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UpToTheOzone
Jun 10, 2012, 1:24 AM
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Just curious why using a single runner with a sliding X and limiter knots is used over two different slings with opposing biners. I know that not everything in climbing is redundant (ie: 1 rope, 1 belay device ) but it confuses me why one would make an anchor out of a single sling, instead of two slings. I'm also much more comfortable with two opposed draws /biners on separate slings than just having 1 locker on my anchor. I recently got an ATC Guide, and would love to start using it in the autoblocking configuration, but the one locker still does not comfort me. I realize that the system is closed and the limiters will prevent shock loading, but I feel it is much faster to place two draws (or slings) up than to use a single sliding X sling.
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surfstar
Jun 10, 2012, 2:34 AM
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I prefer a sliding X for TRs where the climber will wander and it will adjust a bit for equalization (yeah, not perfect due to friction, I know, but it still tensions both bolts better than two equal draws do), but really, either way is fine and safe. Figure out which you prefer and use it.
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vinnie83
Jun 10, 2012, 7:07 AM
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Are these two bolt anchors on the top of a single pitch climb that people will be toproping after you lead it or on a multipitch climb? How the anchor is being used and what you have available can affect how you set up an anchor. The majority of the time I'm doing single pitch stuff with bolted anchors I just use 2 different quickdraws/runners because like you said it is a fast and adequate anchor. So you are comfortable belaying someone on lead with one biner, clipping a piece of gear or bolt with one biner that could be the only thing keeping you from decking, but when it comes to belaying a second from above and have very little chance of cross loading a biner you are worried about the single biner failing?
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marc801
Jun 10, 2012, 7:09 PM
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UpToTheOzone wrote: Just curious why using a single runner with a sliding X and limiter knots is used over two different slings with opposing biners. I know that not everything in climbing is redundant (ie: 1 rope, 1 belay device ) but it confuses me why one would make an anchor out of a single sling, instead of two slings. I'm also much more comfortable with two opposed draws /biners on separate slings than just having 1 locker on my anchor. I recently got an ATC Guide, and would love to start using it in the autoblocking configuration, but the one locker still does not comfort me. I realize that the system is closed and the limiters will prevent shock loading, but I feel it is much faster to place two draws (or slings) up than to use a single sliding X sling. You have a basic but common misunderstanding of the meaning of "redundancy" in climbing.
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CurlyFries
Jun 11, 2012, 4:56 PM
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I use a sling equalette with limiter knots on the majority of my bolted toprope anchors. It is a very similar setup to the sliding X with limiter knots.
UpToTheOzone wrote: Just curious why using a single runner with a sliding X and limiter knots is used over two different slings with opposing biners. I know that not everything in climbing is redundant (ie: 1 rope, 1 belay device ) but it confuses me why one would make an anchor out of a single sling, instead of two slings. I think you are missing that the limiting knots essentially turn the sling into two slings. I also use two lockers instead of one.
UpToTheOzone wrote: I realize that the system is closed and the limiters will prevent shock loading, but I feel it is much faster to place two draws (or slings) up than to use a single sliding X sling. I usually prepare it before the climb and rack it to go with me. I have used two draws as an anchor and it really doesn't take much longer to set up. The sling is much more versatile and the lockers make me happy. Dave
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mattyp
Jun 11, 2012, 5:03 PM
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marc801 wrote: You have a basic but common misunderstanding of the meaning of "redundancy" in climbing. Care to elaborate?
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Rudmin
Jun 11, 2012, 6:11 PM
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mattyp wrote: marc801 wrote: You have a basic but common misunderstanding of the meaning of "redundancy" in climbing. Care to elaborate? A sliding x with limiting knots IS redundant.
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mattyp
Jun 11, 2012, 7:06 PM
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Thanks for making the point. The OP may have been scratching his/her head. You don't know what you don't know, right?
