pro (3rd or 4th piece) and leave the primary rig alone.

My rigging solution is a very simple adaption to the equalette or almost any of these ideas.
The limiter-knotted sliding X, or with double MP biners, the equalette is great with 2 legs, but has trouble maintaining simplicity and equalization with 3 or 4 pieces. And if it's not equalizing, or it's hard to get tied right, then screw that; you might as well use a cordalette or any other simple, classic method (ie: climbing rope cloves with a MP knot).

So, as others have mentioned using knots other than a clove hitches to each piece to get an equalette leg unto multiple pieces of pro, how about Ultrabiker's figure 8?

The knot is a double figure 8 on a bight, with Ultrabiker's modification being to use each of the three loops created as legs of an anchor.
It's an amazing knot for adjusting legs, as one strand from each leg slip-knots through the knot to the next leg, so that it can self-equalize as long as it's not loaded, just by pulling the 8 around.
However, as an anchor rig itself, it's not at ALL redundant for cuts, it can possibly extend if the rope slips through the knot, and the MP itself lacks stout redundancy in having all single strands and only 1 knot to rely on for the whole rig.

BUT - this knot is perfect for a secondary anchor on a cordallete or equalette.
Each lef of a Double-Figure-8-on-a-bight can self-equalize, and the whole thing can be adjusted for length pretty darn easy.

My preference is to find a good anchor for 2 or 3 peices, whatever works for my situation, and then just throw extra slings or draws at additional pro as needed to extend legs, or make a meta-rig (if there's a better term, illuminate me :P) to eqaulize two pieces before connecting them to a single leg.
basically, tie a 2-leg equalette, or 3 leg cordalette, and then throw a little sliding-X on any extra pieces and clip them to a leg.
This not only keeps the anchor simple, uses gear you've got on you, and keeps the SRENE properties of the primary rig, but allows far greater equalization and customization for the circumstances.
Don't make your primary rig too complex. Just fix your pro as needed and use a simple anchor.

So, the culmination of all this blab (really, I could have just used quotes from all over these forums, I know) is that there is a way to take the simple 2-leg limiter-knotted Sliding X or an Equalette, and add additional pro at no further cost to you or your tired brain!

1) Make yourself your favorite 2-peice anchor rig with some 20' cordalette or whatever, use those limiter knots and slings to extend pro as you feel necessary.

2) Take a leg that needs to be split among 2 pieces of pro, and tie a Double-Figure 8 on a bight (a 2 second knot with your eyes closed) and clip the loops of the double 8 to the pro.

3) Congrats! You've now got a meta-rig that will self-equalize with just a bit of wiggling until it's loaded, and can be adjusted with a simple squeeze-push-fiddle-pull at any time thereafter, easier than a clove.

http://www.flickr.com/...2896@N00/6054296344/







Pros:
- It won't mess with your primary rig and its SRENE properties.
- It will self-equalize between the peices before loading, while using only a knot in the 7mm perlon (or whatever)
- It will slip a little under load, further equalizing, not perfectly, but darn well.
- Any extension to do failure of pro is small and not worth caring about, because the knot doesn't slip much, and cause it's a little meta-rig, not your whole anchor.
- The whole darn thigs ties and equalizes in a few seconds.

Cons:
- Doesn't self-equalize perfectly. Needs Wiggling.
This is for real world stuff, where we're either at the belay to give it a shove as needed, and where the climbing is being actually belayed, with the rope tugging the anchor around enough to get it equalized-ish. That's all we're looking for. Load distribution among pieces of pro, not laboratory pefect equalization. Also, this knot allows some slippage, enough to provide the distribution of force we need.
- Shortens up one side of an equalette, so now your limiter knots aren't in the middle!
Oh no! Just go tie another knot on the other leg. Use up some rope. Like a fig8 perhaps? That should about even it out. :P Otherwise, this is a common problem with the equalette, not so much my knot application.
- I'll wait for you guys to fill in the rest :)


Lasty, let's not name anything else with a "lette", shall we? Neoshade's Rig, whatever. And if this has been done by someone else, and completely debunked, feel free to trash on me all you want. I'd deserve it.


patto


Aug 17, 2011, 3:40 PM
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Re: [Neoshade] Stupid Simple Elette [In reply to]
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Nothing is wrong with a simple cordalette setup. Or even better use the damn climbing rope.


