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i'm gumby dammit
Sport climber
da ow
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Topic Author's Original Post - Aug 9, 2013 - 02:56am PT
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I've only been climbing a year, but get out about 5 times a week and 2 or 3 of those days are with my daughters and much of the rest of the time is with people less experienced than me. The end result is that I get very little mentoring, much less than i need. As such I thought I would start taking pictures of anchors and otherwise documenting questionable decisions and then posting here to keep up with the learning process. It can probably help others as well.
Today's questionable anchor.
Decent bolts with locking biners > 20' of webbing tied with figure 8 > 48" sling doubled over webbing > 36" sling doubled over that > two quickdraws > rope. I also placed a cam in a crack as we were climbing on an arete and if the system moved left in the pic during a fall there would have been a swing bouncing through a chimney and then into a wall
my concerns
1. sling directly to webbing instead of connecting with 'biner. wasn't too concerned since there would be no movement of the slings through the webbing.
2. Figure 8 instead of water knot with webbing. Is that a big deal??
3. Should have done an overhand knot with the webbing in case one of the bolts went (just thought of this looking at the pic).
4. The two slings to extend to the edge provided no redundancy. This is my biggest concern since there were two pieces that could have failed catastrophically. Not sure how to compare this to simply elongating the 48" sling since there would then be twice as much force on it (or am I doing the wrong math?)
It occurs to me now I could have elongated the 48" and backed it up with the 36" and a doubled 24".
What's your take?
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Dr.Sprock
Boulder climber
I'm James Brown, Bi-atch!
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my take?
YOUR GONNA DIE!
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i'm gumby dammit
Sport climber
da ow
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Topic Author's Reply - Aug 9, 2013 - 03:22am PT
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not trolling at all.
this is my daughter hanging from it. i don't want to kill her (or anyone else)
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Clint Cummins
Trad climber
SF Bay area, CA
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1 & 2 don't matter
3 & 4 non-redundant, as you already figured out.
Also, since the cam sling does not clip into the main slings (just clips over them), it doesn't back up the bolts. It only prevents the main slings from moving left. It sounds like that was your goal, though.
Next time, bring more slings/webbing.
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i'm gumby dammit
Sport climber
da ow
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Topic Author's Reply - Aug 9, 2013 - 03:42am PT
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Thanks!
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HighDesertDJ
Trad climber
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If you find yourself setting up TR anchors like this a lot, you'd be wise to invest in a couple pieces of low-stretch rope that you can simply throw a figure-8 in and clip to a biner at the bolt and then another figure-8 with opposite/opposing biners (like you did) at the climbing rope. It's simple, durable, easily adjustable and much safer than what you have set up. Or you could just bring a couple of decent sized cordalettes.
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ruppell
climber
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I'm with Biotch on this one. Horrible set up for what's in the photo. Has to be a troll. If knot buy a book on anchors and read it. Twice.
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Edwardmw
climber
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I notice some problem's here, I will mention a few.
Check the attached images. I have circled some problem areas
In 1&2 the carabiners are resting sideways on the edge of the cliff, half way over the edge, they are not orientated properly, and strength is diminished.
3) Why not tie an overhand figure 8 instead of looping webbing through webbing?
4) This is simply a directional and does not reinforce your anchor
5) You use a single non locking carabiner with the gate facing the cliff. Hard to see for sure, but in the second image below, the one where you can see the top rope, looks like a single biner with the gate facing the cliff.
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justthemaid
climber
Jim Henson's Basement
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I'll bite.
I'd definitely just buy a long cordalette or piece of static rope for building anchors that need to extend off the edge. You should also invest in a few locking biners.
Things I'd improve: (top down)
Yes, water knot is the standard BTW. Ditch the fig 8.
The blue sling attached at the bolts has no limiter knots or half twist which means a break in the webbing or bolt failure (unlikely as it is) would mean catastrophic failure of everything else.
Generally I consider webbing on webbing bad but I'm assuming you were suffering from a biner shortage on this outing.
Purple slings. Problem: No redundancy. Anytime you loop a piece like that without a limiter knot any break in the webbing = anchor failure. It would have been better to extend the two full length and attach them with doubled/opposed/locking biners if you had them. If you are linking webbing to webbing to extend an anchor I prefer lockers or multiple opposed non-lockers since it's out of sight from the ground.
