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Preventing the sling from unclipping from the biner

Original Post
bearbreeder · · Unknown Hometown · Joined Mar 2009 · Points: 3,065

from this accident

mountainproject.com/v/climb…

- long draws, snake cord, rabbit runners

- locker or opposed biners (also prevents rope from coming out)

- clove or overhand the end of the sling for the rope side biner



snake cord 7mm cord, dmm biners

10mm dyneema sling cloved into WC nitro biner
eli poss · · Durango, CO · Joined May 2014 · Points: 525

Never tie an overhand in a dyneema sling as it reduces strength. Does this also occur with a clove? Why not just use a rubber band to fix the rope end biner?

bearbreeder · · Unknown Hometown · Joined Mar 2009 · Points: 3,065
eli poss wrote:Never tie an overhand in a dyneema sling as it reduces strength. Does this also occur with a clove? Why not just use a rubber band to fix the rope end biner?
your newbness is showing

everyone ties knots in dyneema all the time

the question is ... is there a dynamic rope in the system
Kris Holub · · Boulder, Colorado · Joined Jan 2011 · Points: 70

Posted this in the previous thread just before this was made:

Do wiregate/non-locking gridlock biners exist? I've only ever seen lockers with the gridlock feature, which is overkill for 99.99% of the time. If such a piece existed, it would prevent this failure mechanism while still being lightweight and practical.

Nkane 1 · · East Bay, CA · Joined Jun 2013 · Points: 140
eli poss wrote:Never tie an overhand in a dyneema sling as it reduces strength. Does this also occur with a clove? Why not just use a rubber band to fix the rope end biner?
This video shows why you shouldn't use a rubber band to secure the rope-end biner.
bearbreeder · · Unknown Hometown · Joined Mar 2009 · Points: 3,065
Kris Holub wrote:Posted this in the previous thread just before this was made: Do wiregate/non-locking gridlock biners exist? I've only ever seen lockers with the gridlock feature, which is overkill for 99.99% of the time. If such a piece existed, it would prevent this failure mechanism while still being lightweight and practical.
http://www.mec.ca/product/5036-334/edelrid-pure-slider-biner/

mec.ca/product/5038-160/gri…

or did you mean non-crossloading ones?
BigFeet · · Texas · Joined May 2014 · Points: 385

... getting popcorn.

At least we went straight to the issue this time.

Good information, bearbreeder!

Kris Holub · · Boulder, Colorado · Joined Jan 2011 · Points: 70
bearbreeder wrote: mec.ca/product/5036-334/ede… mec.ca/product/5038-160/gri… or did you mean non-crossloading ones?
Well I'm pretty sure gridlock is the correct term, but yes non-crossloading. Think this but without the screwgate:

backcountry.com/omega-pacif…
bearbreeder · · Unknown Hometown · Joined Mar 2009 · Points: 3,065
Kris Holub wrote: Well I'm pretty sure gridlock is the correct term, but yes non-crossloading. Think this but without the screwgate: backcountry.com/omega-pacif…
sorry kris ... im not aware of any such

i suspect that if they existed they would a biatch to take off and put back on extendable draws anyways ...

and a clove/overhand serves the same purpose

one note .. for your big fellahs out there a clove/overhand shortens the sling a bit so it may be harder for you to take it off your shoulder

also for cams if you use extendible draws (sling+2 biners) on a cam you can just take the spare biner off the cam and put it opposed on the rope end

of course there is always the possibility of the sling coming off the top (pro) end as well
J. Albers · · Colorado · Joined Jul 2008 · Points: 1,926
bearbreeder wrote: your newbness is showing everyone ties knots in dyneema all the time the question is ... is there a dynamic rope in the system
Meh. Aside from hitching natural protection, I don't ever tie dyneema in knots. In general its not a great policy, so your snide comment to Eli is not particularly justified. Then again, Eli speaking in absolutes -- i.e. using the word 'never'-- is also problematic. Anyway. Carry on.
Jon H · · PC, UT · Joined Nov 2009 · Points: 118

Damn it. I typed out a long response but accidentally clicked a link on the page and lost the whole thing.