Stormeh


Aug 17, 2011, 4:59 PM
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Re: [Neoshade] Stupid Simple Elette [In reply to]
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Your pictures are very pretty. Also, seems like a good setup. I'd use it in place of the equalette but I'm not exactly sure what the advantages are using the double fig 8 over just cloving one strand of the leg to each piece as in the classic equalette.


mbrd


Aug 17, 2011, 5:49 PM
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Re: [Neoshade] Stupid Simple Elette [In reply to]
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c'mon, "neoshadelette"? doesn't that sound swell?

(gotta edit this- i wasn't referring to you as "neoshadelette")


(This post was edited by mbrd on Aug 17, 2011, 5:51 PM)


Neoshade


Aug 17, 2011, 9:17 PM
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Re: [patto] Stupid Simple Elette [In reply to]
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Dear Patto,
I love cordalettes, I've been using them for years, but we now know that a cordalette doesn't equalize for shi* when loaded off-center. Even just a inch or two off center. So while it's all well & good for most climbs and TR anchors, it is in great need of a replacement for trad traverses and crappy pro that needs a decent distribution of the load.
If you don't care, use the cordalette for everything. You probably won't die, and will more likely never climb anything sketchy enough to need equalization. Good for you.
No one's telling you what anchor to use, this is The Lab, and we're discussing theory.
Dont' troll.


(This post was edited by Neoshade on Aug 17, 2011, 9:18 PM)


Neoshade


Aug 17, 2011, 9:28 PM
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Re: [Stormeh] Stupid Simple Elette [In reply to]
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In reply to:
"Stormeh"...I'd use it in place of the equalette but I'm not exactly sure what the advantages are using the double fig 8 over just cloving one strand of the leg to each piece as in the classic equalette.


I haven't had a chance to take any whippers on it yet, and will post back when I do, but let me know if you or anyone wants to give it a go. I really want to see how well it equalizes the arm parts under a fall.
And that is also the answer to your question - it beats cloves because it equalizes the 2 pieces on the arm of the equalette (or whatever you're tying). Cloves don't do this at all: If you swing the MP around, only one of the two pieces of pro is getting the load of the whole arm.
Cloves are great, but the idea is that this is just as fast, equalizes much better, and even easier to adjust.
Tie it (if you know the double 8) and yank it around. It self-adjusts most of the way with a loose knot, and will equalize further under load. It's pretty sweet.


Neoshade


Aug 17, 2011, 9:32 PM
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Re: [Neoshade] Stupid Simple Elette [In reply to]
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*Note
The Pros and Cons I mention near the end of my post, referring to "the knot" - I'm just talking about the use of a double-8 on the leg(s) of an Equalette, Sliding X or similar anchor for additional pieces of pro.


potreroed


Aug 17, 2011, 9:32 PM
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Re: [Neoshade] Stupid Simple Elette [In reply to]
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I've been climbing for 45 years and have never used a 'lette of any type. Why complicate things? I'm with patto on this one. Use the rope and the PAS which you'll have already girth-hitched on your harness if you're smart.


mbrd


Aug 17, 2011, 9:39 PM
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really? no room for equalizing marginal placements to protect shady spots?

guess i'll never be a hardman...


patto


Aug 17, 2011, 11:58 PM
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Re: [Neoshade] Stupid Simple Elette [In reply to]
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Neoshade wrote:
No one's telling you what anchor to use, this is The Lab, and we're discussing theory.

We if we are going to discuss theory could you please explain how the above device equalises dynamically? Furthermore lets discuss how no extension and dynamic equalisation are mutually exclusive. Finally how about we discuss how extension in a typical scenario results in shock loading the anchor and can result significantly higher forces.


Neoshade


Aug 18, 2011, 1:28 AM
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Re: [patto] Stupid Simple Elette [In reply to]
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patto wrote:
Neoshade wrote:
No one's telling you what anchor to use, this is The Lab, and we're discussing theory.

We if we are going to discuss theory could you please explain how the above device equalises dynamically? Furthermore lets discuss how no extension and dynamic equalisation are mutually exclusive. Finally how about we discuss how extension in a typical scenario results in shock loading the anchor and can result significantly higher forces.