The cam could have been an active piece in the anchor and added needed redundancy had you clipped it directly to the biners. (Some people don't like biner on biner BTW) . In this case it looks like you actually could have extended the sling and clipped it directly to the climbing rope as a backup and directional (better).
The two quick-draws at the lip are funky but actually redundant. It would have been better to use longer slings over the lip.
Finally:I'd like to see at least one locking biner where the climbing rope attaches. The general rule is two opposed lockers or three opposed non lockers.
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neversummer
climber
30 mins. from suicide USA
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If you are TR-ing alot i would do like others suggest and get some 7mm cord and rig a "quad" ...bomber for two bolt anchors and it will accept some multi-directional pull....
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10b4me
Ice climber
Wishes-He-Was-In-Arizona
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I don't like nylon on nylon, myself.
I would extend the power point.
I have started carrying a length of static line for building anchors.
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kaholatingtong
Trad climber
Nevada City
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Quads are awesome for bolted TRin, you can read about them in CLimbing Anchors By long and Gaines, and even if not in a quad you should get a cordalette, IMO.
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rgold
Trad climber
Poughkeepsie, NY
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Asking for mentoring from a website has some inherent problems. You get a spectrum of information from people with varying degrees of experience and various perspectives on safety. Also, there usually isn't any grading of the responses, meaning that what some people would consider a small detail gets as much weight as what some would consider a major no-no. And pictures can be difficult to interpret, leading to advice that may not be relevant to the actual setup.
Since you don't want to kill yourself or those you are responsible for, you really need to spend a day or several days with an expert. I think that nowadays that means a certified guide.
Most of the potential problems have been identified. I'll try to offer some commentary.
(1) Carabiners resting on the edge or part way over the edge. This is a potentially fatal configuration that absolutely has to be avoided, so is certainly worth mentioning. But when I look at the picture I don't think it is happening in your anchor. Still, it is a critical concern. If bolts have been placed in such a way that carabiners clipped to them rest on an edge, then the bolter had no idea what they were doing, and I'd be worried about the integrity of the entire set-up, since you have direct evidence of incompetence.
(2) In the service of keeping your daughters alive and you from a lifetime of regret, I'm going to be harsh here. Certainly the worst feature of your set-up is the sling connection that results in total failure if one of the bolts fails. That can't be some kind of afterthought, as in, "gee, I just noticed in the photo..." That is a serious and, I'd say, irresponsible mistake. The fact that you completely undid all the redundancy intended by the two-bolt placement and then worried about directionals indicates mental processes that need major recalibration. No muli-piece anchor should ever fail totally if one part of it fails, that is about as basic an anchor-building tenet as there is. If you haven't learned that, and it doesn't seem that you have, then you shouldn't be building top-rope anchors until you get some more instruction.
A year ago, in one of the most horrific accidents I've encountered in more than a half-century of climbing, a young woman trying climbing for the very first time was killed when she leaned back on her top-rope and the entire anchor rigging fell down. No one knows exactly how that anchor was constructed, but you've set up an example that could produce an analogous result.
(3) Knots. I don't know what you mean by a figure-eight knot, it isn't a term used for knots joining two ends. The most likely guess is that you used a Flemish Bend, which is adequate but not standard. Although a water knot is standard, its use for slings intended for top-roping is not the best idea. Water knots in webbing subjected to repeated loading and unloading are subject to end creep, which is to say that the ends slowly move back into the knot. You have to make sure you have relatively long ends, and you have to check your slings every time you use them to make sure the knots are not in danger of untying because the ends have crept in. A far better, although uglier, knot to use is the double fisherman's bend. As an added bonus (of relatively little importance) it is a stronger knot than the ring bend. A potential drawback (of almost no consequence) is that you'll probably never be able to untie a double fisherman's after it has been loaded multiple times.
(4) Directionals. Good thinking but terrible execution. Don't ever place a piece and then not have it contribute to the load-bearing capacity of the anchor. In your case, a sling of appropriate length should have run from the directional cam to the power point.
