Mountain Project Logo

Offset Top Rope Anchor

Original Post
Dave Dillon · · Tewksbury · Joined Feb 2015 · Points: 180

If the scenario is anchoring to bomber trees/boulders that are set back 15+ feet from the edge of the cliff you're climbing on. What type of anchor will you build? 11mm static rope, 7mm cord, or slings/webbing?

Seems like all are acceptable as long as you have enough length. but the 11mm static would be most robust and easiest to set up. Just wondering if anyone is using 7mm cord doubled up in this scenario if they didn't have a heavy static line with them.

This is educational and hypothetical.

Jorden Kass · · Belmont, MA · Joined Jan 2014 · Points: 0

I've used all three. I like static because it's easy and strong, but it is heavy. Webbing is light but I rarely use it (no reason just habit). 7mm I've used but usually only back a few feet since if I know it's farther I'll have static line

Brady3 · · Unknown Hometown · Joined Apr 2014 · Points: 15

I did this all the time while climbing in MO. I used webbing because it's cheap and is going to damage trees less than cord will. Try to keep it from sawing across the edge, though I never had a problem with this and all my webbing is still good (other than being cut up to be use for other things).

Henry Holub · · Altus, OK · Joined Nov 2015 · Points: 705

This is a regular scenario for me at the place I climb most of the time. I use webbing. Webbing is cheap and I find water knots to be incredibly easy to work with and adjust. One of the guys I climb with hates webbing and water knots. He uses a 11mm static line. I don't think you can go wrong with either

Dave Dillon · · Tewksbury · Joined Feb 2015 · Points: 180

But theoretically 7mm cord at 15-20 foot lengths is acceptable? Given that you have enough length to double up each leg?

Henry Holub · · Altus, OK · Joined Nov 2015 · Points: 705
mountaineeringlife.com/wp-c…

7mm static- single loop 19kn, double loop 38kn

It'll do the job
BigFeet · · Texas · Joined May 2014 · Points: 385

Acceptable... I would say that is all dependent on the persons who will be using it.

I would recommend something burly/robust and redundant. This will be a part of your system that you will not be watching closely, if at all. Keep some piece of mind when you can.

nathanael · · Riverside, CA · Joined May 2011 · Points: 525

7mm is plenty strong. BUT if there's sharp edges around it's a lot less durable. If you're going to be up there to monitor it, or if you're just running a couple laps before moving on, then great. If, on the other hand, you're set up to like a group of 10 people all running laps on it with no one checking the anchor then I'd go for something a bit heartier.

Henry Holub · · Altus, OK · Joined Nov 2015 · Points: 705

Most of the time I'd put higher priority on having my TR masterpoint where I wanted it (to reduce rope drag, be more directional, not load my masterpoint over an edge, etc)

Agreed

Dave Dillon · · Tewksbury · Joined Feb 2015 · Points: 180

Good point Nathanael, I guess this would be more of a "couple of laps and move on" scenario. Where I'd be using the gear I brought for a day out, which may not include a big heavy static. If I were with a group of 5+ it would be a no brainer to bring a 50-100 foot static along... Because I wouldn't have to carry it :-D

Thanks for the input!

Chris Owen · · Big Bear Lake · Joined Jan 2002 · Points: 11,617

I've used 50 foot lengths of webbing very successfully at Stoney Point for TR anchors off trees and boulders offset some distance from the edge. The key things to remember are:

1 - Equalizing the load on the masterpoint effectively.
2 - Eliminating SPOF (single points of failure)
3 - Reducing wear upon the anchor points, both webbing and anchor to a minimum
4 - Eliminating drag on the TR rope run
5 - Positioning TR rope run on the climb and not away from the climb

BigFeet · · Texas · Joined May 2014 · Points: 385
Henry Holub wrote: Most of the time I'd put higher priority on having my TR masterpoint where I wanted it (
For sure this is a priority, but with the situation described by the OP, I would say the anchor arms being protected over the edge, and anchor security would be high on the list as well.

