I used this method from SuperTopo to rope solo a 5.8 crack route today. A few things to make clear with this approach:
- You’re not tied into the rope by a figure 8. Instead, you’re fastened to it with a Micro Traxion pulley. As you climb, the rope automatically feeds down through the pulley because it’s weighted with a water bottle (or a pair of approach shoes, or something else). The teeth in the Micro Traxion prevent movement of the rope in the opposite direction, thereby arresting a fall.
- The rope is fixed at the top. An elegant way to do this is with a bunny ear figure 8 knot tied in the middle of the rope, and two locking carabiners.
- The Micro Traxion is your fall-catcher, but you’re backed up by clipping into knots (alpine butterflies) in the other strand. If your Micro Traxion were to fail or the strand on that side broke, those knots would limit your fall to the interval between them. Clipping in and out of those knots can be tricky, but kind of gives a feel for climbing on lead and having to place gear with one hand.
- Static vs. dynamic ropes. A lot of talk about how a static rope works better for rope soloing. I used a dynamic rope, my Mammut Infinity. The stretch was a little annoying, but overall didn’t seem to compromise anything.
- Does the Micro Traxion shred the rope? Many people use them to rope solo, quite often two of them (one is primary, the other is backup rather than clipping into knots). A discussion on Mountain Project seems to conclude that only large falls of 5 kn or more would cause rope damage. So check that the rope is feeding through to minimize potential fall factors.
- With the SuperTopo method, the strand with the backup knots can get stuck in cracks. This got annoying, so I’m looking into just using a secondary device on the other strand. Another climber mentioned the Camp Lift ascender. This is a toothless device, which, depending on whom you ask, has a lower potential to damage the rope sheath. One thing nice about it is that it allows movement of the rope in both directions, but will lock up if the movement is too rapid.
Overall, I really enjoyed rope soloing. With a partner, you forget how much time you spend just belaying. In a few hours I got 8 laps in, and got better at hand jams. This is definitely a great way to get mileage in alone.