Admins - what about MP causes this? Most other websites and forums will persist all text entry if you navigate away and back to a page. This has happened to me more than once here.

Anyway...

Metolius long dogbones are the cleanest, strongest, and lightest option. Also most expensive. Also harder to hitch onto natural pro, e.g. hitching it onto a chickenhead.

Cloving a standard dyneema runner to the rope-end carabiner will work, but the reduction in strength is significant and could become the weakest link. I'd be concerned about using this on the first 1-3 placements off the belay. Also, clove hitches under load will weld themselves impossibly tight. Can this action cause damage to dyneema? What about over time and repeated loadings? Has it ever been studied?

I quite like the idea of a single strand of cord with a carabiner attached via barrel knot to each end. Very inexpensive. Great for alpine climbing where beefing up rappel anchors is a regular occurrence. Anyone have the data off-hand for what diameter cord needs to be used to maintain >10kn after knotting? I would guess 8mm.

Jon H · · PC, UT · Joined Nov 2009 · Points: 118
eli poss wrote:Never tie an overhand in a dyneema sling as it reduces strength. Does this also occur with a clove? Why not just use a rubber band to fix the rope end biner?
Eli - speaking generally, there is no issue tying an overhand (or any knot) in dyneema. Yes there is a loss in strength, but not enough to induce failure when there is a rope in the system. The concern with cloving dyneema is more along the lines of can it ever be untied?

Rubber bands on open slings have now killed at least 2 climbers that I know of. Tito Traversa, and a woman at RRG whose name I can't recall. The rubber band obscures the sling end from view and it's extremely easy to have the sling in a configuration where the carabiners are not being held by the sling, but only by the rubberband. You should be able to infer the rest.

And yeah, bearbreeder can sometimes be a jerk, but he's right. You've made 2 posts today alone that show a general lack of knowledge/experience about technical climbing. It's cool though. We were all 18 once. I was 18 and dumb, which made life even harder. For now, give it time, and maybe consider slowing down a bit. Also, don't dispense info unless you're sure it's correct.
Ray Pinpillage · · West Egg · Joined Jul 2010 · Points: 180

Internet expert looks like an exhausting role.

metoliusclimbing.com/rabbit…

Brian C. · · Longmont, CO · Joined Feb 2010 · Points: 1,100

Makes me wonder how often this type of un clipping happens. I frequently use shoulder lengths like this without giving it much thought. If it traverses or an important placement I will use an extra, opposed carabiner on the rope but find that my partners will usually ask why I did that. Makes me wonder how often other peeps do this and how often it happens. Defintley had this accident in the back of mind the other day in Eldo.

eli poss · · Durango, CO · Joined May 2014 · Points: 525
Jon H wrote: Eli - speaking generally, there is no issue tying an overhand (or any knot) in dyneema. Yes there is a loss in strength, but not enough to induce failure when there is a rope in the system. The concern with cloving dyneema is more along the lines of can it ever be untied? Rubber bands on open slings have now killed at least 2 climbers that I know of. Tito Traversa, and a woman at RRG whose name I can't recall. The rubber band obscures the sling end from view and it's extremely easy to have the sling in a configuration where the carabiners are not being held by the sling, but only by the rubberband. You should be able to infer the rest. And yeah, bearbreeder can sometimes be a jerk, but he's right. You've made 2 posts today alone that show a general lack of knowledge/experience about technical climbing. It's cool though. We were all 18 once. I was 18 and dumb, which made life even harder. For now, give it time, and maybe consider slowing down a bit. Also, don't dispense info unless you're sure it's correct.
Hmmm I've never heard of that. Thank you for your insight. I understand that the rope will negate the need for pro to be dynamic but what if, later on, you find yourself needing to use that sling to attach yourself to an anchor? This is why I use nylon for my slings. Sure the knot reduces strength but with nylon, the knot also absorbs force, sort of like a rope, but to a lesser extent. And while it is true I am 18 and admittedly do stupid things, such as raping on 3mm cord, I also know how to be extremely safe, like a MPer. I have never been reckless when anyone else had their life in my hands. When I'm alone I may do stupid, reckless things but all that ends when I'm climbing with others.
bearbreeder · · Unknown Hometown · Joined Mar 2009 · Points: 3,065
Jon H wrote:. Anyone have the data off-hand for what diameter cord needs to be used to maintain >10kn after knotting? I would guess 8mm.
5mm tech cord is rated to 22 kn+ ... yes there is a concern about longer term durability but then its something youll replace more often like skinny dyneema slings