I don't want to get to far into it, Really, much of all that has been discussed over and over elsewhere in these forums.
But basically, the Doudle Figure 8 will allow rope to slide from one loop to another a bit until the knot is loaded. That's what I mean by dynamic equalization - it equalizes on the fly as the rope moves. I'll look more into other discussions of the knot, most importantly how much slippage and equalization takes place under a fall load. Sorry, can't say yet. Good point. There are other tricks to make it slide continuously without ever tightening the knot though, should one wish. (I'll post later).

Also, extension causing "shock loading" and "significantly" higher forces has been debunked a long time ago. Jim Ewing at Sterling Ropes conducted load cell testing completely disproving the idea, showing there is almost no concern over small amounts of extension (a foot or less), that overall force was not increased during tests where a piece blew, and that "shock loading" is a vague term that doesn't apply to a system involving an elastic climbing rope.
Read Climbing Anchors by John Long. All that testing is in the book, the book which starting all this new anchor discussion.
Finally, This thing is suposed to extend if a piece blows. Not very much, that's the whole point of limiter knots and using this double Figure 8 as only a small part of the rig.
But nonetheless, I'm proposing the use of the double 8 based on the premise that you're up to date on the subject of small extension being OK, and moved on.
We're talking about starting with an equalette here, so if you don't like anything sliding with the understanding that some extension is inherent, then there's not much more to discuss (without repeating other, older threads).

See this thread for discussion on sliding X's, limiter knots and shock loading:
http://www.rockclimbing.com/...um.cgi?post=1306133;

And further details on the testing done:
http://www.supertopo.com/...id=307091&tn=108


(This post was edited by Neoshade on Aug 18, 2011, 1:30 AM)


patto


Aug 18, 2011, 2:49 AM
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Re: [Neoshade] Stupid Simple Elette [In reply to]
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Neoshade wrote:
Also, extension causing "shock loading" and "significantly" higher forces has been debunked a long time ago. Jim Ewing at Sterling Ropes conducted load cell testing completely disproving the idea, showing there is almost no concern over small amounts of extension (a foot or less), that overall force was not increased during tests where a piece blew, and that "shock loading" is a vague term that doesn't apply to a system involving an elastic climbing rope.
Read Climbing Anchors by John Long. All that testing is in the book, the book which starting all this new anchor discussion.

Thinking that shock loading has been debunked is highly dangerous! It has not been. Shock loads can easily result in forces 10-20 times higher, this has been shown repeatedly in testing*. *Testing of masses taking high factor falls on static cord/sling.

The testing discussed was fundamentally flawed as there was no mass on the belay. High school physics would tell you that without a mass on the belay the 'shock loading' isn't a problem. However as soon as you add a mass to the belay such as a 80kg belayer then suddenly extension on the anchor becomes a big concern.

As far as your design goes Neoshade I have no issue with it. However I do wish to impress upon you and others that J. Long's book is highly misleading regarding 'debunking' shock loading.

Anyway I'll try to step away from the discussion. Smile


(This post was edited by patto on Aug 18, 2011, 8:49 AM)


JimTitt


Aug 18, 2011, 3:24 AM
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Re: [Neoshade] Stupid Simple Elette [In reply to]
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Canīt see itīs equalised anyway, looks like 50/25/25 to me.
Equalising the right pieces by nylon sliding on nylon, youīre joking right?
Increased loading with increasing extension is inevitable, is real and not to be ignored.
Use the rope or clove hitches.

Jim


billl7


Aug 18, 2011, 5:59 AM
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JimTitt wrote:
Canīt see itīs equalised anyway, looks like 50/25/25 to me.
Equalising the right pieces by nylon sliding on nylon, youīre joking right?
Increased loading with increasing extension is inevitable, is real and not to be ignored.
Use the rope or clove hitches.

Jim

+1 on all the above points.

I used the equalette and a variation of it for quite a while. I've pretty much gone back to simpler means.

It is worth repeating that the primary anchor quality is bomber individual pieces. If there aren't good placements: continue the climb until there are, downclimb until there are, bail on a couple of the iffy placements*, or consider finding a very good stance and hope your partner won't be too pissed.

