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roy_hinkley_jr
Feb 24, 2006, 5:45 PM
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In reply to: In reply to: Sounds like a new generation of dangerous climbers is about to be created...they think they're being "safe" while actually creating more problems than they solve. Huh? Please provide input.
Climbers growing up in the new paradigm will spend 20 minutes rigging every belay...they'll get confused by too many options...they still won't understand the forces, vectors, and limitations...they'll create new failure points never imagined (cross-loaded biners, etc)...they'll insist anyone not using their uber-cluster is "unsafe"...they won't know what to do when they reach a belay and don't have the required 6 slings and 15 carabiners (anodized only of course)...and in the end, accident rates will remain exactly where they were 20 years ago.
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gordo
Feb 24, 2006, 5:57 PM
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In reply to: With the limiter knots in the sling (for a single modified sliding X) it doesn't even need the X. In reply to: I disagree. Still using the x makes the center redundant as well. Now if you have 2 total systems this isn't important, but for me I don't want to be 100% dependent on the one strand of the center either. I know, I know...never heard of one breaking...call me Paranoid (I am) Did you mean quad? Duo-glide is the so last week name for the equalette. :lol:
Yep, that's what I mean. I'll go back and edit that. Thanks.
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crotch
Feb 24, 2006, 6:23 PM
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I know that there are a million ways to build an anchor, but here's another rigging option for 3-piece equalization.
http://www.rockclimbing.com/...p.cgi?Detailed=69832
This setup for a 3-piece anchor requires only 1 special piece of gear, a screamer. If either placement 1 or 3 blows, placement 2 with the screamer will only feel the screamer activation force (2 kN for a standard Yates screamer) while the magic-X extends to the limiter knot. Once full extension is reached, the load should be shared between the remaining two pieces.
The drawback I see is that the screamered piece (2) would bear only the screamer activation force with the other placement taking the rest of the load. You could change how much load is taken by the screamered piece by using two screamers in parallel, or a special screamer with a higher activation force.
What do y'all think?
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landgolier
Feb 24, 2006, 6:26 PM
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In reply to: This just in: The field testers just told me that that picture featuring the unweighted arms of the Equalette is not strictly accurate because the master point was not sufficiently weighted, or weighted at all. When the master point is weighted--as with a belayer's body weight--and off axis loading occurs, the master point slips toward the directional of pull and equalization--across all four placements--is maintained.
Not that I want to get into it with the master and his minions (j/k), but this is obviously untrue. Each side of the equalette is just two single lines going from one master point to two protection points. It's a two arm cordelette. Granted it's a very well-adjusted one since you can dial in the cloves, and if the pieces are close you will never really notice the slack, but you still have a triangle with 3 fixed side lengths. You can't move one of its verticies within that plane and expect the side lengths to stay the same. It's just like hanging off a two bolt anchor (with horizontal bolts) by two draws or whatever. You can move up and down, but lean to one side and all the weight goes onto one bolt (the one on the opposite side from the direction you leaned).
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gordo
Feb 24, 2006, 6:56 PM
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In reply to: In reply to: This just in: The field testers just told me that that picture featuring the unweighted arms of the Equalette is not strictly accurate because the master point was not sufficiently weighted, or weighted at all. When the master point is weighted--as with a belayer's body weight--and off axis loading occurs, the master point slips toward the directional of pull and equalization--across all four placements--is maintained. Not that I want to get into it with the master and his minions (j/k), but this is obviously untrue. Each side of the equalette is just two single lines going from one master point to two protection points. It's a two arm cordelette. Granted it's a very well-adjusted one since you can dial in the cloves, and if the pieces are close you will never really notice the slack, but you still have a triangle with 3 fixed side lengths. You can't move one of its verticies within that plane and expect the side lengths to stay the same. It's just like hanging off a two bolt anchor (with horizontal bolts) by two draws or whatever. You can move up and down, but lean to one side and all the weight goes onto one bolt (the one on the opposite side from the direction you leaned) .
No, not really. You leave out the sliding part in the middle. If you do the equalette off of those same 2 bolts it is perfectly equalized. You can move the power point all over (of course within reason) and it's still good. Now when you throw in the 3rd and 4th placements...as has been said before....moving the power point off center does (can?) unweight one piece on each side, but the 2 sides are still equalized. WAY better than 2 draws.
Equalette on 2 bolts: Equallized as well as a sliding X
http://members.cox.net/.../6299DuoGlideon2.jpg
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bergman
Feb 24, 2006, 6:59 PM
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In reply to: In reply to: In reply to: Sounds like a new generation of dangerous climbers is about to be created...they think they're being "safe" while actually creating more problems than they solve. Huh? Please provide input. Climbers growing up in the new paradigm will spend 20 minutes rigging every belay...they'll get confused by too many options...they still won't understand the forces, vectors, and limitations...they'll create new failure points never imagined (cross-loaded biners, etc)...they'll insist anyone not using their uber-cluster is "unsafe"...they won't know what to do when they reach a belay and don't have the required 6 slings and 15 carabiners (anodized only of course)...and in the end, accident rates will remain exactly where they were 20 years ago.