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patto
Jun 11, 2012, 8:00 PM
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Rudmin wrote: mattyp wrote: marc801 wrote: You have a basic but common misunderstanding of the meaning of "redundancy" in climbing. Care to elaborate? A sliding x with limiting knots IS redundant. No. It. Isn't. (Unless of course you comment was dismissing the sliding x with limiter knots as an effective anchor device )
(This post was edited by patto on Jun 11, 2012, 8:15 PM)
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shockabuku
Jun 11, 2012, 8:08 PM
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patto wrote: Rudmin wrote: mattyp wrote: marc801 wrote: You have a basic but common misunderstanding of the meaning of "redundancy" in climbing. Care to elaborate? A sliding x with limiting knots IS redundant. No. It. Isn't. (Unless of course you comment was dismissing the sliding x with limiter knots as an effective anchor device ) *Unless you are talking Another great discussion by the masters of the obscure.
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shimanilami
Jun 11, 2012, 8:11 PM
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UpToTheOzone wrote: I recently got an ATC Guide, and would love to start using it in the autoblocking configuration, but the one locker still does not comfort me. Do you use two lockers to belay currently? Whatever. One locker is plenty good for top-ropes or belays ... provided it's locked, of course.
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cracklover
Jun 11, 2012, 8:53 PM
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UpToTheOzone wrote: Just curious why using a single runner with a sliding X and limiter knots is used over two different slings with opposing biners. I know that not everything in climbing is redundant (ie: 1 rope, 1 belay device ) but it confuses me why one would make an anchor out of a single sling, instead of two slings. I'm also much more comfortable with two opposed draws /biners on separate slings than just having 1 locker on my anchor. I recently got an ATC Guide, and would love to start using it in the autoblocking configuration, but the one locker still does not comfort me. I realize that the system is closed and the limiters will prevent shock loading, but I feel it is much faster to place two draws (or slings) up than to use a single sliding X sling. Out of curiosity, why do you care? For a good two bolt anchor, you can use about a million configurations, and so long as the connection to the rope is okay, it doesn't matter one whit. You may as well be asking if chocolate or strawberry is better. GO
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shockabuku
Jun 11, 2012, 9:30 PM
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patto wrote: shockabuku wrote: Another great discussion by the masters of the obscure. The masters of the obscure? Are we here to discuss climbing or to discuss give an English lesson? Because if I was going to elaborate on my response I would have to start teaching English and the meaning of the word redundancy. Who knows, maybe that's the problem. Based on your responses (without the original context) you could be discussing anything. Even with the orignial context it's hard to tell what anyone is really getting at with the once sentence responses other than that you disagree.
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Derek_Doucet
Jun 11, 2012, 11:37 PM
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patto wrote: Rudmin wrote: mattyp wrote: marc801 wrote: You have a basic but common misunderstanding of the meaning of "redundancy" in climbing. Care to elaborate? A sliding x with limiting knots IS redundant. No. It. Isn't. (Unless of course you comment was dismissing the sliding x with limiter knots as an effective anchor device ) Patto, will you please elaborate on what you mean by this? In what sense is a 2-bolt anchor built with a sliding x with limiting knots not redundant?
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mattyp
Jun 11, 2012, 11:57 PM
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Derek_Doucet wrote: Patto, will you please elaborate on what you mean by this? In what sense is a 2-bolt anchor built with a sliding x with limiting knots not redundant? That's what I was thinking. Doesn't the knot somewhat create two legs in the anchor, i.e. one side failing doesn't mean the other side will fail like when you simply use a sliding X without a limiting knot?
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marc801
Jun 12, 2012, 12:16 AM
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cracklover wrote: You may as well be asking if chocolate or strawberry is better. Completely ignoring the exquisiteness of strawberries in/with chocolate. Nice going trad boy! Way to muddy the waters!
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patto
Jun 12, 2012, 2:56 AM
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Derek_Doucet wrote: Patto, will you please elaborate on what you mean by this? In what sense is a 2-bolt anchor built with a sliding x with limiting knots not redundant? The anchor is not redundant. Using a sliding x with limiting knots is not redundant. re·dun·dant (r-dndnt) adj. 1. Exceeding what is necessary or natural; superfluous. 2. Needlessly wordy or repetitive in expression: a student paper filled with redundant phrases. 3. Of or relating to linguistic redundancy. 4. Chiefly British Dismissed or laid off from work, as for being no longer needed. 5. Electronics Of or involving redundancy in electronic equipment. 6. Of or involving redundancy in the transmission of messages. The sliding x sling is not redundant. It is not unnecessary or superfluous. Without it there is no anchor. Things can only be considered redundant if there is no material change of the system from their removal.
