Tuesday, January 4, 2011

Anchor Installment #1 - Trees

This installment depicts a variety of ways to anchor off a tree.

Keep in mind, that the goal for all anchors is "SERENE".

  • S - Strong (or Solid) - The stronger the better
  • E - Equalized - Anchors should be constructed so that each component of the anchor carries an equal amount of the load
  • R - Redundant - Anchors should consist of multiple components in case one or more components fail
  • E - Efficient - Anchors should be as simple and timely as possible without giving up any of the other SERENE qualities
  • NE - No Extension - Anchors should be built so that if one or more of the components fail the remaining components won't be shock loaded 
Solid, Equalized, Redundant, Efficient, and No Extension. Above all else, anchors must be Solid. Complete anchor failure often means death to you, your partner or both. Get proper training and practice anchors on the ground before you go out and try them in a climbing setting.

To anchor off a tree, there are a few rules of thumb you might want to keep in mind. These include (1) make sure the tree is alive, (2) keep the anchor as low as possible, (3) be sure it's at least as large as your thigh, and (4) be sure it's firmly rooted in dirt (not 4" of dirt on top of solid rock!). Before you commit yourself and your partner/s to a tree be sure to push on it and make sure it doesn't move or break. Be careful not to fall over the edge if it gives way while you're pushing it! Also, check for sap and any sharp rocks that might be near the tree. You can use an old piece of carpet (or your partners favorite sweatshirt) to protect the rope, slings or tree.

Note - if you're Top Roping off a tree anchor, add another carabiner (preferably a locker) at the master point. These pics only show 1 for clarity. Also, when tying in with a clove hitch, be sure to orient the "load strand" toward the back of the 'biner for maximum strength. And don't forget to lock the 'biner and tighten the clove hitch before you lean into it.

Tools needed: A couple of locking 'biners, slings, and a rope.

Option #1 - Double Length Sling: Wrap a double length sling around the tree and close it with a locker. This is OK. It's Strong (assuming it meets the "rules of thumb" above), it's Efficient, it's Equalized but it's NOT redundant. I would add a 2nd double length sling if I had one. You can also girth hitch two single length slings together. 

Option #2 - Single Length Sling: I guess this would work in a pinch if that's all you had. But it's bad for all kinds of reasons. It cross loads the 'biner, it's high on the tree (because it was too short to go around the base), and it's not redundant. Better add another sling.

Close up showing the 3-way cross loading of the 'biner. This dramatically reduces the strength of the 'biner. If you forgot to lock the gate, the 'biner could blow apart in a hard fall. Not good.

Option #3 - Add a 2nd Single Length Sling: Again, this would probably work in a pinch but it's still got some serious issues. It's not redundant and it has a "pulley effect" the way it's threaded through the 'biner. The pulley effect puts unnecessary force on the anchor.

Option #4 - 2 Single Length Slings Girth Hitched: These 2 slings are girth hitched together. Much better but still not redundant and the slings put a bit of cross loading on the 'biner.
Option #5 - 2 Slings, Crossed Over: To remove the cross loading by the slings, simply cross over the slings (like you were tying your shoes). Still not redundant but much better. If you had enough slack in the end of the slings you could tie them in an overhand knot and make them redundant.

Option #6 -Open Sling or Cordellete: If you have 1" tubular webbing or a cordellete, you can simply open it up and tie it around the tree. Use a water knot on the webbing and an overhand knot in the Cordellete. I recommend 8 millimeter Cord or 1" tubular webbing for this purpose. It's rated at over 3,000 lbs. Note - Don't use 1/2" webbing. It's only rated for 1,000 lbs. - which sound like a lot but a top rope fall could easily generate 1,000 lbs. of force. This setup is good but still not redundant. If you had a couple more slings, you could add them both.

Option #7 - Doubled Cordellete: Finally some redundancy! This meets all the SERENE requirements and rules of thumb. It's quick and simple. Just wrap the Cordellete (or 1" tubular webbing) around the tree twice and tie an overhand knot or Figure 8 knot in the end. If any single line were cut, the whole thing would hold together.

Option #8 - Rope: Take a BIG bight of rope, wrap it around the tree and tie it into a bowline. Don't know how to tie a bowline? Better learn before you climb in an area that requires tree or rock anchors. Practice it in your backyard and have the neighbor kids pull test it before you head out to the rocks.

Close up of the bowline knot. Note - this is turned around 180 degrees from the pic above (sorry for the confusion!). This setup would be even better if it was tightened and had a stopper knot tied behind the loose end. This setup is efficient but uses a LOT of rope. To get a redundant master point (aka power point) in the rope, simply tie an overhand or Figure 8 knot in both ends of the rope between you and the bowline knot.