Ah, there's a refreshing viewpoint.
I've been following this thread closely, and it's been fascinating and of a terrific quality. I'd like to thank everyone who's contributed, especially L.
The geeky math/physics/gear part of me is really interested in the various rigging options, and the hair-splitting differences between them.
However...I strongly think that any major revamping of recommended best practices for anchors should rest on a foundation of actual problems with anchors, more than with physics. For example, over the last 5~10 years, as cordelttes and webolettes became popular, has the failure rate of anchors gone up, and is the a common failure mode that will be addressed by an anchor with better active equalization?
Think of the "80/20" rule...if 80 percent of current accidents invoving an anchor are not due to the inherent problems with a cordelette, then how much effort should be put into changing the recommended style of anchor, with the cost of greater complexity? For example, if the most common causes of anchor-related accidents are (hypothetically speaking) (1)catastrophic failure of Alien cams and (2) belayer accidently cuts anchor cordellete at powerpoint while trying to slice tuna sandwich, then a new form of highly equalized anchor, improved as it is, won't solve the common problems.
For me, the primary qualities in an anchor are (in order of importance):
1. placement quality. (is each peice, or the sum of the pieces, bomber) Think the
"S" in SRENE
2. Redundant
3. verifiability of the rigging (if the placements and rigging are too complicated to be
certain of their quality, then the potential for a mistake or single point of failure is
very high). For me, this is KISS, and is highly important when it's cold/dark/
about to rain, or when there's any other high-stress situation.
4. Equalized
5. No (reduced) Extension
6. Fast. I want an anchor system that I can repeatedly set up quickly, with a
high assurance of meeting the first 3 qualities.
7. Gear-efficient. I don't want to carry more gear than needed, nor do I want to
only be familiar with certain types of anchors (ie., if I dropped the cordellete or
the 2x 4' slings, or the chain of extra locking biners, etc. at the previous belay,
I need to be versed in different anchor techniques so that I'm able to set up
something safe with what I've got on me when I reach spot where I'll build
the anchor).
Personally, I'm absolutely convinced about changing my method of attaching myself to the anchor, so that I always use the rope as my primary attachment. However, at the moment, I'm still comfortable with a webolette or cordelette, with the equalization problems, if it allows me to build an anchor that has a better chance of satisfying criteria 1, 2, & 3 above.
I'll look closely at new systems, but KISS rates really high for me...personally I think that there's a greater chance of screwing up "complicated" rigging and having an anchor fail under a moderate load, then there is in having a system with imperfect and static equalization fail under the same moderate load (ie., 4~8' factor 1 fall with the belay off the belayer's waist, redirected through the powerpoint or through a separate piece about the height of the highest anchor point). I guess I just don't climb hard enough to think of a trad FF2 fall as being likely for me or my partner. :)
Realize that the people posting to this thread may be in the top 10% (1%?!) of folks who think about the angles & forces & consequences involved in an anchor. If there's this much discussion and head-scratching going on, what are the odds that someone less thoughtful and experienced will get it wrong out on the rock, when they are tired & hungry & have to pee & in a hurry. Think about how many newbies don't get the idea of the basic sliding-X, and then think about how "intuitive" a cordelette anchor is. Sure, under the true load of a fall, it's not equalized, but when it's being set, the climber can tug at it, and hand-load the powerpoint, and its easy to verify.
Thanks again for all the thought & testing that has gone into this discussion.
Mark
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hemp22
Feb 24, 2006, 7:04 PM
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gordo, I think landgolier is referring to only 1 side of the Equalette when he's saying it's like 2 draws.
The 2 sides of the equalette definitely equalize, but within either one of those two sides, there's not necessarily equalization, especially when the strands are different lengths and the direction of pull is changed.
Each strand is a fixed length between the limiter knot & the clove hitch - that's why each individual side of the Equalette is similar to a 2-piece Cordolette.
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gordo
Feb 24, 2006, 7:09 PM
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Mark....can I sum up your thoughts this way?: "Even though the guy who made the Cordolette mainstream says tests (not physics) prove beyond doubt that the cordolette does not equalize, but rather weights one piece only, I'm still going to use it because cordolette failure is not a major cause of anchor failure."???
Now we're all welcome to our ideas of what's simple and what is good for each of us. And I don't want to be flameing or busting on anybody. But this just doesn't make sense to me.