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jt512
Jun 12, 2012, 3:11 AM
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patto wrote: Derek_Doucet wrote: Patto, will you please elaborate on what you mean by this? In what sense is a 2-bolt anchor built with a sliding x with limiting knots not redundant? The anchor is not redundant. Using a sliding x with limiting knots is not redundant. re·dun·dant (r-dndnt) adj. 1. Exceeding what is necessary or natural; superfluous. 2. Needlessly wordy or repetitive in expression: a student paper filled with redundant phrases. 3. Of or relating to linguistic redundancy. 4. Chiefly British Dismissed or laid off from work, as for being no longer needed. 5. Electronics Of or involving redundancy in electronic equipment. 6. Of or involving redundancy in the transmission of messages. The sliding x sling is not redundant. It is not unnecessary or superfluous. Without it there is no anchor. Things can only be considered redundant if there is no material change of the system from their removal. Hilarious.
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shockabuku
Jun 12, 2012, 1:23 PM
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I generally consider redundancy to be applicable to the safety factors (load bearing capacity) not the particulars of the construction.
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Derek_Doucet
Jun 12, 2012, 2:21 PM
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patto wrote: Derek_Doucet wrote: Patto, will you please elaborate on what you mean by this? In what sense is a 2-bolt anchor built with a sliding x with limiting knots not redundant? The anchor is not redundant. Using a sliding x with limiting knots is not redundant. re·dun·dant (r-dndnt) adj. 1. Exceeding what is necessary or natural; superfluous. 2. Needlessly wordy or repetitive in expression: a student paper filled with redundant phrases. 3. Of or relating to linguistic redundancy. 4. Chiefly British Dismissed or laid off from work, as for being no longer needed. 5. Electronics Of or involving redundancy in electronic equipment. 6. Of or involving redundancy in the transmission of messages. The sliding x sling is not redundant. It is not unnecessary or superfluous. Without it there is no anchor. Things can only be considered redundant if there is no material change of the system from their removal. Pedantic adj. Marked by a narrow, often tiresome focus on or display of learning and especially its trivial aspects *sigh*
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olderic
Jun 12, 2012, 2:24 PM
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jt512 wrote: patto wrote: Derek_Doucet wrote: Patto, will you please elaborate on what you mean by this? In what sense is a 2-bolt anchor built with a sliding x with limiting knots not redundant? The anchor is not redundant. Using a sliding x with limiting knots is not redundant. re·dun·dant (r-dndnt) adj. 1. Exceeding what is necessary or natural; superfluous. 2. Needlessly wordy or repetitive in expression: a student paper filled with redundant phrases. 3. Of or relating to linguistic redundancy. 4. Chiefly British Dismissed or laid off from work, as for being no longer needed. 5. Electronics Of or involving redundancy in electronic equipment. 6. Of or involving redundancy in the transmission of messages. The sliding x sling is not redundant. It is not unnecessary or superfluous. Without it there is no anchor. Things can only be considered redundant if there is no material change of the system from their removal. Hilarious. Patto? The sliding-X? The definition? Chocolate? Your statement is ambiguous. No it isn't. Yes it is. Ah - RC.com - the highest noise/signal ratio ever accomplished by mankind.
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marc801
Jun 12, 2012, 2:49 PM
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olderic wrote: Ah - RC.com - the highest noise/signal ratio ever accomplished by mankind. Don't forget the final days of rec.climbing and rec.alpineskiing - those are both pretty high bars to clear.
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olderic
Jun 12, 2012, 2:51 PM
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marc801 wrote: olderic wrote: Ah - RC.com - the highest noise/signal ratio ever accomplished by mankind. Don't forget the final days of rec.climbing and rec.alpineskiing - those are both pretty high bars to clear. Ah the good old days. I do remember.
