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Best webbing to use for alpine draws?

Bootz Ylectric · · Las Vegas, NV · Joined Apr 2012 · Points: 165
alexdavis wrote: Can someone explain the physics behind the fact that creating a loop doubles the strength of a single strand? Never quite understood that one.
Think load distribution. It's not doubling the strength but spreading the impact out thus lessening the impact hitting at one point.

I'm too new and inexperienced to say, but the thought of tied or home sewn slings makes me nervous. I'm perfectly happy just buying ones pre sewn, bar tacked, rated and tested to hold.
Colonel Mustard · · Sacramento, CA · Joined Sep 2005 · Points: 1,241

I just bought some tubular nylon webbing and made a couple of "alpine draws". Cheap as fuck and nylon ties and unties well for potential bail situations. Dyneema isn't good for that. I wouldn't want every draw to be such but having a couple constitutes an advantage in my book.

DannyUncanny · · Vancouver · Joined Aug 2010 · Points: 100
iceman777 wrote:Leeroy Nice to see someone knows the real deal , good on ya man and ill bet yer aiders n such work just as good as the store bought stuff huh, If anyone wants to roll there own just get your hands on a copy of the mountaineers handbook. lots n lots of useful info on how to sew your own, And on how to tie the "Beer Knott" Oh yea NO NO NO you dont need a bartacker machine just some good strong thread and make a shitton of passes it works fine , hell truth be told on mine the webbing broke before the stiching when we did the pull test w my jeep grand cherokee so if it will hold my jeep ....well you get the drift . However I dont roll my own I buy mine there not that expensive ,considering you really dont need that many slings its prolly one of the cheapest expences you will have building your rack. Ah yes to thoes of you neysayers let me state this " I suggest you do some reserch before letting your inexperienced mouth overload your ass!" cheers
I just picked up a 1962 Singer sewing machine at a yard sale. It's supposed to be able to stitch leather. I'm going to try a few slings with some webbing lying around. The strongest thread I could get a hold of was high strength nylon. Any idea how it will hold up?
Mark Mueller · · Surprise, AZ · Joined Nov 2011 · Points: 185

I really like the Trango Ultratape slings for my alpine/trad draws.

Dood · · Chattanooga, TN · Joined Feb 2012 · Points: 370

We use 4ft 1" bluewater tubular nylon runners which are rated at 32kN (around 4.25$ per at my local Rock Creek.) Get something stronger than your safety requirement if you're going to tie knots in it, as the knots will weaken the runner's strength. The 48 inch runners seem to make a perfect QD size when tripled and are perfect for protecting deep inside cracks and roofs when single.

Allen Corneau · · Houston, TX · Joined May 2008 · Points: 80
ChillFancy wrote:We use 4ft 1" bluewater tubular nylon runners which are rated at 32kN (around 4.25$ per at my local Rock Creek.) Get something stronger than your safety requirement if you're going to tie knots in it, as the knots will weaken the runner's strength.
1" webbing slings is overkill.

BW Titan runners (my favorites) are 27kN and half the width/weight (a lot less bulk) .
Colonel Mustard · · Sacramento, CA · Joined Sep 2005 · Points: 1,241
Jake Jones wrote:A few tied webbing slings if you're old school like Custer and want to be really diverse and have an extra tool if you need it. My $.02
Hell yeah, dude! I just bailed today off some bolted anchors without rings/links/walkoff/etc. using my nylon and a rap ring I carry in my chalk bag!
Robbie Mackley · · Tucson, AZ · Joined May 2010 · Points: 85

For what its worth. An article in Climbing magazine a few months back sights not carying any tied runners as one of the top 10 amature mistakes made by experienced climbers. Carry a selection of different runners, long, short, tied, sewn, nylon, dyneema, etc. and you should be gravy. Climb safe out there.
-Mackley

GonnaBe · · Unknown Hometown · Joined Nov 2010 · Points: 135
Old Custer wrote:I just bought some tubular nylon webbing and made a couple of "alpine draws". Cheap as fuck and nylon ties and unties well for potential bail situations. Dyneema isn't good for that. I wouldn't want every draw to be such but having a couple constitutes an advantage in my book.
I've bailed off a partner's hand tied runner as well. He keeps two double length runners that are hand tied on his rack. When it was time to bail out they came.