Bill L

* Edit: If you really feel like you've gotten yourself into a situation where you must use them, equalize two or three and rap (endanger only yourself).


(This post was edited by billl7 on Aug 18, 2011, 6:31 AM)


dan2see


Aug 18, 2011, 6:53 AM
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Re: [Neoshade] Stupid Simple Elette [In reply to]
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Thanks for showing us your alternate method for anchor-building. Ideas like this are interesting and should always be analyzed.

But ... (hey you knew there'd be a "but")

Sometimes I'll try something, but every time I get creative, I get into trouble. It's not worth it.

So when I see a pair of bolts, I make an equalette or "X", and on gear I stick to cordalette.

No fooling around, stick to standard methods. Get it done and get it on.


kaizen


Aug 18, 2011, 7:08 AM
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Re: [patto] Stupid Simple Elette [In reply to]
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patto wrote:
Thinking that shock loading has been debunked is highly dangerous! It has not been. Shock loads can easily result in forces 10-20 times higher, this has been shown repeatedly in testing.

The testing discussed was fundamentally flawed as there was no mass on the belay. High school physics would tell you that without a mass on the belay the 'shock loading' isn't a problem. However as soon as you add a mass to the belay such as a 80kg belayer then suddenly extension on the anchor becomes a big concern.

Patto - do you have any reference for these subsequent tests? I've seen you post this in other threads, and have yet to find any further tests that back up that statement. Not trying to pick a fight, just genuinely curious what you're referencing.


Partner rgold


Aug 18, 2011, 8:02 AM
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There are no further tests that I know of. (*) Patto's comment is based on the description of the original tests, which makes it absolutely clear that (1) they do not model what can happen with a factor-2 leader fall onto the anchor in the real world, because, as he says, the tests contained no mass corresponding to the belayer, and (2) the dismissive results of the tests as performed were easily predictable from the set-up.

The tests modeled a rope soloing fall of the climber onto an anchor that extends. The extension in the anchor was very small compared to the amount of rope in the system for absorbing fall energy, so it is no surprise that the conclusion was that the anchor extension mattered little.

Having a mass corresponding to the belayer is critical, because if the belayer is dragged off the stance, the only part of the system absorbing that fall energy is the belayer's tie-in, and the length of that relative to anchor extension could be small enough to result in much increased anchor loads.

(*) Edit: From Jim Titt in Germany:

Well, as usual the DAV have done this one (Panorama 2/2009, also interesting for the dynamic and static tests on various sling materials tied with a clove hitch).

5m drop, 80kg, dynamic rope belayed with HMS on sliding X with 60cm legs. Hanging belayer weight 65kg.

Single leg failure gave 40% higher force than the same test with no extension.


Of course, results like this were predictable and were predicted.

As for this anchor, it is a variation in the highly non-equalizing genre of 50/25/25 configurations, using a figure-8 variation instead of clove hitches to possibly getting better distribution to the two low-load pieces. If you need equalization, the ACR is a better bet. The rest of the time, I'd go with the rope by itself or (say on a wall) the classical cordelette.


(This post was edited by rgold on Aug 18, 2011, 8:41 AM)


JimTitt


Aug 18, 2011, 8:39 AM
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As Iīve posted elswhere:-

Well, as usual the DAV have done this one (Panorama 2/2009, also interesting for the dynamic and static tests on various sling materials tied with a clove hitch).

5m drop, 80kg, dynamic rope belayed with HMS on sliding X with 60cm legs. Hanging belayer weight 65kg.

Single leg failure gave 40% higher force than the same test with no extension.

I wish John Long would sort his book out, generations of climbers have survived without all this (and his) pure speculation and half-baked ideas, though equalising by movement inside a knot has probably got to be the stupidest idea yet.

Jim


patto


Aug 18, 2011, 8:57 AM
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kaizen wrote:
Patto - do you have any reference for these subsequent tests? I've seen you post this in other threads, and have yet to find any further tests that back up that statement. Not trying to pick a fight, just genuinely curious what you're referencing.

I was more referring to the many tests of short falls onto static slings/cord. FF2 falls can result in 20x the forces. In the case of extension you are more likely looking around FF0.5 falls. The effects of shock loading a thus lower but still quite significant in the case of sling/cord.

