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Alpine draws with rubber retainer AND knot

ebmudder · · Bronx, NY · Joined Jul 2011 · Points: 55

Healyje and 20kN...both of you referred to "moderate" use of the gear, but that probably means something different to you than me. Can you roughly characterize how many days a year "moderate use" represents? You might think 100 days/yr is moderate but sadly that might represent 3-4 yrs of use for me!

And it bears repeating that any empirical data on sling durability is only truly useful to the specific person reporting it, because it doesn't take into account storage location, exposure to sunlight, typical wear/usage, climbing environment conditions, type of rock, type and condition of biners on the alpine draw and probably many more factors that would dramatically affect the strength of the sling over time. 

Similarly, manufacturer recommendations can't take these factors into account and are likely to be extremely conservative at best, for both liability and business reasons. For example I bought a "new" tricam from an online vendor a few years ago, and the date code pegged it at being 6 yrs old. When I asked Camp cust. svc. if I should follow their sling-life recommendations based on that date, they told me that if it was brand new and, as was likely, been stored in a warehouse for that duration, I could _probably_ start the clock when I started using it, and not worry about the manufacture date...of course they encouraged me to use the usual care in examining it after each use for any signs of wear. They also said that their recommendation would be valid for "new" gear up to 10 yrs, old but not beyond that. This was for a nylon sling, btw, not Dyneema.

ebmudder · · Bronx, NY · Joined Jul 2011 · Points: 55
J. Albers wrote:

Thread drift for sure, but glad you shared. My first guess would have been rodents. In an area along Sonora Pass with 400-500 foot cliffs I have seen all kinds of sling and rope failures that looked similar on fixed lines etc. Pretty much anything that isn't fixed taught away from the rock gets chewed in my experience (and even then sometimes those little @-holes will scurry out from the bolt onto the rope and chew). I friend of mine almost ate it when developing in the Yos backcountry when they left a fixed line overnight, jugged in the morning only to find a 90% cut sling similar to yours due to rodents. Scary stuff. 

That said, your sling clearly did not fail because of age, which is the crux of the argument on this thread. With that in mind, does anyone here on MP think that we could get something together where the community gathered a mess of dyneema slings and sent them off for testing? This may be a total moon shot (and a ill-advised idea), however my thinking is that one person sending a few slings isn't super meaningful, but collecting 100+ slings from different users may provide some level of information. Thoughts?

It would provide a larger sample, but would still be meaningless. If people are concerned they should replicate Healyje's test with their own gear...this will give them the most accurate results for strength loss under _their_ use conditions. 

And using Healyje's test, all you could know is the relative loss of strength in slings from that manufacturing _batch_ alone. It would be nice to have absolute faith that the 8mm dyneema sling you bought 4 yrs ago is identical to the one you buy today, but that may not be a reasonable assumption either.

J. Albers · · Colorado · Joined Jul 2008 · Points: 1,926
ebmudder wrote:

It would provide a larger sample, but would still be meaningless. 

You are mistaken. The larger sample is literally the only meaningful to test sling strength. Why? Because as you rightfully pointed out, there are countless confounding factors when testing gear from any given individual. And controlling for these confounders would be practically impossible. Thus the only way to get a remotely meaningful result is to increase the sample size to the point that all of those factors "average out", leaving what is hopefully a mean signal of degradation under "general use" conditions. Is 100 slings enough? Of course not. But every order of magnitude larger the sample, the more meaningful the result will be. 

Greg D · · Here · Joined Apr 2006 · Points: 883

Back to the OP

If none of the other reasons prevent you from doing this, then this might be the best reason:

I tried this years ago (without the knot).  It made the sling a bit more cumbersome and less efficient to use despite hoping for the opposite.  Try it yourself for a few days.  Forget the knot since it is really easy to prevent the accidental unclipping shown in the DMM video.  Unlike in the dog bone rubber keepers, the o-ring on a sling is super easy to inspect when you clip the rope to the biner.  I used them for about 5 days of climbing and realized it was not an improvement.  

