Self-equalizing vs. static anchor
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 Mar 30, 2011 So I am weighing the pros and cons of a self equalizing anchor system (like the sliding X or ACR) vs. a static anchor (Coordilett equalized, then tied off.) The self equalizing self equalizes but if one pice blows it will shock load the others. In the static system if one piece blows it does not shockload the others but the equalization is far from perfect. Thoughts? J macJoined Oct 8, 2008104 points
 Mar 30, 2011 anchors 101: SRENE Solid Redundant Equalized NO EXTENSIONS my \$.02 edit: i guess it also matters on whether you're talking about trad protection or bolts. and whether you're going to just be top roping from the anchor or leading up another pitch above it. T.L. KushnerJoined May 21, 20097 points
 Mar 30, 2011 I'm curious why you say a 'static' system can't be equalized? kpboFrom Fort Collins, COJoined May 25, 200810 points
 Mar 30, 2011 I couldn't have said it better than Dave. Including the book recommendation! I would only use a sliding X if the pitch wandered back and forth a lot. Otherwise, equalize and tie a knot. Gif ZafredFrom Pittsburgh, PAJoined Nov 30, 201041 points
 Mar 30, 2011 The solid rock & solid pro using good angles are the critical parts. The rigging method is trying to match your intended direction of travel to load distribution off of multiple points. You're not getting perfect equalization in any case and you're not working for redundancy. However with the dynamic rope, you won't see anything high enough nor will you get "shockloading". Ultimately, your rope will fail before a solid anchor will. If the anchor failed, the pro wasn't solid and/or had exaggerated angles. Buff JohnsonJoined Dec 19, 20051,504 points
 Mar 30, 2011 With correctly tied limiter knots, extension is not much of a problem. To obtain a full 360 degree circle of use from two points, limiter knots should not be any further apart than the distance between the two points of protection, any extra serves no purpose. They should also be centred about the midpoint between the two points. With this method, the maximum extension you can ever get is the distance between the two points of protection (for a sideways pull), and the more probable extension is half that distance (for a downwards or upwards pull). So for a typical bolted anchor which might be two bolts spaced 2 feet apart. You shouldn't ever be looking at more than 1 ft of possible extension. It also helps to tie the knots so that one strand of your x is slightly shorter than the other. This lets the midpoint slide more easily I find because the strands don't bunch up against each other. DannyUncannyFrom VancouverJoined Aug 27, 201078 points
 Mar 30, 2011 equalette rather than cordolette. The testing results near the end of Long's book shows significant advantages. The equalette also provides more lattitude in terms of equalizing falls where the load isn't perfectly aligned with the expected direction of fall (when setting the anchor). Dan HallJoined Jun 15, 20100 points
 AdministratorMar 30, 2011 I second what Yarp said, except buy Luebben's book and read it 3 or 4 times. Matthew FienupFrom Ventura, CAJoined Feb 18, 20067,448 points
 Mar 30, 2011 Pesterfield's book was pretty good too. Many, many others out there. Reading them all would be the best advice if you don't have anyone to help you out as you learn. YarpJoined Jan 16, 20116 points
 Mar 31, 2011 Buy both the Gaines/Long 2nd ed Anchors AND Leubben's Anchors books. They both cover things the other one does not or only touches upon. Gaines/Long has test results via Sterling on anchor loading and "shock" loading. I like Leubben for the clarity of images and more up to date equipment. Gaines/Long covers REAL anchor "philosophy" better. SERNE is kind of a "myth" in many ways. Both are worth the read. mattmFrom TXJoined Jun 2, 20061,278 points