JimTitt wrote:
I wish John Long would sort his book out, generations of climbers have survived without all this (and his) pure speculation and half-baked ideas, though equalising by movement inside a knot has probably got to be the stupidest idea yet.

I'm glad somebody else has said it. I've been banging on about this for years but we continue to get new 'elettes' being invented based on a false premise.


kaizen


Aug 18, 2011, 9:39 AM
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Re: [rgold] Stupid Simple Elette [In reply to]
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rgold wrote:
There are no further tests that I know of. (*) Patto's comment is based on the description of the original tests, which makes it absolutely clear that (1) they do not model what can happen with a factor-2 leader fall onto the anchor in the real world, because, as he says, the tests contained no mass corresponding to the belayer, and (2) the dismissive results of the tests as performed were easily predictable from the set-up.

The tests modeled a rope soloing fall of the climber onto an anchor that extends. The extension in the anchor was very small compared to the amount of rope in the system for absorbing fall energy, so it is no surprise that the conclusion was that the anchor extension mattered little.

Having a mass corresponding to the belayer is critical, because if the belayer is dragged off the stance, the only part of the system absorbing that fall energy is the belayer's tie-in, and the length of that relative to anchor extension could be small enough to result in much increased anchor loads.

(*) Edit: From Jim Titt in Germany:

Well, as usual the DAV have done this one (Panorama 2/2009, also interesting for the dynamic and static tests on various sling materials tied with a clove hitch).

5m drop, 80kg, dynamic rope belayed with HMS on sliding X with 60cm legs. Hanging belayer weight 65kg.

Single leg failure gave 40% higher force than the same test with no extension.


Of course, results like this were predictable and were predicted.

As for this anchor, it is a variation in the highly non-equalizing genre of 50/25/25 configurations, using a figure-8 variation instead of clove hitches to possibly getting better distribution to the two low-load pieces. If you need equalization, the ACR is a better bet. The rest of the time, I'd go with the rope by itself or (say on a wall) the classical cordelette.

RGold, thank you for this concise response, it is greatly appreciated.

Jim - do you know if there is an online publication of the study you mention?

Thanks for the explanation Patto.


Neoshade


Aug 18, 2011, 9:40 AM
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JimTitt wrote:
Canīt see itīs equalised anyway, looks like 50/25/25 to me.
Jim

Wow. Big apologies. That was just blatantly stupid of me. I completely failed to address some major issues, and I definitely over-claimed the whole self-equalizing properties of this.
Also, sorry Patto for getting preachy and aggressive when I was treating John Long's work and the extension testing like gospel and just beating the bible at you. I think the community at large needs better, more extensive testing much more that it needs new rigging ideas in order to move forward right now.

1) It is not perfectly equalized. It's definitely a 50/25/25. I find that is OK myself, as most of my real world placements have better pro and sketchier pro, and offsetting the load is handy.
Also note that you can tie the same knot in both legs for a 25/25/25/25.

2)The double 8 is definitely not self-equalizing in the classic sense, as it's a knot in the cord, and not a carabiner or ring sliding along the cord. So, to be more precise, this knot will adjust itself a good amount while still loose, a nice advantage over clove hitches.

JimTitt wrote:
Equalising the right pieces by nylon sliding on nylon, youīre joking right?
Jim

Yes, it's nylon on nylon, but that's actually pretty normal use for cord/rope. We're not talking about lowering off a sling, but rather casual sliding of the knot during belay, and a small amount of slippage as it's loaded. That's not very dangerous or uncommon. Think Munter Hitch or the cinching of your harness knot during the first fall or take. That's all. No crazy friction danger here. Also, I like double 8 here only as a smaller knot. However there are people that have been climbing on full size Double 8 anchors for a while. (ie: Ultrabiker)

So what I mean to say, is that the Double 8 is a quick and versatile replacement for cloves on additional pro. It can also be adjusted at any time very easily, and less importantly, it will somewhat self-equalize while the knot is still loose. Further slippage of the knot under load for a dynamic equalization is possible, but I can't say without more research & testing. (I really need to see how the knot slips or equalizes under fall loads, that's very important to know. Right now I only believe it slips an inch or so and equalizes. But that remains to be seen for a sloppy knot and for small Vs large forces.)
I'd really love to hear from anyone that has used Ultrabiker's Fig 8 for the entire anchor rig, or who has any further experience with the knot.