a barrel knot reduces the strength by ~ 30% ... so theres still 10+ KN after knots and a bit of wear and tear

using thinner cord with snake cord has a benefit in that the knot is less likely to stick in the biner when undoing "alpine draws" ... with 7 or 8 mm cord it can stick (not a safety issue, just annoying)

a meter of tech cord is ~ 4$ ...

also consider that its fairly light ... a 80 cm length (to allow for knots to simulate a 60 cm sling) would weight ~20g or so

i would use a triple barrel knot with a thin 5mm tech cord

as to cloving dyneema ... its fine IME ... the easiest way to undo a clove is not back and forth or trying to pull it apart ... but to move it from side to side across the biner ...

also remember that youll have rope in the system .. even a cloved dyneema 22 kn+ sling is rated to 14+ KN ... more than enough for any fall with the rope in the system

Mastwurf is another name for the clove hitch. 35% reduction in strength with a clove hitch.
Joan Lee · · Unknown Hometown · Joined Jun 2014 · Points: 140

I will pre hitch my long slings from now o for sure. Good point to be backing up the spare biner too. It is just hanging there anyway. I don't like those "rubber thingies" unless used on dog bones (properly). A hitch can be untied easily if you need to sling a rock or a tree. Finally when we put the bs aside we start to learn something from this site!

eli poss · · Durango, CO · Joined May 2014 · Points: 525

I know this is off-topic but curiosity prevails:

Can water knots in tubular webbing absorb more force than it reduces the strength of the sling? Has there been any testing on this? What about a fig 8 on a bight?
I use, for attaching myself to an anchor, a loop of 1" tubular webbing tied with a water knot and stopper knots backing up the tails. I then have a fig 8 for adjustability. I previously had overhand for adjustability but I didn't like how hard it was to untie so I replaced it with a fig 8. Am I gonna die?!

FrankPS · · Atascadero, CA · Joined Nov 2009 · Points: 276
eli poss wrote:I know this is off-topic but curiosity prevails: Can water knots in tubular webbing absorb more force than it reduces the strength of the sling? Has there been any testing on this? What about a fig 8 on a bight? I use, for attaching myself to an anchor, a loop of 1" tubular webbing tied with a water knot and stopper knots backing up the tails. I then have a fig 8 for adjustability. I previously had overhand for adjustability but I didn't like how hard it was to untie so I replaced it with a fig 8. Am I gonna die?!
Sounds fine to me. Probably don't even need stopper/backup knots for the water knot, either (if the water knot is properly tied with enough tail).
StonEmber · · Raleigh, NC · Joined Mar 2013 · Points: 35

Eli: you should never be "raping on a 3mm", it's unseemly....I believe what's being implied here, most importantly, is to not fall on anything static. A knot in a nylon runner may keep from blowing out, but that rusty bolt may beg to differ....

Eleanor: "rubber thingies" on dogbones? disgusting

Jim Amidon · · Unknown Hometown · Joined Jun 2001 · Points: 850

Dynamee when shock loaded is yes weaker that just nylon slings. The fibers are stiffer and thus will break under the right circumstances, and when knotted or hitched you compound the areas where excessive stress is added......

But what do i know I learned this in a rigging for rescue course from the instructors in Ouray.....

They had video proving how weak the mixed material was........Dynamee and nylon especially the skinny slings........

I got rid of all my skinny slings and went to all nylon, (which when loaded stretches unlike the Dynamee)

But wadda I know......

Guideline #1: Don't be a jerk.

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