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Using a single strand of webbing for an anchor
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By SLippy
Apr 14, 2013

I have only ever seen webbing used when it is looped with a water knot. What is to stop you from using it non-looped like one would use (or how I have seen used) a static rope or cordalette?

I guess this is a pretty broad question but for example if you were using two trees that are too big to sling. And maybe you only have enough webbing to extend over a cliff if you don't loop it.

anchor
anchor

Here there are any number of knots you can use to tie one end of the webbing around the tree. I was thinking a bowline or fig. 8 (or double versions of these-and with backup knots of course). Ex how the static rope is used here climbingtechniques.wordpress.com/2012/07/01/how-to-set-up-a->>>.

Would this be ok with webbing? My guess is that sure it is fine-though maybe not ideal. Why would looped webbing-ex a long runner be better? Just b/c force would be split between two strands? Is there any better way to do this (using just webbing)? Am I just being oblivious and people already do this?

I guess similarly if you wanted to make your own metolius equalizer www.metoliusclimbing.com/equalizer.html you could just tie a knot at the end of 10' of webbing. Would this be safe? (I don't see why not). What knot would you use?


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By Robert Cort
Apr 14, 2013

It really comes down to knowing the strength of the materials you are using, and whether or not it's redundant. 1" tubular webbing is rated for 4000lb (17.7KN). Less 30% for knots.


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By SLippy
Apr 14, 2013

Ok so after looking into it one reason why you might not want to do this is that webbing is much weaker than static rope. Ex

blue water webbing
9/16"- 9kN
1"-17.8kN

blue water assaultline static rope-36.58kN
PMI e-z bend static line-26.9kN

PMI 7mm cordalette-10.7kN
New England 7mm cord-10.2kN
PMI 6mm Cord-6.8kN
Blue water dyneema 5.5mm cord-13.7kN
PMI 8mm cord-14kN

so in reality you would probably be fine on a sing strand anchor using any of these- but i really would only feel comfortable on a single strand of static rope.


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By SLippy
Apr 14, 2013

well robert got to it first


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By Steve Levin
From Boulder, CO
Apr 14, 2013
Sundevil Chimney, Titan

You do not have redundancy at the clip-in point in the "anchor" illustration you posted. To make this anchor set-up redundant, simply tie two overhand bights side-by-side (aka "Rabbit Ears") and clip your two lockers into each of these.


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By Andrew Rivera
Apr 14, 2013
climbing on an old dam

I don't have much authority on the subject but my first instinct is to avoid tying more knots than I have to. 1. because it increases the chance for human error and 2. knots will lower the strength of the webbing/rope/sling etc. My two cents. I'm more interested in seeing what others have to say


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By SLippy
Apr 14, 2013

good point didn't notice that


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By Brasky
Apr 14, 2013

first of all if your using webbing use a water knot, second what ever your wrapping the webbing around like a tree or boulder wrap it 2 or 3 times the friction from the wraps will be enough to take alot of the force off the knot. You probably dont wana use webbing for this kinda setup because top rope anchors gewt waited alot and have you ever tried to take a water knot out of webbing afdter youve waited it? and as for redundecy i guess two ropes are better than 1 but if your worried that your rope is gana cut or snap then why would you be doing it??? your rope or webbing is dynamic and can absorb force. it should be the strongest part of the system---(knots can absorb impact because some of the force from the fall gets taken into by the knot tightening on itself)


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By SLippy
Apr 14, 2013

well i wouldn't be able to tie a water knot b/c i am not tying it to the other end of the webbing-i am just tying one end to itself/around a tree.

and i am not worried about the webbing being cut-i am worried that the potential force would be too much for a single strand of webbing but it would be fine on a doubled strand like you would see in a runner.


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By Darby
From Snoqualmie, wa
Apr 14, 2013

I worry less about things breaking and more about anchors pulling out. I wouldn't worry at all with webbing tied to a BIG tree, one strand or not. What is the big load your fearing your anchor will take?


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By NYClimber
From New York
Apr 14, 2013
Awesome slab climb right out of the water! Rogers Rock, Lake George, NY. Summer 2013.

I'd rather use a 50 ft length of 7/16" or 1/2" static rope myself for rigging anchors like that. Static rope is strong and I think easier to tie and untie knots in and of of after weighting it.


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By Woodchuck ATC
Apr 14, 2013
Rock Wars, RRG, 2008

Also the fact that you as a trad climber years ago, carried those web sections as pre tied loops around your neck or body. There was convenience in their assembly and readiness for looping or to tie off with a figure 8 from multiple point anchors. A long strand of web with a loop on each end was not practical to carry, and certainly too much work to untie the water knot and then retie 2 new ends up for such a setup.


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By SLippy
Apr 14, 2013

Well toproping can generate pretty big forces. For ex. this rock and ice article says www.rockandice.com/lates-news/top-roping-is-not-so-safe up to 1500 lbs- which is almost 8kN-a bit too close for comfort for me to the breaking point of a thin piece of cordalette or webbing


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By HangDoug
Apr 14, 2013
CO

you can certainly use a water knot to tie the webbing around the tree without tying it to the other end.. if you can figure that out I fear for you a bit.