 Mar 31, 2011 SRENE is an oxymoron. You can never have full equalization without facing some extension. Period. A better goal is SRELE. Simple Redundant (massively misunderstood by the community) Equalized LITTLE Extension Sliding-X: Equalized, simple. NOT redundant (single cut failure mode on the sling) unless you tie limiter knots, or clove hitches at the pieces. NOT low extension unless you have a short sling or tie limiter knots (which limit the range of equalization). I still would knot kill my partner if her used a single good sling on a double bolt anchor, but I personally double them up the slings on the rare occasions I have used them. Cordalette: Lots of discussion on these is already overkill. Very limited equalization, little to no extension, good redundancy (you can cut any 2 cords or pull 2 pieces of gear before failure). With good gear and mostly straight up and down routes it is still a very good solution for many anchor situations. Equallete: Hybrid sliding X that trades a little extension for a region of equalization. Each half is statically equalized with a sliding-X in the middle equalizing those dynamically. The region of equalization is limited, especially on big-walls where you may need the anchor to hold horizontal loads as your partner cleans the last pitch, yet still be bomber for vertical loads once you start the next pitch. ACR/Trango Equalizer: Equalization, but NO redundancy to cutting of the sling/cord. Extension is possible unless you use limiter knots. ACR/Trango Equalizer with Clove Hitches on each piece: Slight reduction is equalization (50% max load vs. 33% without clove hitches), but you immediately get Low extension, and double redundancy (handles 2 cuts and/or 2 pieces blowing, though the extension can be large if two pieces blow). Rope cloved in: Can be statically equalizied (i.e. 0-100% load on each piece depending on millimeters of error on the knot locations). Zero redundancy for cut rope (we accept this at all times when climbing with single ropes), but as much redundancy as you have extra pieces in. Works well with vertical cracks, poorly for horizontal (greatly effects extension and equalization). Summary: Learn lots of methods, especially the underlying strengths/weaknesses. Approach each anchor with a keen eye towards would could go wrong and be prepared to modify your usual approach to assure that every anchor you make will keep you and your partner off the deck. MoofFrom Portland, ORJoined Dec 11, 200715 points
 Mar 31, 2011 Moof wrote: Rope cloved in: Can be statically equalizied (i.e. 0-100% load on each piece depending on millimeters of error on the knot locations). Zero redundancy for cut rope (we accept this at all times when climbing with single ropes), but as much redundancy as you have extra pieces in. Works well with vertical cracks, poorly for horizontal (greatly effects extension and equalization). For this I would add the equalizing figure 8 with the rope. For the equalette, the master point direction can be changed by adjusting the cloves. Rick BlairFrom DenverJoined Oct 16, 2007295 points
 Mar 31, 2011 Also the clove hitch master point is a good one. Clove yourself to a piece, clove the rope to another piece, clove your master point in between the two pieces. You can slide the knots around to whatever length you need, but it is still redundant. You can add more cloves, but you can only equalize two of them unless you make things more complicated. DannyUncannyFrom VancouverJoined Aug 27, 201078 points
 Mar 31, 2011 Larry your Finite Element Analysis is garbage. A cordolete cannot support a moment as your model can. This doesn't even make for a moderately good approximation. Evan DeisFrom BoulderJoined May 15, 2009137 points
 Mar 31, 2011 I don't know how true this is, but i have heard the the sliding x does not equalize well if it is already weighted (e.g. a leader falls, loads, then pulls a piece on the fall, so the direction changes).any thoughts on this? I personally use webbing with full strength lops on either end. It is easy to equalize, static and I am more comfortable building my anchors with webbing then rope. (mtntools.com/cat/mt/webolette/... kinda gimmicky but so easy...) wlashgrahamJoined Oct 24, 20103 points
 Mar 31, 2011 Evan Deis wrote:Larry your Finite Element Analysis is garbage. A cordolete cannot support a moment as your model can. This doesn't even make for a moderately good approximation. That's a really helpful comment Evan. @Larry: However, you should consider some elasticity in your rigging. If you use the traditional 7mm perlon cord which has significant elasticity, the load will be much more distributed. Pascal RipocheFrom Pittsburgh PAJoined Oct 14, 2010201 points
 Mar 31, 2011 wlashgraham wrote:I don't know how true this is, but i have heard the the sliding x does not equalize well if it is already weighted (e.g. a leader falls, loads, then pulls a piece on the fall, so the direction changes).any thoughts on this? I personally use webbing with full strength lops on either end. It is easy to equalize, static and I am more comfortable building my anchors with webbing then rope. (mtntools.com/cat/mt/webolette/... kinda gimmicky but so easy...) I actually read the same thing about the sliding X but cant remember where. However, about the webolette, I see one minor difference between webollet and cordalette : slings are (mostly) not elastic while a cordalette made of nylon cord is pretty elastic which can distribute the load over several protection. Pascal RipocheFrom Pittsburgh PAJoined Oct 14, 2010201 points