He was also using 9/16 tubular webbing. But a whole set of them?!
mountainhick · · Black Hawk, CO · Joined Mar 2009 · Points: 120
Old Custer wrote: Cheap as fuck and nylon ties and unties well for potential bail situations.
zzzzzactly,

Mostly sewn runners here, plus one or two 9/16" double over the shoulder length knotted runners and a knife for exactly this. Adjusting sling length with the knot can also be helpful in some situations.

You could cut up a sewn runner as needed too, I just like having the versatility.
Gareth Baron · · Unknown Hometown · Joined Dec 2013 · Points: 5

OK, so I'll chime in my $0.02.

11/16" webbing from Sterling is rated at an MBS of 3000lb = 13.34kN.

So if you loop it you get 26.68kN. Now tying a water knot will give you an efficiency of worst case 65% , which leads to 17.3kN.

[BTW a Beer knot is 80% efficient apparently but I'll use a water knot in these calcs for a worst case scenario.]

This is probably adequate for an alpine draw (but I wouldn't risk it). Especially if you loop the draw 3x (6 strands as normal for storage/short draw). On the short [non extended] draw you would have ~41kN. On the extended draw you would have 17.3kN.

A typical leader fall is between 3-7kN. Using 7kN: So you have ~2.5x redundancy factor in the minimum case and 9x in the best case. FWIW, the rigging industry expects a 5:1 (ie 5x) redundancy factor.

If you were using a sewn runner (17mm = 11/16") you would have ~3.8x in the minimum case and 11.4x in the best case.

So in a nutshell, home-made water knot 11/16" gives you worst case 2.5x redundancy factor, a bar-tacked sewn runner gives you 3.8x redundancy factor.

However there is definitely a use and a utility of your own home made draw. Make a regular short draw that normally doesn't get extended. You can then use the webbing to build a 3 point anchor. Eg have a lengthy draw (which has 6 strands - a short alpine draw), eg 3 ft that extends to 9ft, and you can make a bomber anchor out of it as well as using it as a draw if need be.

For a 3 point anchor using a single loop (ie your own sling) you can make each leg support up to 17.3kN. This is way stronger that any trad gear piece you may have. 3 points = ~41kN which is a bomber anchor.

The 3 point anchor I refer to is basically a bend at each 'biner and then the whole thing tied off in an overhand master point knot after equalizing the legs.

mountainhick · · Black Hawk, CO · Joined Mar 2009 · Points: 120
mountainhick wrote: zzzzzactly, Mostly sewn runners here, plus one or two 9/16" double over the shoulder length knotted runners and a knife for exactly this. Adjusting sling length with the knot can also be helpful in some situations. You could cut up a sewn runner as needed too, I just like having the versatility.
Hmm changed my tune from when I posted this based on an oops moment a year or more ago.

Back when there were no sewn runners and everything was knotted, it was part of the ritual to inspect water knots every day of climbing.

Having used sewn runners more and more through the years, I got complacent about this check. I lead a pitch, set up pretty much this kind of anchor on a couple bolts, though with a knotted runner. Envision the sewn bar tacked area as a water knot:



Then cloved in, went off belay, pulled up the rope, set up an ATC in guide mode and was just about to yell on belay when I looked at the water knot and saw only one tail.

A bit surprised, embarrased and realizing I really only had half the anchor I thought I did, I redid it and retied the water knot before putting my partner on belay.

So, the lessons learned. Either be sure to check those water knots evey time, or just use sewn runners.

My own long term solution is that I don't carry knotted runners any more when climbing, but usually keep one in my pack in case I want to replace tat a pitch off the ground. Higher up, I always have a knife in the chalk bag pocket anyway so can cut up sewn runners if needed. Haven't yet though.

The only remaining possible advantage to knotted runners for me is threading through natural openings for anchors. There are times when one strand will work, but not two. Rare, but it happens.
Gareth Baron · · Unknown Hometown · Joined Dec 2013 · Points: 5

Great info and thoughts.

I completely agree with you about taking a modern-day dyneema/spectra 240cm runner with you. Light, strong, can be used for anchor/quickdraw/looping a chicken head etc.

I was just illustrating the math to show how strong 11/16" nylon webbing is. Yes, you can cut your 240cm runner but tying knots in dyneema/spectra can be suspect, so be careful and understand what material you are working with.

