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When Tommy Caldwell or Mayan Smith-Gobat work a free climb high on El Capitan, the crux may be finding a belayer willing to put in days of duty in an isolated and exposed location. Often, the solution is to go alone, rehearsing the key pitches by solo toproping. Whether you’re an active first ascensionist or just want to do some laps after work without a partner, solo toproping is a handy technique to add to your repertoire.
Though there are several methods, all share a couple of aspects: Before ascending, the climber fixes one or two ropes to an anchor above the pitch, and then climbs self-belayed by ascenders or progress-capture pulleys clipped to the rope or ropes. (A progress-capture pulley is usually used for hauling a load—it allows the rope to roll smoothly in one direction but stops the rope if it’s pulled in the other direction.)
Solo-toproping techniques vary mainly in their back-up methods. And you must be backed up—never depend on a single device. Some climbers hang a second rope alongside the first and clip into bights pre-tied in the backup rope in case the primary rope or belay device fails. Others climb with two different devices clipped into two separate ropes. (This is the method recommended by Petzl, which makes the most popular devices used for this technique.*) Top climbers such as Caldwell, Steph Davis, and Matt Samet prefer the method described here: two devices on a single static rope.
Here’s how to do it:
Anchor the rope.
For simplicity’s sake, we’ll assume you’re toproping a single-pitch climb. Ideally, your rope should be clipped to a solid anchor below the top of the cliff, so the rope does not rub over any edges. If you’re setting up the toprope from above, build a backup anchor above the cliff, and then set your primary anchor below the lip.
In this method, a static rope is safest and easiest to use. Safest because it won’t bounce much under load; this reduces dangerous wear. Easiest because the devices will track well along a static rope as you move. Climbers experienced with this method recommend a 10mm or thicker static rope for security and rope longevity. Note: If you’re using a second rope as a backup, this second rope must be dynamic, in order to absorb the shock you’ll generate if your primary system fails.
After returning to the bottom of the climb, coil the extra rope and let it hang above the ground, or clip a water bottle or other weight at the bottom of the rope—this will add a little tension, helping your self-belay system slide smoothly up the rope at the start of the pitch.
Set up your self-belay.
Although many different ascenders and progress-capture pulleys can be used, most climbers using this method prefer the Petzl Mini Traxion or Petzl Microcender, or a combination of the two. Petzl recommends always using two different devices to maximize the benefit of the backup.
Following the manufacturer’s instructions, attach the two devices to the rope, one above the other. Make sure the devices’ cams are properly locked onto the rope—inattention at this step is the most common cause of self-belay failure.
Clip both devices to your belay loop. You must use either oval locking carabiners or anti-cross-loading locking biners.
The top device is your primary self-belay. To keep it in the ideal position for braking (and separate it from the other device), connect the top device to a chest harness, a pair of slings draped over each shoulder so they cross in the middle, or a single sling. (Caldwell drapes a headlamp strap around his neck and clips this to his device.) Unlike a true chest harness, this system is not load bearing, but simply holds the device in position. Use a bit of webbing or an adjustable strap to connect this system to the top ascender, using the same clip-in hole as the locking biner on the device. Make sure that no cords or straps from your clothing or pack can interfere with your self-belay devices.
Before starting up the pitch, test both devices to make sure they will lock properly under weight. Gently bounce-test the system in a safe position at the base, and make sure the devices don’t interfere with each other. If the bottom device bumps into the top device, extend the top device with a quickdraw, using locking carabiners on each end of the draw. If you do this, make sure your chest harness is still comfortable and keeps the top device positioned upright on the rope.
You may need to push the devices along at the start of the pitch, but soon the two should slide up the rope as you climb. If you have clipped intermediate anchors or protection points along the route (on an overhanging climb, for example), never climb above these pieces without unclipping the rope from them first.
Escape the system.
There are at least two situations where you will need to escape from your self-belay system. At the top of the pitch, you’ll need to unclip from the devices in order to descend. Less commonly, you may need to escape from the system if you can’t do a move or otherwise run into trouble.
When you reach the top of the climb, use slings or personal tethers to clip into the anchor. Be careful not to climb so high that your self-belay system bumps into the anchor—this will make it difficult to unweight the devices and escape from the system. It may help to clip long slings to the anchor before you climb, and then clip into these slings when you reach the top, so you are hanging well below the anchor.
Once you are securely anchored, remove both devices from the now-unweighted static rope. Attach your rappel device to the rope, and rappel to the base of the climb. If you must climb past the primary anchor to retrieve your backup anchor, first clean the primary anchor and pull any slack in the rope above you through the ascenders, before you start climbing again. Note: Never climb on a slack static rope using the toprope self-belay system. A fall onto a slack static rope could injure you (even fatally) or cause the system to fail.
You also need a way to get up or down if you can’t do a move. This means you’ll need to unweight the self-belay devices mid-pitch, and then either rappel or ascend the rope. To prepare for this, always carry some extra gear on your harness: an assisted-braking belay/rappel device (Grigri, Cinch, etc.), a backup ascender such as a Petzl Tibloc or Wild Country Ropeman, and a double-length sling to use as a foot loop for ascending the rope or unweighting the devices at your waist. The various techniques for escaping the system using these devices are beyond the scope of this article, but whichever method you use, practice while you’re still on the ground.
Stay alert whenever you reattach your self-belay system—when you’re ready to do another lap on a route, for example. This is where most mistakes happen. You must be sure the cams on each ascender are properly engaging the rope before climbing or weighting the system again.
*Petzl has published an extensive analysis of self-belay toproping, including its recommended method and various alternatives. Google “Petzl self belay.”