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marc801
Jun 12, 2012, 2:51 PM
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patto wrote: Derek_Doucet wrote: Patto, will you please elaborate on what you mean by this? In what sense is a 2-bolt anchor built with a sliding x with limiting knots not redundant? The anchor is not redundant. Using a sliding x with limiting knots is not redundant. re·dun·dant (r-dndnt) adj. 1. Exceeding what is necessary or natural; superfluous. 2. Needlessly wordy or repetitive in expression: a student paper filled with redundant phrases. 3. Of or relating to linguistic redundancy. 4. Chiefly British Dismissed or laid off from work, as for being no longer needed. 5. Electronics Of or involving redundancy in electronic equipment. 6. Of or involving redundancy in the transmission of messages. The sliding x sling is not redundant. It is not unnecessary or superfluous. Without it there is no anchor. Things can only be considered redundant if there is no material change of the system from their removal. Anyone with half a brain and has been climbing longer than a few days knows that none of these definitions apply to how the term is used in the technical climbing domain.
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JimTitt
Jun 12, 2012, 3:04 PM
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shockabuku wrote: I generally consider redundancy to be applicable to the safety factors (load bearing capacity) not the particulars of the construction. In engineering (and many other fields) safety factor and redundancy are different things and have to be evaluated differently. For example the commercial aircraft you fly in uses safety factors for the airframe but redundancy for the propulsion system and the pilot. A useful paper on the logic behind the two systems is http://www.umowlai.com.au/uploads/Cliffhanger.pdf which is reasonably understandable. A sliding X with limiters is partly redundant (if the sling fails between the limiter knots you die), two draws are completely redundant. Two draws is considerably stronger and therefore has a higher safety factor. I´d prefer the system with a higher safety factor and complete redundancy myself!
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Derek_Doucet
Jun 12, 2012, 3:21 PM
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JimTitt wrote: shockabuku wrote: I generally consider redundancy to be applicable to the safety factors (load bearing capacity) not the particulars of the construction. In engineering (and many other fields) safety factor and redundancy are different things and have to be evaluated differently. For example the commercial aircraft you fly in uses safety factors for the airframe but redundancy for the propulsion system and the pilot. A useful paper on the logic behind the two systems is http://www.umowlai.com.au/uploads/Cliffhanger.pdf which is reasonably understandable. A sliding X with limiters is partly redundant (if the sling fails between the limiter knots you die), two draws are completely redundant. Two draws is considerably stronger and therefore has a higher safety factor. I´d prefer the system with a higher safety factor and complete redundancy myself! Hi Jim, I look at this from a slightly different perspective: For a 2-bolt anchor constructed with the sliding x and limiting knots to fail catastrophically, a minimum of 2 components of the system must fail: Both strands of the sling between the limiting knots, or one strand of the sling between the limiting knots and one of the bolts. To me, this satisfies the principle of redundancy as it is commonly understood in climbing vernacular, if not the engineering world. That said, I certainly agree that for a top rope anchor on which the anticipated direction of loading is predictable and consistent, there is no advantage to such a system over 2 QDs. Cheers, Derek
(This post was edited by Derek_Doucet on Jun 12, 2012, 3:22 PM)
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mattyp
Jun 12, 2012, 3:46 PM
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marc801 wrote: You have a basic but common misunderstanding of the meaning of "redundancy" in climbing.
marc801 wrote: Anyone with half a brain and has been climbing longer than a few days knows that none of these definitions apply to how the term is used in the technical climbing domain. What did you mean in your initial post? What is the OP's basic and common misunderstanding?
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marc801
Jun 12, 2012, 4:50 PM
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mattyp wrote: marc801 wrote: You have a basic but common misunderstanding of the meaning of "redundancy" in climbing. marc801 wrote: Anyone with half a brain and has been climbing longer than a few days knows that none of these definitions apply to how the term is used in the technical climbing domain. What did you mean in your initial post? What is the OP's basic and common misunderstanding? That *absolutely everything* in the system needs to be 100% redundant and that this is interpreted as an iron-clad, unchangeable rule in *all* situations. Couple that with the dictionary meaning of redundant and, as we've seen in other threads, the end result could well be more dangerous (or more difficult to assess) than a system that has a less religious adherence to "redundancy".
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bearbreeder
Jun 12, 2012, 5:22 PM
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what in the world is everybody arguing about again? .... TR anchors on 2 bolts ???? its amazing how RCers go on and on about TR anchors ... in the real world people just go out and climb ...