Nylon webbing is still damn good for it's dynamic qualities.

Jim Titt · · Germany · Joined Nov 2009 · Points: 490

Webbing is tested in a different way to sewn slings, over a karabiner webbing gets considerably less than the rated strength. Doubled or tripled over a karabiner we normally see a reduction in strength as well (compared to a single loop) as the outer strand cuts the inner one. Wide nylon is particularly bad for this and doubled I´d prefer to use thin Dyneema as there is less chance one layer lies on the other.

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

The UIAA requirement for a sling or dogbone is 22kN. If you just needed a quick sling on a multipitch route and ran out of draws, sure 9/16" is fine. But I would not create an entire rack of 9/16" draws. When you consider wear and UV exposure, after a year the strength could dip below 10kN easily. Now, if we are talking about 11/16", that's better, although I would just go with the correct sling. Right tools for the right job.

20 kN · · Unknown Hometown · Joined Feb 2009 · Points: 1,346
Gaz wrote:FWIW, the rigging industry expects a 5:1 (ie 5x) redundancy factor.
For non-critical applications it's 5:1. For critical applications, it's typically 7:1 and for life-support applications it's 10:1, and I have seen as high as 15:1 for life support.
Derek Doucet · · Unknown Hometown · Joined Apr 2010 · Points: 66
Robbie Mackley wrote:For what its worth. An article in Climbing magazine a few months back sights not carying any tied runners as one of the top 10 amature mistakes made by experienced climbers. Carry a selection of different runners, long, short, tied, sewn, nylon, dyneema, etc. and you should be gravy. Climb safe out there. -Mackley
Apparently it's not worth much.
mountainhick · · Black Hawk, CO · Joined Mar 2009 · Points: 120
20 kN wrote:The UIAA requirement for a sling or dogbone is 22kN. If you just needed a quick sling on a multipitch route and ran out of draws, sure 9/16" is fine. But I would not create an entire rack of 9/16" draws. When you consider wear and UV exposure, after a year the strength could dip below 10kN easily. Now, if we are talking about 11/16", that's better, although I would just go with the correct sling. Right tools for the right job.
After a year of normal use being carried while climbing? Where did you come up with that?

I have read the BD sling testing article, but it was not a controlled study, using slings that had been on outdoor anchors for unknown periods of time. And the "alarming" early failure aspect of those tests were based on material that had been on exposed outdoor anchors.

Is there some other testing you are referring to?

If nylon deteriorated that quicky, slings on cams would also need replacement yearly.

Certainly a serious concern for slings tied on to outdoor anchors.
Avalon'cha · · your girlfriend's bedroom · Joined Aug 2013 · Points: 35
iceman777 wrote:Leeroy Nice to see someone knows the real deal , good on ya man and ill bet yer aiders n such work just as good as the store bought stuff huh, If anyone wants to roll there own just get your hands on a copy of the mountaineers handbook. lots n lots of useful info on how to sew your own, And on how to tie the "Beer Knott" Oh yea NO NO NO you dont need a bartacker machine just some good strong thread and make a shitton of passes it works fine , hell truth be told on mine the webbing broke before the stiching when we did the pull test w my jeep grand cherokee so if it will hold my jeep ....well you get the drift . However I dont roll my own I buy mine there not that expensive ,considering you really dont need that many slings its prolly one of the cheapest expences you will have building your rack. Ah yes to thoes of you neysayers let me state this " I suggest you do some reserch before letting your inexperienced mouth overload your ass!" cheers
& my custom fitted juggin' rig is a bomb a$$ truck thats quiker than 4uck!! WOOTIE WOOOOOOT :O Works even better froggy style:)
apogee · · Unknown Hometown · Joined Nov 2009 · Points: 0

So I'm shopping for new sewn runners, and would've preferred the better handling and weight advantages of 9/16" nylon runners (as a supplement to the Mammut 12 mm dyneema 'Contact' runner). Sounds like the 9/16 option is pretty much not an option any longer due to the fact they can't even approach the 22 kn UIAA standard. Understandable, but still kind of a bummer.

That means that 11/16 is about the only realistic option (short of making my own 9/16", which I'm not interested in doing). Which sewn nylon (NOT dyneema) runners do you like? Why?

Guideline #1: Don't be a jerk.

Trad Climbing
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