 Mar 31, 2011 wlashgraham wrote:I don't know how true this is, but i have heard the the sliding x does not equalize well if it is already weighted (e.g. a leader falls, loads, then pulls a piece on the fall, so the direction changes).any thoughts on this? I personally use webbing with full strength lops on either end. It is easy to equalize, static and I am more comfortable building my anchors with webbing then rope. (mtntools.com/cat/mt/webolette/... kinda gimmicky but so easy...) Which is why you should tie one strand a bit shorter than the other. Anyways, the worse a system equalizes, the better it resists unexpected extensions. Think of it like the differential on a car. You can have a regular differential which distributes half of the power (load) to each wheel all the time, but if one wheel slips (protection fails) so that it can't apply that power, then you get a spin out where neither wheel is applying power, or in the climbing analogy, a free fall where both pieces become unweighted until you hit the full extension of the system. By contrast, a limited slip differential would be like a load sharing system that binds up and if one piece fails, then the other pieces don't immediately lose all of their load. Also, a regular cordalette would be the equivalent of no differential, just driving both wheels at the same speed off of one axle. This means that the wheels can't spin out, but you might put all of the load on one side DannyUncannyFrom VancouverJoined Aug 27, 201078 points
 Mar 31, 2011 Has anyone here ever blown a piece from their anchor or had any problems with either anchor scenario failing in any way that wasn't due to their own mistake? Ben WalburnJoined Jul 13, 2007684 points
 Mar 31, 2011 Ben, Nope, but I have a survivors bias. There have been anchor failures over the years, though thankfully few. Given that the anchor is truly the last line of defense against death, it is worth putting a little too much thought into it. John Long's writeup of the Equalette is pretty humble about the fact that there really have been VERY few anchor failures, and to my knowledge none attributed to the poor equalization of the Cordalette. However most anchors are NEVER stressed beyond body weight. How many WOULD fail if they actually had to handle a factor 2 leader fall? I'm guessing the number is larger than we'd like to admit to ourselves. So the pursuit of ever better anchors is worth rehashing endlessly. Given some of the "anchors" I've seen other parties make, I'd argue this subject should not be downplayed. If you feel solid with your anchor skills, feel content to move on. Edit: These guys won't be posting up to answer your question: cascadeclimbers.com/forum/ubbt... MoofFrom Portland, ORJoined Dec 11, 200715 points
 Mar 31, 2011 Moof, The link to the actual accident report at the end of the thread you posted from CC is dead. The thread ended with speculation about whether or not it was actually anchor failure but someone was citing rock and ice as a source that it was anchor failure. The thread also mentioned the fact that this curious belay that failed was set behind a flake. Not sure what to make of the story but I will say that no intricate amount of anchor rigging can make a flake stick to the wall any better. If that was indeed the cause for anchor failure. Just curious if you know more details? YarpJoined Jan 16, 20116 points
 Apr 1, 2011 In the Gaines/Long book they tested equalization of a cordalette and found it did a very POOR job in vertically spaced anchors. It did a better job in horizontal anchors but not ideal by any means. Any off axis loading throws the whole thing out the door. Hence their equalette work. mattmFrom TXJoined Jun 2, 20061,278 points
 Apr 1, 2011 Ya, I hear ya Moof. I'm not trying to be antagonistic here but rather simply posing a question that I'm curious about. I personally have never blown a piece in the 17 years I've been climbing and I am curious as to whether anyone else here has, how it happened and how it affected the anchor. Anyone?? Ben WalburnJoined Jul 13, 2007684 points

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