S. Neoh · · Unknown Hometown · Joined Oct 2009 · Points: 35
Mikey Schaefer wrote:

This is is obviously a thread drift but and I'd say totally unrelated to the original questions posed.  But I figure people still might find it interesting.

What I learnt in the end was to never rely solely on a non supervised sling.  Always clip the rope directly into the anchor like I'd thankfully done.  Since this incident I've actually stopped using slings at anchors while fixing.  I now just use butterfly knots to equalize and attach the rope directly to the bolts taking out a possible point of failure.

Sorry about the drift but thanks for all the info.  Glad you escaped injury in spite of the break.

And thanks for sharing sage advice.

ebmudder · · Bronx, NY · Joined Jul 2011 · Points: 55
J. Albers wrote:

You are mistaken. The larger sample is literally the only meaningful to test sling strength. Why? Because as you rightfully pointed out, there are countless confounding factors when testing gear from any given individual. And controlling for these confounders would be practically impossible. Thus the only way to get a remotely meaningful result is to increase the sample size to the point that all of those factors "average out", leaving what is hopefully a mean signal of degradation under "general use" conditions. Is 100 slings enough? Of course not. But every order of magnitude larger the sample, the more meaningful the result will be. 

I would agree if the sample was perfectly randomized for every possible condition, exposure and usage type, and your test was in fact several orders of magnitude larger. 

Dan Africk · · Brooklyn, New York · Joined May 2014 · Points: 275
Larry S wrote:

If you feel you must fix the biner one one end, then consider using a Rabbit Runner rather than an open sling.

I've tried this (using bluewater Titan rabbit runners), and would recommend against it. It seemed like a good idea, but I found that the stiff sewn portion of the loop would get stuck in the carabiner in funky ways and be more likely to unclip than any other configuration.

Rabbit runners have their uses (I carry a 12' one as a backup anchor-building material, for extending really far away anchor placements, and have used it for an emergency hauling system [works great due to low stretch]). But this isn't a good use in my experience.

Healyje · · PDX · Joined Jan 2006 · Points: 422
ebmudder wrote:

Healyje and 20kN...both of you referred to "moderate" use of the gear, but that probably means something different to you than me. Can you roughly characterize how many days a year "moderate use" represents? 

I live in the PNW so we have a relatively short season. "Moderate" for me means somewhere between 5-10 pitches once or twice a week from roughly mid-April thru mid-October. Roughly 27 weeks more or less. Call it 10 pitches / week so very roughly 270-300 pitches / year - could be 25% more or less depending on the weather and my client workload in any given year. 

ebmudder wrote:

And using Healyje's test, all you could know is the relative loss of strength in slings from that manufacturing _batch_ alone. It would be nice to have absolute faith that the 8mm dyneema sling you bought 4 yrs ago is identical to the one you buy today, but that may not be a reasonable assumption either.

Mammut no doubt has some exacting quality systems in place such that even though material is sourced in batches, both batch testing on the front end and destructive testing on the backend along with ISO9001 process rules in between makes it highly unlikely there are significant batch-to-batch performance differences in any product that makes it out to distribution.

Overall I'd say you guys are way over-thinking it - real slings, real rack, consistent decline in strength in moderate year-over-year use. All the quibbling would probably amount to an under 10% variance in the results so you're talking 9kn instead of 8kn. Still means you should retire them sooner than later.

Craig Childre · · Lubbock, TX · Joined Aug 2006 · Points: 4,860
Boissal wrote:

Not withstanding the fact that the rope end biner isn't going anywhere because of the knot + rubber retainer (which both on the rope end), both biners appear to be clipped to the sling in a perfect illustration of the triple method. Nothing is flying anywhere in this picture unless the silver biner is manually removed from the sling and thrown off the route.