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gordo
Feb 24, 2006, 7:12 PM
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In reply to: gordo, I think landgolier is referring to only 1 side of the Equalette when he's saying it's like 2 draws. The 2 sides of the equalette definitely equalize, but within either one of those two sides, there's not necessarily equalization, especially when the strands are different lengths and the direction of pull is changed. Each strand is a fixed length between the limiter knot & the clove hitch - that's why each individual side of the Equalette is similar to a 2-piece Cordolette.
I tried to read it that way but couldn't see it. If I was wrong I appologize. That is true.
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landgolier
Feb 24, 2006, 7:17 PM
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In reply to: gordo, I think landgolier is referring to only 1 side of the Equalette when he's saying it's like 2 draws. The 2 sides of the equalette definitely equalize, but within either one of those two sides, there's not necessarily equalization, especially when the strands are different lengths and the direction of pull is changed. Each strand is a fixed length between the limiter knot & the clove hitch - that's why each individual side of the Equalette is similar to a 2-piece Cordolette.
^What he said^
I wonder if the end result of this is going to be that 4 anchor points become way more industry standard than 3. The equalette is of course totally good to go with only 3 points, but still, I'm betting people mostly start using 4.
Also, has anybody monkeyed with different ways to put in an upward pull piece? You could use one of the 4 arms for that if you had enough slack, but you get a lot of motion before it kicks in, whereas I like my upward pieces to be on a pretty short leash. I guess you could just put a sling into the PP biners, but has anybody had any fancy ideas about this?
Now back to rigging anchors off the hooks in the gear closet...
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dominic7
Feb 24, 2006, 8:39 PM
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In reply to: I like the simplicity of the equalette, but still have a couple questions/concerns. First: why the two lockers? I understand that (A) you wouldn't want to just clip one of the 2 strands between the limiter knots, because if that strand cuts you're toast, and (B) you also wouldn't want to just clip around the two strands together, because then if one side of the Equalette completely blows, then your locker slides off that end. But why not just put a half twist into one of the strands between the limiter knots, and then clip the biner through that loop and the other strand, just like we do w/ a sliding X?
From a KISS perspective I can see people slapping a locker around both, figuring two strands is better than one, and being vulnerable to B) above. Is the consensus that straight clipping both strands (without a sliding X crossover in one strand) is a Bad Thing (tm)?
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landgolier
Feb 24, 2006, 8:42 PM
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In reply to: From a KISS perspective I can see people slapping a locker around both, figuring two strands is better than one, and being vulnerable to B) above. Is the consensus that straight clipping both strands (without a sliding X crossover in one strand) is a Bad Thing (tm)?
Roger that, can confirm that taking the big ride when only half your anchor blew is a Bad Thing™
over and out
Edit: Wait, what are you asking? There's no way to clip both with a single biner without an X and not be vulnerable to option B. Do you mean just clip one strand?
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healyje
Feb 24, 2006, 9:16 PM
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In reply to: In reply to: From a KISS perspective I can see people slapping a locker around both, figuring two strands is better than one, and being vulnerable to B) above. Is the consensus that straight clipping both strands (without a sliding X crossover in one strand) is a Bad Thing (tm)? Roger that, can confirm that taking the big ride when only half your anchor blew is a Bad Thing™ over and out Edit: Wait, what are you asking? There's no way to clip both with a single biner without an X and not be vulnerable to option B. Do you mean just clip one strand?
I agree that is the biggest potential for screwing the pooch. How to construct the power point would need to be emphatically and explicitly clear in any presentation of the technique and it will still happen again and again in the real world.
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rgold
Feb 24, 2006, 9:27 PM
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Here is another example of a non-equalizing anchor
http://www.rockclimbing.com/...p.cgi?Detailed=69924
I think we need some better terminology here. Anchors can be broadly divided into two classes, orientable and non-orientable, depending on whether or not the power point can shift to accomodate different load directions. Among the orientable anchors, there are two types, distributed orientable and equalizing. The distributed orientable anchors are one like the one pictured, that distribute the load without equalizing it, and the equalizing anchors are ones that, because of some pulley system, equalize the load to the anchor points.
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rgold
Feb 24, 2006, 9:30 PM
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Here's a variation on some of the themes mentioned already.
http://www.rockclimbing.com/...p.cgi?Detailed=69926
John will hate the rap rings (please do not try this with the rolled aluminum kind) but they seem better to me than using up even more biners, and they do have other uses. The sling in the equalizer is a two-foot Mammut runner. The same system will handle two or four anchors (with another rap ring), and there is, perhaps, some advantage in having a single system that can be used for all situations in which you want true equalizing anchor.