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By cellige
Apr 14, 2013

I just wanted to chime in here real quick, the knot you should use IS the water knot. It is an overhand follow through. DO NOT just tie the webbing around itself. Tie an initial overhand knot, wrap around tree and then follow through the initial knot. Sorry if you know this but you mentioned you can't use the overhand knot so a red flag went up.


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By SLippy
Apr 14, 2013

ok yeah guess you are right on the water knot. guess my mind isn't wired to think of it being tied that way


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By SLippy
Apr 14, 2013

so yeah tying and untying water knots would be a big pain- especially if they were weighted


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By SLippy
Apr 14, 2013

some other trust you life to what random people on the internet say sites seem to think that bowline on a bight and overhand on a bight are fine with webbing- which would make the setup more practical to setup and disassemble. thoughts?
www.canyoneeringusa.com/techtips/webbingknotsparttwo/
www.forums.caves.org/viewtopic.php?f=5&t=6653
www.rockclimbing.com/cgi-bin/forum/gforum.cgi?post=2573368


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By bearbreeder
Apr 14, 2013

it will work fine ... get full strength (20kn+) webbing, pad any sharp edges, and make sure the masterpoint aint rubbing against anything

ask yourself this ... how is it going to fail ... rather than asking about TR anchors on the intrawebs, which brings everyone out of the woodwork ;)


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By Michael C
From New Jersey
Apr 15, 2013
Base of Main Flow, The Narrows.

my biggest fear with webbing is that it is not going to be as abrasion resistant as 7mm+ cord or static rope. and like most climbers, whenever I rap off of webbing I use two independent strands. the only time I've used webbing in a TR setup was if one of the trees I was using was WAY back and my static wouldn't be enough. but I've never had the master point be made from webbing, or extended webbing over an edge like I would with cord/static.

one thing I always do, and tell other climbers to do, is make sure the water knot's tails are several inches long AND to tie overhand knots in them. a study was done, and if the water knot slips the overhand knots prevent the tails from passing through.


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By Morgan Patterson
Administrator
Apr 15, 2013
Stoked...

bearbreeder wrote:
it will work fine ... get full strength (20kn+) webbing, pad any sharp edges, and make sure the masterpoint aint rubbing against anything ask yourself this ... how is it going to fail ... rather than asking about TR anchors on the intrawebs, which brings everyone out of the woodwork ;)


+1 come to CT if you want to see examples of TR anchors with or without redundancy.


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By rging
From Salt Lake City, Ut
Apr 15, 2013
CoR

SLippy wrote:
I have only ever seen webbing used when it is looped with a water knot. What is to stop you from using it non-looped like one would use (or how I have seen used) a static rope or cordalette? What knot would you use?


Two issues. Material is strong enough but I have seen long pieces of (single strand) webbing extended over a lip stretch more than you would realize and make a sawing action so make sure you deal with that. It was more of an issue for me with constant rappelling than top rope climbing but a sharp edge will slice webbing in half faster than a rope. The other issue is knots. You need to be very careful about the knots that you use. Webbing does not tie like rope at all. I would only use a water knot, overhand on a bight or eight on a bight which means you would have to use your setup with a girth hitch (which you need to be careful with too). If you go to a canyoneering site they will have several different rigging styles you can learn from.


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By rging
From Salt Lake City, Ut
Apr 15, 2013
CoR

SLippy wrote:
some other trust you life to what random people on the internet say sites seem to think that bowline on a bight and overhand on a bight are fine with webbing- which would make the setup more practical to setup and disassemble. thoughts? www.canyoneeringusa.com/techtips/webbingknotsparttwo/ post=2573368


Information you get from canyoneeringusa is rock solid. Tom Jones has decades of experience as a climber, canyoneer, and canyoneering guide. He has worked at Black Diamond as an engineer and is an MIT grad. I have been out with him, used products he designed and would trust him with my life.


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By M Sprague
Administrator
From New England
Apr 15, 2013
Lichen head. Me, with my usual weatherbeaten, lichen covered look from scrubbing a new route.

When in CT, I prefer 1/2" logging chain since it can handle abrasion. I usually take a 50 foot piece along for TRing. Of course the gumby in the party gets to carry it.


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By MJMobes
From The land of steady habits
Apr 15, 2013
modern man

rging wrote:
a sharp edge will slice webbing in half faster than a rope


really, have you tested that theory out? I beg to differ sir.


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By Buff Johnson
Apr 15, 2013
smiley face

I wouldn't a thought of it, but cool.

Nothing says gumby-tard faster than bringing 50+' of webbing to a crag; when a hundred foot smaller static would seem more workable to me.

I guess if you were gonna TR some ice, you could use the webbing on the approach like one of those old-school avy cords and just trail it off your haul loop


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