A simple mistake looking at that picture... the sling bands together to looks like one strand... and the way it threads tricks the eye, thought it was doubled.  Should have known better... after no one said anything on the first page ;)

Dan Africk · · Brooklyn, New York · Joined May 2014 · Points: 275

- If you use DMM Revolver carabiners, there IS a good reason for doing this: It keeps the pulley in the useful orientation. I carry two alpine draws in this configuration.

I'm sure I'll get flamed for this being unnecessary, the gear being expensive and heavy and over-complicated, etc.. But I've found these very useful in reducing rope drag, especially in critical placements (often below a roof), where using a double-length draw instead could result in a longer and more dangerous fall, or interfere with the piece below it.

- However, there is a better (imo) way to do this, which also prevents the possibility of a 'death draw', but causes little to no decrease in sling strength due to knots: Wrap the sling around the biner an extra time (a 'round turn' in nautical / knot terminology), and then use a rubber O-ring rather than a keeper to secure it. Just twist the O-ring once before it goes around the sling, then once after (see pics below). If you can figure out how to do this with a standard rubber keeper, that's fine as well, but I haven't been able to. I use these 36mm silicone O-rings: smile.amazon.com/dp/B00AH8D8E0  (the 36mm work well for me, but the 32mm might make a tighter fit. Haven't tried those though.)

       

LIke anything else, there are tradeoffs to this method. I'm used to these, so they require almost no additional effort or time to deploy these (perhaps a fraction of a second), and if anything they are easier for me to clean and stay neater on my rack. But sometimes new partners do find them annoying or more difficult to deal with. (My attitude is, tough shit- if I'm leading, they can deal with up to two of the draws being slightly more confusing. When I'm following, they can place absolutely any gear in any way their heart desires, and I will clean it efficiently and neatly and without complaint. If it's that hard, learn to get better at cleaning.. Same goes with tricams, but that's another thread..)

MP · · Unknown Hometown · Joined Sep 2013 · Points: 2
Mikey Schaefer wrote:

This is is obviously a thread drift but and I'd say totally unrelated to the original questions posed.  But I figure people still might find it interesting.

During my first ascent of Father Time on Middle Cathedral I had fixed ropes to near the top of the cliff.  The below image is from the anchor on top of pitch 18.  This rope/sling/anchor had been in place for a couple weeks before it was found to have been cut/failed.  The original configuration of the sling was a pretty standard two bolt equalization with a double length runner and a master point knot (this was a Bluewater Titan sling.)  The below image is how it was found when photographer John Dickey jug'd up to it.  I had mini-traxioned on the rope a few times during the previous couple weeks though I hadn't gone all the way to the anchor since fixing the rope.  While mini-traxioning I'd done some hanging and falling though not that much.  This pitch was 12- or so and didn't take that much work to figure out.  I'd say the anchor saw a small amount of use.  

We were pretty shocked to find the anchor like this and couldn't easily figure out a cause.  The the sling was only a few years old but had only been used a handful of times previously.   I owned about 10 of these double length runners that were used exclusively for fixing ropes on photo shoots or new routes and had never been used in my day to day climbing.  Rock fall was my initial thought but the abrasion that would of been caused by such an event wasn't present.  There was no abrasion, impact marks anywhere on the sling/knot, nor was there any dust or debris.  Second thought was the sling was cut over an edge, but again there lacked any abrasion so this didn't seem like the cause.  We also thought it could of been a rodent but the cuts were extremely clean and looked similar to how a knife would cut a sling.  So that was my final hypothesis, somebody had sabotaged my lines which has happened to me before up in Tuolumne (which had nearly killed me...) .  But that didn't add up to me.  If someone went up and intentionally cut the sling they would of also cut the backup knot in the rope going to the lower bolt.  And they would of also had to rappel this this setup as it was the only way off the cliff.  I'd also only left the ropes unattended for a few days out of the last couple weeks so somebody would of had to known when I wasn't going to be up there.  Again all of this was highly unlikely.  