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cracklover
Jun 12, 2012, 5:28 PM
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marc801 wrote: olderic wrote: Ah - RC.com - the highest noise/signal ratio ever accomplished by mankind. Don't forget the final days of rec.climbing and rec.alpineskiing - those are both pretty high bars to clear. Not sure about if you're referring to the late days, when the wreck was mostly flame wars, or the very late days, when it was nothing but spambots/loonies/conspiracy nuts? At least the former was somewhat entertaining. GO
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mattyp
Jun 12, 2012, 5:50 PM
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Thanks for clearing that up. I was worried I had some misunderstandings since your initial post wasn't clear to me.
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cracklover
Jun 12, 2012, 5:51 PM
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One of the things I wish the anchor books would do is to help new climbers begin to think more critically and constructively about safety issues. For example, every book has some version of the SRENE acronym for anchor building. But it is always presented as a gold standard. At best, the books admit that it is a standard that is never fully attainable, but where does that leave the reader? Knowing that there are tradeoffs to be made, but having no clue about when to err in which direction with those tradeoffs. A simple example: Option 1 - two independent slings, or option 2 - one sling with a sliding-x Which is better? Well if the situation is a couple of pretty decent RPs protecting a difficult move in the middle of a pitch, it should be understood that the better "equalization" (read "shared load") is a higher priority, so the climber should prefer option 2. However in the case of a two bolt toprope anchor in which the material will run over an edge, and cannot be constantly in view, it should be understood that redundancy is a higher priority, so option 1 is superior. This is just a simple example. What I wish the books would do is to help explain the decision-making process that goes into coming up with a solution to this example. There are basic principles involved, and they could be laid out in a way that helps new climbers begin to develop good habits of thought that will lead them in the right direction each time a new problem arises. GO
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patto
Jun 12, 2012, 6:03 PM
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marc801 wrote: You {UpToTheOzon} have a basic but common misunderstanding of the meaning of "redundancy" in climbing. Ok, so even if misunderstandings are common it doesn't make it correct. Good. We can agree on something.
marc801 wrote: Anyone with half a brain and has been climbing longer than a few days knows that none of these definitions apply to how the term is used in the technical climbing domain. Oh, but if your misunderstanding is pointed out then suddenly the other person is wrong! Just because redundancy is not understood by you and your friends doesn't mean the meaning suddenly changes. In fact as is quite clear in this thread, and you yourself pointed out, it is commonly misunderstood. Most things in climbing AREN'T redundant. Get the notion of everything being redundant out of your head. Gear such are ropes, harnesses, anchor systems are generally not redundant. You generally only have 1 of them. But that is fine because equipment failure is extremely rare. Your belayer is not redundant. What is less rare is and needs to be catered for is trad protection failure. We build anchors with 3 pieces when in reality 1 normally will do. This is to ensure redundancy. Before a crux I may place two pieces, again this is for redundancy.
cracklover wrote: One of the things I wish the anchor books would do is to help new climbers begin to think more critically and constructively about safety issues...... Exactly, I totally agree with the example given. And the lack of understanding about all this has led to the confusion displayed in this thread. Most of the time redundancy is the goal. (which really requires little or no extension to be seamlessly redundant). But in your RP example equalisation is a sensible goal. The only times I have used sliding x configurations is in such situations. Where I climb (trad) the sliding x is rarely used.
(This post was edited by patto on Jun 12, 2012, 6:13 PM)
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JimTitt
Jun 12, 2012, 6:05 PM
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This is something that is causing me a few problems in an article I´m (very slowly) writing, working out how one recognises the optimum strategy or at least avoids the worst one. The problem is mostly the technical aspects (equalisation, shock loading, load shift and so on) aren´t as clear cut as they could be so it´s hard to really say x is better than y, there are so many qualifiers added that it all ends up a bit muddled. I´m tending towards strategies that perform at say 90% all the time instead of 100% some of the time combined with simple systems that have proved reliable over the years, the trouble being this all sounds too basic for the modern generation who want to learn from books and videos and have trouble with the concept of just getting loads of gear and tying it all together somehow. I´ll just have to dress it all up with some cool sounding phrases so it´s trendy I guess!