JimTitt wrote:
Increased loading with increasing extension is inevitable, is real and not to be ignored.
Use the rope or clove hitches.


As far as small extension (4-10") and increased loading goes, that is going to need some serious looking into. My entire concept is based on small extension being OK, and Jim Ewing's testing and John Long's opinions being valid. If the equalette & limited Sliding-X is debunked as dangerous for reasons of extension, then we all need to go back to cordalettes, manual equalizing, and bomber MP knots.
However, the Double 8 needs its own testing to see if it slips a little (self-equalizing) or tightens up bomber under high fall loads. Really, I want to address this so badly, please pardon my lack of info.

JimTitt wrote:
Well, as usual the DAV have done this one (Panorama 2/2009, also interesting for the dynamic and static tests on various sling materials tied with a clove hitch).

5m drop, 80kg, dynamic rope belayed with HMS on sliding X with 60cm legs. Hanging belayer weight 65kg.

Well shucks, I feel like being a John Long believer is now a black mark upon my soul. :-/
Did they use limiter knots? Or was the extension a full meter or so?
I'd really like to see the data if you can find it. I'm still a little unsure how the FF are so high for small extensions. Is the rope under full stretch at the time and no longer helping?

Thanks again all for the input, I really want to know more about the Double 8 and how it takes falls.
I still think it's a nice improvement over cloves. (in the world of acceptable equalizing & extension)


(This post was edited by Neoshade on Aug 18, 2011, 9:51 AM)


hugepedro


Aug 18, 2011, 10:08 AM
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Re: [JimTitt] Stupid Simple Elette [In reply to]
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JimTitt wrote:
Canīt see itīs equalised anyway, looks like 50/25/25 to me.
Equalising the right pieces by nylon sliding on nylon, youīre joking right?
Increased loading with increasing extension is inevitable, is real and not to be ignored.
Use the rope or clove hitches.

Jim

Definitely not equalized, so this business about the knot equalizing is just silly, even if it were desireable to have it do so (which, as you point out, it is not).

But, I don't care about 50/25/25. Most anchors never take the force equally in real world falls anyway. I'll take bomber pieces and a good stance over dynamic equalization any day.


JimTitt


Aug 18, 2011, 10:17 AM
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Re: [Neoshade] Stupid Simple Elette [In reply to]
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The whole equalising knot thing is madness, first you really ought to know that the friction of nylon on nylon is relatively high, 2.5 times that of nylon on metal so you are in the shit there with any thought of equalising anyway. And when one piece blows either the knot unravels, gets cut by the loaded strand sliding through (nothing like a Munter by the way) or whatever but you donīt know.
So, like others, you are publicising a system which you have sketchily though through, with no theoretical justification and no testing either, in other words you have no idea what will happen. Super, we know other people like that!

Of course there were no limiting knots, I would have written "a limited extension sliding X" if that had been the case. The extension was 60cm as this was the length of the failed leg and to get those sort of force increases dropping a belayer 60cm onto a sling is very understandable.

The article was referenced but if you really need a link to get into the biggest database of climbing safety related articles it is http://alpenverein.de/...r.php?tplpage_id=165 and you go through the archive to 2/2009 and download the pdf.

Jim


Neoshade


Aug 18, 2011, 11:08 AM
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Re: [patto] Stupid Simple Elette [In reply to]
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So, In the interest of "dynamic equlization" (which a knot really can't claim) I thought I'd take a whack at the hornets' nest :D

Haters be hatin', so...
Yo Dawg! I heard you like Sliding-X's...
So put I a Sliding-X on yo' Sliding-X!





Now THAT'S a handy little truly-self-equalizing leg on a cordalette (or equalette in this case).
Seriously, the Double-8 is a pretty sweet and versatile knot!

Enjoy. (And bring on the hate Wink)


vencido


Aug 18, 2011, 12:00 PM
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Re: [Neoshade] Stupid Simple Elette [In reply to]
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If I get hooked up with a partner that has a big hunk of accesory cord tied together with a double fisherman's and then extra fisherman stopper knots (tied 3" from the end of the main knot) I'll quickly come to the conclusion that he tends to waste time and overthink things.

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