I decided to send the sling into a friend of mine who does quality assurance at a large climbing manufacturer.  I'm not going to say who or use his name but he has as much experience as anyone I know in the field.  He came up with all of the same ideas as me but also ruled out that it broke due to a high load.  He said that there would of been melting where the sling had failed due to the high loads.  There wasn't any melting present.  He jokingly agreed that someone was trying to kill me and used a knife.  He said the cut looked identical to a sling that was cut with a knife.  Though he also agreed that leaving the backup knot foiled that plan.  His final idea what that the sling had actually cut it self.  He believe that one edge of the sling was crossing the cut area perpendicularly.  This "sharp" edge of the sling had slowly sawed through the piece it was laying on on.  He thought it was possible that the slight movements in the rope due to wind and or mini-traxions had caused this micro sawing action to occur.  This same failure method was also a possible cause of John Sherman's dyneema sling that broke in 2006.  More can be read about that incident on supertopo.com

What I learnt in the end was to never rely solely on a non supervised sling.  Always clip the rope directly into the anchor like I'd thankfully done.  Since this incident I've actually stopped using slings at anchors while fixing.  I now just use butterfly knots to equalize and attach the rope directly to the bolts taking out a possible point of failure.

Wasn't there huge rockfall on this route? Seems like the most likely explanation...that or rodents...

Mikey Schaefer · · Reno, NV · Joined Jun 2014 · Points: 233
mpech wrote:

Wasn't there huge rockfall on this route? Seems like the most likely explanation...that or rodents...

The rockfall was below and to the left of this anchor and only hit the first 5 pitches.  This rockfall did indeed cut my ropes but that is a different story.  And if you have ever seen rope or slings damaged by rockfall they generally look a lot different than a sling cut with a knife or even chewed on.  I've seen plenty off all types.  And rockfall would also leave a mark on the rock where it impacted, nothing like that was observed.  The sling looked almost brand new except for where it was cut.

20 kN · · Unknown Hometown · Joined Feb 2009 · Points: 1,346
Joe Crawford wrote:

Except that he's not. The SPI is not a guide track program in the AMGA and is not intended to produce a guide for anything beyond a top-roping venue. I'm sorry, but if you think that the guide services are going to pay a certified rock guide to teach beginnner top-roping courses, you're high. SPI commands $150-$170/day depending on area, while a certified guide is ~$250/day.
If a company chooses to hire an SPI for guiding beyond this scope they are not operating within the AMGA scope of practice and are not employing guides within their training. That is not a problem the AMGA has any power to do anything about.
However to make a blanket statement that 98% of guides aren't qualified is just embarrassingly ignorant. Sure, if you are at a single pitch area you're going to run into incompetence. Guiding in alpine venues, or more complex rock venues is increasingly dependent on training and certification and as a result our clientele is getting a guide that is held to a higher standard than experience alone. I'm not saying the AMGA certs make the guide, but what that cert does say is that the guide is dedicated enough to learn from and be examined by some of the best n the industry. I happen to work with one such guide who after decades as a guide in Yosemite felt that IFMGA certification was important enough to pursue and complete it in his early 50s. 

Guide/ climbing instructor, whatever. They are interchangeable terms for 99.9% of the population when referring to someone who teaches or proctors climbing outdoors. I clearly said that I believe the AMGA Rock Guide track is legitimate. I never said otherwise and I certainly did not say "98% of guides arnt qualified...". What I said what that HJ was correct in his original statement about the sole presence of having an AMGA certification by itself doesent mean much. Throwing out that you're AMGA certified and commanding respect as a result is not going to impress anyone.

Yes, I have seen actively-employed AMGA certified Rock Guides teach top roping courses to noobs. I know a guy who works for a very well-known and respected guiding outfit and if he has no clients to take up multi-pitch routes, then he is teaching the 101 noob course. At the end of the day if your boss tells you he needs you to go teach this newbie class then that's what you're doing. I doubt many rock guides are going to only accept multi-pitch guiding and say they would rather stay at home making $0 than teaching basics on the ground and getting paid.