Option #9 - Tree Wrap: So what do you do if it's late, you're tired and can't remember how to tie a bowline in the dark (much less remember your own name)? Just walk around the tree, tie a Figure 8 knot in the end of the rope and clip it back into your belay loop or harness. I know what you're thinking, "But it's NOT redundant!" Well it doesn't need to be redundant, it's ROPE! The rope can literally hold you, your partner AND your truck without much trouble. If you have enough rope, you can add a Master Point by bringing both ends together between you and the tree and tying a Figure 8 or overhand knot. Assuming you chose this scenario because you can barely remember your name (or were nearly out of rope) you can also belay directly off your harness. Often times, simple is best.

Stay safe and have fun!


Sunday, January 2, 2011

Anchor Installment #3 - Bolts

It was raining today, so I spent a little time creating a blog that demonstrates some options to set up bolted anchors. NOTE - Internet research is no substitute for proper instruction. Be to take a class, read books, talk to other climbers, and get out and practice your anchors!

In an effort to help remember how to properly set anchors, many people use the acronym "SERENE".

  • S - Strong (or Solid) - The stronger the better
  • E - Equalized - Anchors should be constructed so that each component of the anchor carries an equal amount of the load
  • R - Redundant - Anchors should consist of multiple components in case one or more components fail
  • E - Efficient - Anchors should be as simple and timely as possible without giving up any of the other SERENE qualities
  • NE - No Extension - Anchors should be built so that if one or more of the components fail the remaining components won't be shock loaded 
I've included some typical scenarios below. 

1. Two Solid Bolts Evenly Spaced: This bolted setup is one of the simplest to build and is quite common at most crags. All you need is two equal length slings and 4 carabiners. At least 2 of them should be "lockers". At the very least, be sure there is at least one locker on the master point (the point where the rope goes through).

2 - Two Solid Bolts Slightly Offset: If the bolts are slightly off-set you can add an overhand knot or a figure 8 knot into the longer sling. This should equalize the anchor point so the weight is evenly distributed on both slings.

3 - Two Solid Bolts Slightly Offset: If the offset is only minor, you can add a couple wraps on the carabiner to the longer sling. Make the wraps on the locker if you have a choice.

4 - Two old bolts & 1 new bolt: This scenario tends to occur in back country settings where the bolts have to be hand drilled. Rather than pull the two old bolts and replace them, the bolt replacer has chosen to simply add a single new bolt. You could simply clip only 2 bolts (the new one and the best looking of the old ones) but it's better to add both old bolts into the system and having them equalized. This rigging uses a single length runner on the old bolts with an overhand knot in the middle of it. In order to be redundant on the old bolts, be sure to clip into both loops so if either old bolt pulls out, there will be no "Extension". This rigging uses 4 carabiners, 1 shoulder length sling and one double length sling. Pretty efficient and most climbers have at least one double and one shoulder length sling. Take your time adjusting the knots so that everything is equalized. This setup could be slightly better by extending the left leg of the blue sling so that more of the weight is taken up by the new bolt.

5 - Two old bolts and 1 new bolt: This is the same bolt arrangement as above but rigged with a 20' cordellete instead. Note that this rigging uses one less carabiner (but you have to remember to bring a cordellete). Weight the system with body weight then make any final adjustments before you use it. Some people worry about whether they should clip the bolts or the chain or chain links attached to the bolts. The answer is that it usually doesn't matter. Most of the metal hardware you run into at the crags is stronger than the rope or sling that's attached to it. If you have any doubts, then just clip the bolts. WARNING - Sometimes rap anchors are extended with "fixed slings". Never trust fixed slings for an anchor and always clip the bolts. Better yet, bring a knife and cut the old fixed slings off and replace them with chain. 

 6 - Two solid bolts, setback from the edge: Many times you need additional length to get over to the edge. The cordellete is your best option in this case. This is super quick and easy to untie. Use a Figure 8 or an overhand knot in the end with the master point. Add at least one locker and one non-locker (with gates opposed) to the master point.

7 - Two Solid Bolts, set way back from the edge: Sometimes you need even more length. With a 20' cordelette, you can untie it and extend it quite a distance. The bolt ends have Figure 8 Knots in them. Be sure to use 8 millimeter nylon cord since you have only 1 strand going to each bolt. At the master point, you'll need to tie a BHK, or Big Honkin' Knot. This is simply an overhand knot with one side folded back. Google "BHK Climbing Knot" and you'll find info. on how to tie these.


8 - Two Solid Bolts: This is the same bolt arrangement as before but the BHK has been moved up to bring the master point closer to the bolts. Using the BHK you can quickly move the master point further or closer to the anchor. The BHK results in an extra "leftover" loop. If it's short leave it hanging free. If it's long, you can bring it up and clip it to one of the carabiners on the bolts or tie it in an overhand knot on one of the other cords.