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marc801
Jun 12, 2012, 6:19 PM
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JimTitt wrote: This is something that is causing me a few problems in an article I´m (very slowly) writing, working out how one recognises the optimum strategy or at least avoids the worst one. The problem is mostly the technical aspects (equalisation, shock loading, load shift and so on) aren´t as clear cut as they could be so it´s hard to really say x is better than y, there are so many qualifiers added that it all ends up a bit muddled. I´m tending towards strategies that perform at say 90% all the time instead of 100% some of the time combined with simple systems that have proved reliable over the years, the trouble being this all sounds too basic for the modern generation who want to learn from books and videos and have trouble with the concept of just getting loads of gear and tying it all together somehow. I´ll just have to dress it all up with some cool sounding phrases so it´s trendy I guess! If you didn't like word problems in math class, you probably shouldn't be building anchors! Anchor building isn't a set of rules you learn by rote - it's an applied engineering problem. Knowledge of physics is helpful.
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Rudmin
Jun 12, 2012, 6:35 PM
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JimTitt wrote: A sliding X with limiters is partly redundant ( if the sling fails between the limiter knots you die), two draws are completely redundant. Two draws is considerably stronger and therefore has a higher safety factor. I´d prefer the system with a higher safety factor and complete redundancy myself! if the sling fails twice
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cracklover
Jun 12, 2012, 6:47 PM
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JimTitt wrote: This is something that is causing me a few problems in an article I´m (very slowly) writing, working out how one recognises the optimum strategy or at least avoids the worst one. The following may or may not be helpful in the specific cases you deal with in your article, but I've found it to be helpful to me in explaining things to other climbers: 1 - Categorize the situation first by identifying the most dangerous aspects to it. And then 2 - Look for a solution to the situation that puts the highest priority on mitigating the most serious dangers. For example, in the dual case I took before: In the first case, the most serious danger for the lead climber with the two RP placements is that both of them will fail, and she will take a long and dangerous fall. And the best way to mitigate that risk is by equalizing those placements. Then, in the second case, the most serious danger for the toproper is that a line running over the edge may get worn through or cut on an unnoticed sharp crystal, dropping the climber until the other line catches her. And the best way to mitigate that risk is to have two independent lines running over the edge, with a static knot tied at the power-point. Does that make sense? Does it help at all? GO
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bearbreeder
Jun 12, 2012, 6:48 PM
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thats weird ... i havent come across any 2 bolts anchors that you couldnt just use a sling and tie off with a fig 8 yet, with padding if needed ... i wasnt aware that i needed to be a math expert to build an 2 bolt TR anchor
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bearbreeder
Jun 12, 2012, 8:11 PM
Post #42 of 49
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Registered: Feb 2, 2009
Posts: 1960
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were talking about 2 bolt TR anchors here ... not about some sketch micronut, camhook anchor ... beginners (and if they have to ask about TR bolt anchors, they are beginners) should just really KISS if i had a dollar every time some person comes up and argues about TR bolt anchoring on RC, or sadly the crag ... often something about quads being the best, sliding Xs being unsafe, or some either weird shiet ... i could afford another set of dragons ... if youre arguing about TR bolt anchors, yr either on RC ... or yr very very new ...