Also, if you think Rock Guides spend all day taking people up 5.12s your wrong. The vast majority of guiding is taking noobs up easy climbs 5.10 and under, but even more commonly 5.9 and under. I've climbed with four people Rock Guide certified, only two of them has taken a client on a multipitch climb rated 5.12 and they aided the 5.12 sections. The other only took one client up a 5.12a in Squamish. Even climbing 5.11 is not that common. One said in five years he's only had about a dozen clients go up 5.11 climbs, and most of them 5.11-. So yea, even as a Rock Guide the vast majority of your clients are going to be looking for easy stuff.

ebmudder wrote:

Healyje and 20kN...both of you referred to "moderate" use of the gear, but that probably means something different to you than me. Can you roughly characterize how many days a year "moderate use" represents? You might think 100 days/yr is moderate but sadly that might represent 3-4 yrs of use for me!

Moderate being one a week. Weekend-warrior-type status. So probably 40 - 60 days a year. However, I dident say anything about moderate use. I just said tying knots in a Dyneema sling is going to reduce it's strength.

Dan Africk · · Brooklyn, New York · Joined May 2014 · Points: 275
Healyje wrote:

I live in the PNW so we have a relatively short season. "Moderate" for me means somewhere between 5-10 pitches once or twice a week from roughly mid-April thru mid-October. Roughly 27 weeks more or less. Call it 10 pitches / week so very roughly 270-300 pitches / year - could be 25% more or less depending on the weather and my client workload in any given year. 

270-300 pitches a year is moderate? Damn I wish I was a more moderate climber! I just checked  my stats, and I haven't lead more than 50 pitches in a year.. If you include pitches I've followed and top-roped outdoors (which I don't tick), it would still be well under 200.

Definitely an important clarification.. I would describe your use as heavy. Then again, I just noticed you mention 'client workload', are you a climbing guide? I think for guides (or any sort of professional climber) it's a whole different scale, the lightest season you ever have will exceed a heavy year for the average recreational climber, and your climbing gear will always fall into the 'heavy use' category..

Healyje · · PDX · Joined Jan 2006 · Points: 422
Dan Africk wrote:

Definitely an important clarification.. I would describe your use as heavy. Then again, I just noticed you mention 'client workload', are you a climbing guide? I think for guides (or any sort of professional climber) it's a whole different scale, the lightest season you ever have will exceed a heavy year for the average recreational climber, and your climbing gear will always fall into the 'heavy use' category..

No, definitely not a guide (at least of the climbing variety), I have a software consulting company and a startup which means I'm pretty much slammed day and night, six days a week most weeks unless I catch a break to play hooky for an afternoon. Luckily we have some good crags 25-45 minutes from the office (when it's nice out) so I can get in a few pitches in just a couple of hours if I'm quick about it (and rope soloing helps a lot as it doesn't matter if I have a partner or not).

20 kN · · Unknown Hometown · Joined Feb 2009 · Points: 1,346
Dan Africk wrote:

270-300 pitches a year is moderate? Damn I wish I was a more moderate climber! I just checked  my stats, and I haven't lead more than 50 pitches in a year.. If you include pitches I've followed and top-roped outdoors (which I don't tick), it would still be well under 200.

Definitely an important clarification.. I would describe your use as heavy. Then again, I just noticed you mention 'client workload', are you a climbing guide? I think for guides (or any sort of professional climber) it's a whole different scale, the lightest season you ever have will exceed a heavy year for the average recreational climber, and your climbing gear will always fall into the 'heavy use' category..

I call 270 a year the upper end of moderate. If you're climbing eight pitches per day, that's only 17 weekends and that assumes you dont take a climbing vacation. If you're on a climbing trip, you can crank that in 45 days or less. Even if you only climb 4-5 pitches a day, you would still climb more than 270 in a year if you climb most weekends.

Guideline #1: Don't be a jerk.

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