With the question of smaller diameter cord being used over a long distance, the repetitive loading and unloading of the cord over an edge can cause damage/failure to the cord quite quickly. Pad the edge when and where you can!
alpinejason · · Minneapolis · Joined Apr 2010 · Points: 176

Why are people so weak they can't carry 4lbs of rope?

Dave Dillon · · Tewksbury · Joined Feb 2015 · Points: 180
alpinejason wrote:Why are people so weak they can't carry 4lbs of rope?
It's not really about the weight. It's about NOT having the big static available while you're out. Maybe not expecting to need it? But having something lighter available.
BigFeet · · Texas · Joined May 2014 · Points: 385
alpinejason wrote:Why are people so weak they can't carry 4lbs of rope?
In my case, it would only be because of the six pack of beer taking up the space.
rocknice2 · · Montreal, QC · Joined Nov 2006 · Points: 3,847

For long TR setups like that use a 9-10mm STATIC. Two single legs to a big tree and a rock tied off with a master-point is the best setup.
Those 7mm perlon/nylon cords are NOT true static. If your going to have these long legs they will stretch a lot. The 1" webbing will stretch less so but it will still stretch. By the time you double or triple up the loops to minimize the stretch you may as well just use true static rope. 11mm is a bit overkill. Maybe if you needed to go back 50'+

alpinejason · · Minneapolis · Joined Apr 2010 · Points: 176
rocknice2 wrote:For long TR setups like that use a 9-10mm STATIC. Two single legs to a big tree and a rock tied off with a master-point is the best setup. Those 7mm perlon/nylon cords are NOT true static. If your going to have these long legs they will stretch a lot. The 1" webbing will stretch less so but it will still stretch. By the time you double or triple up the loops to minimize the stretch you may as well just use true static rope. 11mm is a bit overkill. Maybe if you needed to go back 50'+
Do this always. Get stronger and carry a bigger pack to accommodate rope.
Gunkiemike · · Unknown Hometown · Joined Jul 2009 · Points: 3,492
rocknice2 wrote:For long TR setups like that use a 9-10mm STATIC. Two single legs to a big tree and a rock tied off with a master-point is the best setup. Those 7mm perlon/nylon cords are NOT true static. If your going to have these long legs they will stretch a lot. The 1" webbing will stretch less so but it will still stretch. By the time you double or triple up the loops to minimize the stretch you may as well just use true static rope. 11mm is a bit overkill. Maybe if you needed to go back 50'+
+1 for medium weight (9-10mm) static. 11 mm static is a beast to pack and carry.
Kevin Beadle · · Unknown Hometown · Joined Jul 2015 · Points: 0

I'm a big fan of 8mm static cord. I'm not a fan of a overly bulky master point I get with 11 mil. Also the approach where I climb is pretty steep hand weight is a factor for me. I do however bring tubular webbing with me as well. I usually don't use it but you never know.

r m · · Unknown Hometown · Joined Apr 2015 · Points: 0

What would *I* build? Some contraption of slings and 7mm cordelette, I don't own any static I use for climbing.
(I take some pretty long slings when setting up top ropes, 1.2m, 2.4m in burly nylon, or 4m in not burly dyneema.)
I generally try to have two redundant strands of the burly sling being the thing that takes all the wear and tear of the edge.

Another option is to belay from the top and run the climbing rope over the edge. Generally they're rounded edges around here. When it's not and I think rope cutting could-maybe-be-possible-in-some-far-out-universe, we'll use doubles. If there's actually an edge that I think poses a threat, rather than screwing around with trying to pad shit and make sure things don't shift about and all that faff, I find another climb.

Medic741 · · Des Moines, IA (WTF) · Joined Apr 2012 · Points: 265

7mm is fine... Tie a Prussik near the edge, clip it to the haul loop of your backpack and use that to protect the cord from getting cut. Clip waist/shoulder belts of pack around legs of anchor to keep it in place

Guideline #1: Don't be a jerk.

Beginning Climbers
Post a Reply to "Offset Top Rope Anchor"

Log In to Reply

Join the Community

Create your FREE account today!
Already have an account? Login to close this notice.

Get Started.