Shortening a sling - do the twist
Sometime when rigging an anchor, it’s helpful to shorten a sling by an inch or so to get better equalization. While tying an overhand knot in the sling works great if you need to shorten a sling a lot, that trick does not work so well when all you need is to shorten a runner by a few centimeters. Instead try this simple tricks: just add twists to the sling. This will shorten a sling a cm or so with each or twist, allowing you to fine tune the runner length.
Shortening a sling - multiple wraps on a biner
Sometimes when rigging anchors, you may need to shorten a runner by an inch or two. Here’s a very quick way to do it: Just make a few extra wraps around a carabiner. Each wrap shortens the runner by a few cm, helping you to fine-tune the length of the runner.
This tip is from: Rock Climbing Anchors: A Comprehensive Guide, by Craig Luebben, The Mountaineers Books, 2007
Try the Garda Knot for quick hauling
When you need to quickly haul a pack or small haulbag, instead of doing the forearm-flaming hand-over-hand haul, tie a Garda knot in the haul line. The Garda knot is a one-directional, self-locking knot that lets you haul, but relax your grip when you tire. It will also prevent your accidentally dropping the pack.
To tie, simply rig the rope through two carabiners clipped to an anchor sling. Ideally, use identical oval carabiners, which will allow the smoothest operation. To haul the pack, simultaneously pull up on the pack side of the haul rope and down on the other side of the rope (figure 1). Locking the knot is simple: just let go.
This tip is from From Rock and Ice magazine
Slinging a boulder for an anchor - two cautions
A common anchor on alpine routes is the simple sling around a boulder or rock spike. Even though the boulder itself may be super solid, there are some things to watch for when using this method.
1) Check the boulder carefully all the way around for any sharp edges. A new sling that can hold 20kN can cut very easily under tension combined with the sharp edge of rock or a crystal.
2) A short sling around a large boulder may make a wide angle in the sling that put a larger-than-ideal load on the sling material. (An angle of 90 degrees or less is the rule of thumb, and 60 degrees or less is ideal). Solution: Use a longer sling to make the anchor angle smaller. The diagram below shows how a small change in sling angle and greatly increase the forces on your anchor.
The diagram is from the excellent book The Complete Guide to Climbing and Mountaineering by Pete Hill.
Two common mistakes in building rock anchors
The first step in anchor building: After securing yourself with a good piece or two of pro, take a few deep breaths and 30 seconds to look around and review ALL the possibilities for gear placement. Calmly “expanding your vision” usually turns up more (and better) anchor options than myopically plugging gear in the first crack you see.
Place gear high
One of the most common mistakes in anchor building is placing pro too low. If you place gear at chest level, after equalizing everything, the master point will probably be below your waist - not good if you want to stand to belay. Placing gear at head level and up, when possible, offers more options in your stance and is generally better.
“Wrap 3, pull 2” - about the strongest anchor you can build
Long a preferred method with rescue teams and others who need a super strong anchor, this anchor can also be useful for recreational climbers.
As it takes a few minutes to tie, it’s not really feasible to use it regularly as part of snow or rock pro. However, it can be useful when setting up top ropes in an instructional setting, making a rappel anchor, or pulling your car out of a ditch. All you need is a long (10+ feet) length of webbing. (While 1” tubular webbing is not always the best choice for actual climbing, in this case it may make sense because of it’s extra strength.)
To make this anchor, make three wraps with the webbing around a large solid object (in this case a tree) and then tie the free ends in a water knot with at least 2 inches of tail on each side of the knot. Now, pull the two strands of the webbing that do not have the knot in them, leaving the actual knot against the tree. The knot, normally the weakest part, is isolated by the friction against the tree and has minimal load on it. Four strands of webbing share the remaining load. This is super strong, and given the right circumstances, can be a good anchor trick to know.
Diagram is from Freedom of the Hills, 7th edition, The Mountaineers
Cordelettes - not as good as you thought
New anchor research - the sliding X is back!
The cordelette anchor system used by many of us may not be as great as we thought. John Long, author of “Climbing Anchors” and “More Climbing Anchors”, is doing extensive research on anchors for his new anchor book, soon to be published. (Long, through these books, pretty much single-handedly established the cordelette as a standard in the US.)
After lots of drop tests and force measurements for his new book, Long has found that the cordelette does NOT really equalize placements. Even in perfect alignment, when the cordelette is tied to multiple placements and the anchor is then weighted, most of the force goes on the smallest leg of the cord.
There is an extensive discussion on the web about new anchor systems. The thread is called: “Improved sliding X: is it really safer?”
John Long himself has made many posts here about his findings. (The fact that the leading proponent of the cordelette is now saying that it doesn’t really work certainly should grab your attention!)
We’ll have to wait until the book is published for the complete results. For any leaders involved in anchor instruction during the coming spring and summer climbing season, having a look at this discussion thread and learning something about the new systems would probably be a good idea. This idea has already been introduced in the Advanced Rock program.
- Some version of the sliding x knot is preferred for true equalization. (Yes, doing this with more than two points of protection is tricky, but that is rarely a problem in alpine climbing.)
- Tie an overhand knot in one or both arms of the sliding x to limit possible extension.
- So-called “shock loading” is really not a problem on most anchors, provided the slip is about 6 inches of less.
- A cordelette anchor is only suitable when anchor placements are one very strong and to next to each other horizontally. (Such as a bolted sport climbing anchor.)
The importance of being EARNEST - a mnemonic for anchors
When building anchors on rock or snow, keep in mind that the ideal anchor is EARNEST. You won’t be able to do this all the time, but it’s what you are striving for. (This is a slightly more encompassing “anchor” mnemonic than RENE or SRENE, which you may have also heard.)
Equalized. Through actual equalization (sliding X) or static equalization (cordelette), all anchor components share the load more or less equally.
Angles Appropriate. To minimize forces placed on gear, ideally all angles between placements are 60 degrees or less.
Redundant. If any one component of the anchor were to fail, the entire anchor will not fail.
No Extension. If an anchor component were to fail, the anchor will not extend too far, possibly shock loading the remaining components.
Strong. The individual placements are as good as can be, given available gear and rock features or snow quality. (After you build the anchor, give it a good shake to be sure the pieces hold.)
Timely. A rock solid anchor can be a bad choice if it takes too long or too much gear to build. Better to go for a slightly lower quality anchor if it takes a lot less time to construct. Note - “too long” can vary widely depending on team skill, route difficulty, and how many hours to nightfall!