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cracklover
Jun 12, 2012, 8:46 PM
Post #43 of 49
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Registered: Nov 14, 2002
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You're missing my point. Of course there is a spectrum of complexity, with bolted TR anchors being on one end, and serious injury alpine rescue situations on the other. No-one is claiming that both require the same set of skills. What I am claiming is that at every level of complexity, even the most simple one, having a skill set that's just a little bit wider than what is typically required, and then having the awareness of what to keep an eye out for to mean that things don't look quite right, and the good sense to know what to do about it when that happens, is absolutely crucial. GO
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shockabuku
Jun 12, 2012, 9:01 PM
Post #44 of 49
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cracklover wrote: JimTitt wrote: This is something that is causing me a few problems in an article I´m (very slowly) writing, working out how one recognises the optimum strategy or at least avoids the worst one. The following may or may not be helpful in the specific cases you deal with in your article, but I've found it to be helpful to me in explaining things to other climbers: 1 - Categorize the situation first by identifying the most dangerous aspects to it. And then 2 - Look for a solution to the situation that puts the highest priority on mitigating the most serious dangers. For example, in the dual case I took before: In the first case, the most serious danger for the lead climber with the two RP placements is that both of them will fail, and she will take a long and dangerous fall. And the best way to mitigate that risk is by equalizing those placements. Then, in the second case, the most serious danger for the toproper is that a line running over the edge may get worn through or cut on an unnoticed sharp crystal, dropping the climber until the other line catches her. And the best way to mitigate that risk is to have two independent lines running over the edge, with a static knot tied at the power-point. Does that make sense? Does it help at all? GO I think this falls into general decision making processes which can, to some degree, be taught but in order to do it well you need a broad base of understanding of the subject matter you're dealing with. For instance, one of the early steps of the military decision making process is to try to understand your enemy. Staffs generally try to identify the most likely, as well as the most dangerous, enemy course of action and, when developing friendly courses of action endeavor to effectively counter both of these potential outcomes in their solution. However, without a good base of experience to apply to the situation you're likely to have some big holes in your plan. The most effective method to train decision making that I have seen is through example and "hands on" experience with few shortcuts (especially for those who don't learn well from others' mistakes).
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bearbreeder
Jun 12, 2012, 9:06 PM
Post #45 of 49
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common sense and experience ... you get that with a straight head and going out climbing as much as you can ... there are plenty of people i know who climb a minimal amount of time outdoors and preach to others what to do ... as i keep on telling people ... the only way to be "safe" is to go out and practice it over and over again safely and get experienced enough to think for yourself and solve problems ... many think that just because they took a basic course, or something are members of some alpine club that they are "safe", even if they rarely go out and practice their skills some get quite upset when i nicely tell em that they shouldnt be telling others what to do if they dont get out and climb very often ... i once remember some people arguing about how they would do a fancy rescue and how they knew all the appropriate skills and would never climb with anyone who didnt ... i pointed out simply that theoretical situations arent what kill you, its the fcuk ups here and now that do, some werent impressed ... one of the arguers later rapped off the ends of his rope ... KISS but since we digress as usual on RC ... back to the main theme ... KISS ... most beginners wont know or need to now anything more than the basics for setting up a TR bolt anchor ... if they want more its up to them ... but a little knowledge is a dangerous thing as witnessed by all these TR anchor threads on RC
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shockabuku
Jun 12, 2012, 9:10 PM
Post #46 of 49
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Registered: May 20, 2006
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JimTitt wrote: shockabuku wrote: I generally consider redundancy to be applicable to the safety factors (load bearing capacity) not the particulars of the construction. In engineering (and many other fields) safety factor and redundancy are different things and have to be evaluated differently. For example the commercial aircraft you fly in uses safety factors for the airframe but redundancy for the propulsion system and the pilot. A useful paper on the logic behind the two systems is http://www.umowlai.com.au/uploads/Cliffhanger.pdf which is reasonably understandable. A sliding X with limiters is partly redundant (if the sling fails between the limiter knots you die), two draws are completely redundant. Two draws is considerably stronger and therefore has a higher safety factor. I´d prefer the system with a higher safety factor and complete redundancy myself! It's not clear to me that two draws are redundant and that the sliding X with limiter knots is not. The sliding x has two strands in the center, both of which must fail (or along with something else) for catastrophic failure. While I would concede that the likelihood of both strands of the sliding x failing at the same time are probably significantly more likely than both biners in a two draw situation failing simultaneously, I think both have some probability and therefore are not categorically different; only different in their likelihood. I can understand the difference between safety factors and redundancy but it seems that some things (i.e. airframes, harnesses, etc.) are not feasibly made redundant so other safety measures are taken in their case. In the end, I'd rather have two draws on a (straight forward) two bolt anchor.