I didn't have a cord cordelette for the picture, and I wouldn't use the webolette for this purpose in real life, because I'm not sure how clove hitches in webbing perform. The webolette is tied so that each anchor is connected to the equalizer with a single load strand, avoiding the load doubling that some posters have created. The slack left in between successive connections needs to be long enough to accomodate proper extension if that were to happen. The pictured equalizer will extend two inches if a piece blows. The same thing could be tied with the equalizer and the climbing rope too.
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rgold
Feb 24, 2006, 9:33 PM
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Double post
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rgold
Feb 24, 2006, 9:34 PM
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*&^%$#! Triple post.
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roy_hinkley_jr
Feb 24, 2006, 9:46 PM
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In reply to: For example, over the last 5~10 years, as cordelttes and webolettes became popular, has the failure rate of anchors gone up, and is the a common failure mode that will be addressed by an anchor with better active equalization?
Belay anchor failures have, fortunately, always been very rare. I can only recall two in the US during that time frame. The one in Sedona? where 3 took the big ride and the Tahquitz fall where 2 plunged. IIRC the first was attributed to something going wrong before the anchor was fully rigged. And the second was likely the fault of the cordelette system. No surviors to tell the tales though. Anyone know of other incidents in Europe or elsewhere?
Rap and TR anchor failures are more common but those aren't due to high forces, just inattention (usually).
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rgold
Feb 24, 2006, 9:48 PM
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OMG. None of the previous three showed up when I tried posting. Now they're all here. Argh. Quadruple post, a new record.
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glowering
Feb 24, 2006, 9:54 PM
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Couldn't you just eliminate the rap rings on the bottom equalizer?
It seems the sliding W (three leg magix X with no limiter knots which would kill the equalization) or the gordolette (which I haven't tried yet) is the only way shown so far to truly equalize among 3 placements.
If you build the sliding W with a short runner under three static extensions to the pieces you'd get equalization with low extension.
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healyje
Feb 24, 2006, 10:12 PM
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RGold,
That's another good go at a firewalled rig. This is a -2x version of Dr_Monkey's rig a few pages back: I haven't set either up and will when I get home. Like I said, I certainly see the logic in putting a firewall between extension and equalization but I still have my doubts about the ultimate efficacy and utility of doing so given the hardware required. I'd probably just lose the rings as well and go straight through the biner. I bet in real application the difference would be of negligable impact on the net results. Also not sure that I wouldn't just use three [trad] draws and a slightly longer equalizing piece to make it.
Dr_Monkey photo:
http://i42.photobucket.com/...erdavid/DSCN0082.jpg
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maldaly
Feb 24, 2006, 10:40 PM
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roy_hinckley_jr has a pretty good point here. I just am not aware of too many anchor failures. The one in the Sandias (rhj thought it was Sedona) where a cordelette-equalized anchor failed and the Tahquitz one. 20 or so years ago some guys died when a haul bag was kicked off while thewy were rapping the Cap, and fully shock-loaded the American Triangle to 1/4 inch bolts they were hanging from. I see tons of people climbing around with multiple cordalettes and a half-dozen lockers yet the accidents I read about are from getting lowered off the end of a rope or whacking a helmetless head. I put in a call to Jed Williamson, the editor of Accidents in North American Mountainering, who compiles most all of the accidents that happen in N. America. I'm going to ask him if he's compiled the stat's across the years. At the end of each year's book he compiles that year's reasons but it would be super interesting to see how they look across the years. When I informally interview the OTDs I know, virtually none of them use cordalettes when they're just craggin around. Largo, do you cordalette your anchors when you're cragging with your buds? I surely don't.
Here's what I've been doing for 35 years: each climber carries a 48" runner for the belays. At the anchor I EQ two downward pulling pieces with a sliding X. If there's enough sling I tie a limiter knot. I clip into that with my rope. Then I place a good upward piece and tension the anchor points together with with a clove. If any of the pieces are suspect at all, I'll back it up with one or two other EQ'd downward pull pieces then tie into that with the rope.
Mal
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healyje
Feb 24, 2006, 10:54 PM
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Sometimes when I hit a two bolt anchor I clove my rope to a biner on one anchor and put a [trad] draw on the other. I then clove the other end of the draw into the section of rope between me and the first anchor I cloved. That creates a triangle out the draw and the section of rope between the draw clove and the anchor clove.
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glowering
Feb 24, 2006, 11:34 PM
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There was an anchor failure on the DNB a few years ago.
I think the point of this thread is that, yes there are simple methods to build an anchor off two good pieces (sliding X with limiter knots), but more experienced climbers are going to run into a lot of situations and the more tools in the kit the better.
Personally I don't like to build the rope into the anchor since I often lead in blocks and also it would slow down the self-rescue procedure (build new anchor, extract rope).
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healyje
Feb 24, 2006, 11:41 PM
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Yah, I only do it swing leads out cragging. Quick and dirty.
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