(5) Carabiners. In a top rope anchor, it makes sense for every carabiner to be either a locker or a pair of non-lockers with gates opposed. It is a little hard for me to grade this one, considering that back in the day no one carried a bunch of lockers and all anchors, including complex big-wall ones, were constructed with ordinary biners. But top-rope anchors are unattended, and small unanticipated motions could open gates, weakening the system. As for the primary power point, I've certainly use a pair of opposed non-lockers and not worried about it, but opposed lockers or tripled non-lockers are a bit safer, especially if the power point contacts the rock.
(6) Lateral rope motions. This isn't always a problem, but if it is one there is a danger of cutting through the anchor rigging or the climbing rope if the system is sawing back and forth over an edge because of rope motions from the climber. This means that you have to come prepared to pad edges to protect rigging. In some cases, by far the best solution is to place a piece over the edge, on the main face, with the rigging set up so that the power point loads this piece and the rest of the anchor backs it up. The point is to prevent any back-and-forth sawing motions over the edge. Note that your directional fails to do this, since it leaves a portion of sling below the directional carabiner to rub back and forth as the powerpoint moves. This is one of the reasons why a direct sling from your directional to the power point would have been better.
(7) Gear. You don't seem to have enough. Probably a good length of static rope is the way to go for rigging top-rope anchors.
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WBraun
climber
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For top roping get a 30 foot piece of 8 or 9mm rope to extend anchors over a lip.
Forget all those extra slings and biners chained together.
One piece of rope instead of all those individual links chained together .....
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i'm gumby dammit
Sport climber
da ow
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Topic Author's Reply - Aug 9, 2013 - 12:19pm PT
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wow! lots of replies while i slept. thanks again. to answer some concerns.
edwardmw,
the biners at the bolts are fine, not resting on the side of a cliff, and they are orientated properly.
at the other end, there are two opposed biners. the rest of your stuff is correct.
cordalette is to be one of my next purchases.
i know nylon running through nylon is very bad, but have read that in static situations it is ok. someone mentioned girth hitches, there were none. my understanding is that knots in slings create weak points so i was trying to avoid that in this case.
point taken regarding the directional. i originally had the biner through the rope but was having a hard time envisioning what would happen if things started to creep away and the connections became separated from each other. then i thought of clipping it to one the dogbones on the draws and thought that could make things twist.
i do have an extra rope i've semi retired since it's been cut down to 50m. is dynamic ok, or does it have to be static as someone mentioned above?
and thanks, this is what i was looking for. even (or especialy) the harsh criticisms
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i'm gumby dammit
Sport climber
da ow
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Topic Author's Reply - Aug 9, 2013 - 12:24pm PT
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In fact using two bolts in this way is actually worse than using a single bolt, since it doubles the probability of failure due to a damaged/incorrectly placed bolt. isn't this 6 in one, half dozen in the other? half as much chance since the forces are split in half (or almost in this case) but twice as much since either could fail versus full weight on one bolt with a 50% chance that i chose the right one?
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HighDesertDJ
Trad climber
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A high stretch rope can work but you will often wind up with big TR falls and your anchor points a lot lower than you intended after the stretch. Just buy some low stretch off a spool at a climbing store. 2x 10 meter lengths will handle most situations but you can go longer if you want.
As for avoiding knots, that is a smart move in theory but in practice you aren't generating enough force on a top rope to have to worry about that. What that thinking lead you to do is thread your blue anchor webbing through your purple/white sling in such a way that it is creating the exact kind of nylon-nylon friction that you want to avoid. Additionally, you completely eliminated any redundancy in your anchor because if either bolt blows, biner fails, webbing breaks or knot unties on that blue webbing section your whole anchor fails.
All in all a fairly unsafe anchor. If I found my daughter TRing on it I would have words with its builder.
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Spider Savage
Mountain climber
The shaggy fringe of Los Angeles
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I understand the the Top-Rope Guide course is teaching guides to use a 100 ft of static 10.5 mm rope to set up all Top rope situations.
I followed this advice and have been enjoying fast and solid set-ups since I started doing this.
Simplicity.
As 10b4me mentioned, I avoid nylon on nylon connections. In my mind that is a weak point. I've not heard of pull tests done on these but it would be very interesting to see.
PS> Get yourself a better name and avatar for this site and become one of us.
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