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JimTitt
Jun 12, 2012, 9:31 PM
Post #47 of 49
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shockabuku wrote: JimTitt wrote: shockabuku wrote: I generally consider redundancy to be applicable to the safety factors (load bearing capacity) not the particulars of the construction. In engineering (and many other fields) safety factor and redundancy are different things and have to be evaluated differently. For example the commercial aircraft you fly in uses safety factors for the airframe but redundancy for the propulsion system and the pilot. A useful paper on the logic behind the two systems is http://www.umowlai.com.au/uploads/Cliffhanger.pdf which is reasonably understandable. A sliding X with limiters is partly redundant (if the sling fails between the limiter knots you die), two draws are completely redundant. Two draws is considerably stronger and therefore has a higher safety factor. I´d prefer the system with a higher safety factor and complete redundancy myself! It's not clear to me that two draws are redundant and that the sliding X with limiter knots is not. The sliding x has two strands in the center, both of which must fail (or along with something else) for catastrophic failure. While I would concede that the likelihood of both strands of the sliding x failing at the same time are probably significantly more likely than both biners in a two draw situation failing simultaneously, I think both have some probability and therefore are not categorically different; only different in their likelihood. I can understand the difference between safety factors and redundancy but it seems that some things (i.e. airframes, harnesses, etc.) are not feasibly made redundant so other safety measures are taken in their case. In the end, I'd rather have two draws on a (straight forward) two bolt anchor. However the sliding X sling is still only one component subject to a production failure, chemical damage, UV or a rock landing on it, the chances that this occurs with two draws is enormously lower especially if you used draws from different manufacturers and of different ages and materials. Draws all the way!
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cracklover
Jun 13, 2012, 6:12 PM
Post #48 of 49
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Registered: Nov 14, 2002
Posts: 10162
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shockabuku wrote: cracklover wrote: JimTitt wrote: This is something that is causing me a few problems in an article I´m (very slowly) writing, working out how one recognises the optimum strategy or at least avoids the worst one. The following may or may not be helpful in the specific cases you deal with in your article, but I've found it to be helpful to me in explaining things to other climbers: 1 - Categorize the situation first by identifying the most dangerous aspects to it. And then 2 - Look for a solution to the situation that puts the highest priority on mitigating the most serious dangers. For example, in the dual case I took before: In the first case, the most serious danger for the lead climber with the two RP placements is that both of them will fail, and she will take a long and dangerous fall. And the best way to mitigate that risk is by equalizing those placements. Then, in the second case, the most serious danger for the toproper is that a line running over the edge may get worn through or cut on an unnoticed sharp crystal, dropping the climber until the other line catches her. And the best way to mitigate that risk is to have two independent lines running over the edge, with a static knot tied at the power-point. Does that make sense? Does it help at all? GO I think this falls into general decision making processes which can, to some degree, be taught but in order to do it well you need a broad base of understanding of the subject matter you're dealing with. For instance, one of the early steps of the military decision making process is to try to understand your enemy. Staffs generally try to identify the most likely, as well as the most dangerous, enemy course of action and, when developing friendly courses of action endeavor to effectively counter both of these potential outcomes in their solution. However, without a good base of experience to apply to the situation you're likely to have some big holes in your plan. Absolutely. But in war, you have no choice but to deal with the situation as it is. One of the things I like most about climbing is that you get to choose your adventure. You put yourself in a situation in which you feel competent, but stretched, just to the right degree. So I can make plans for, say, the Diamond, or the Nose, while someone else can make plans for, say, a crag where they need to build their own anchors for toproping. (Which was me, not so many years ago). In each case you plan around an objective for which you're pretty sure you have both the skills, and the level of experience to know you will either succeed, or fail safely.
In reply to: The most effective method to train decision making that I have seen is through example and "hands on" experience with few shortcuts (especially for those who don't learn well from others' mistakes). Sure, but I think you can go a long way by getting the climber's head in the right place to start with - with the focus on the right things. Which is exactly what how-to books are for. GO
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cracklover
Jun 13, 2012, 6:22 PM
Post #49 of 49
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Registered: Nov 14, 2002
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OK, why not, I'll weigh in on the draws versus sliding-x thing. For a straightforward two-bolt anchor, as you'd see at the top of a sport climb, I'd go with two draws. The logic: I see both as functionally equivalent in both strength and redundancy. And when you have a choice of two functionally equivalent options, I'd always go with the one that is simpler, quicker to set up and take down, easier to check, and uses less gear. The crossed sling uses less gear, but is inferior in every other way. But, really, like I said before, it doesn't matter a bit. GO
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