Some Thoughts About Rope Diameter And Durability

I've coreshot or significantly nicked several ropes this fall and winter. Initially it really pissed me off. I felt like I wasted a lot of money (in one case I truly feel like I did) on gear that really isn't worth buying. Mostly though, it's helped me think about what type of rope is appropriate for daily use and when I need to be really careful about protecting my rope so that it lasts as long as possible.

First, I'm going to share a few of my experiences and some comparisons between Sterling and Mammut, the two rope manufacturers that I've used the most. Then, at the end I'll share a few of my conclusions that might help guide readers when making a decision about rope purchases

Some experiences and a few comparisons

ALL of the ropes that I've had in the 9.0mm range have not been durable. This should come as no surprise to anyone at all. However, the complete and utter lack of durability of some of these ropes leaves me wondering whether they should be sold at all. It seems distinctly possible a rope this skinny could sever during a big fall or while sliding over an edge. The Sterling Nano is the least durable rope I've ever owned. Don't get me wrong, Sterling produces some nice ropes, but many of their Fusion series ropes are just too soft. I've had two Nano's so far, and both received coreshots and significant wear during what I would consider normal use. I nearly severed one during a rappel this winter. It was the rope's first use, and it left me wondering whether I should even bother using the rope again. I had one Mammut Serenity 8.9 mm as well. It has held up slightly better, but it has countless nicks in it's sheath. The 8.9mm Serenity feels slightly thicker than the 9.2mm Nano. Either way, a rope this skinny isn't going to hold up well for most people. I've also heard (hearsay only) that the purple Nano is actually built differently than their other colors and is more durable. I'm not sure what that means, but it might be worth buying a purple Nano if you decide to pull that trigger.

Stepping up in diameter, I've used both the Mammut Revelation 9.2 and the Sterling Ion 9.4. Both of these ropes feel far more durable than their skinny brethren. Each of these ropes has lasted nearly a year with light use (whereas a single long day or a single trip will trash the Serenity or Nano). The Revelation was actually one of my favorite ropes, and I used it for nearly an entire winter season while cleaning and working routes in the Hell Hole during the 2010-2011 winter.

Many nicks in the sheath of an 8.9 mm Mammut Serenity

The next step up in diameter durability for most manufacturers is to the 9.5-9.8 millimeter range. I've used both the Mammut Infinity 9.5, my favorite rope thus far, and the Sterling Velocity 9.8. While I've had good luck in the past with both ropes, This fall I nicked or coreshot two Sterling Velocity ropes rather quickly. One was absolutely my fault, yet I was still surprised by how quickly it happened, The other incident , during the rope's first use, involved several nicks during normal toprope wear and tear that a rope of this diameter should hold up to. Both were less than three weeks into my ownership of the rope, and with less than a week's worth of climbing on each.

I've only really used one rope over 10mm in diameter - a Sterling Marathon Pro. It's a burly rope and I've had several of them. If used occasionally they'll last several years before they begin shedding lots of fuzz from the sheath. The Mammut ropes over 10mm always felt a bit too stiff to manage, especially once they begin to freeze.

Conclusions

Here are some of the conclusions I've drawn about ropes over the past few years.

•  The skinniest single ropes are too skinny for daily use, and probably too skinny for any sort of rock or alpine use. I know there are people that will disagree with this, but when your safety and the success of a big alpine trip rely having a full-length intact rope, sizing up just a bit seems like a wise decision. The weight difference between a 60-meter Sterling Nano and a Sterling Ion is only 240 grams, just slightly more than half a pound, yet the durability of the Ion is much, much greater. In addition, you'll replace ropes less often meaning you'll save money in the long run.
• Mammut ropes always feel fatter than Sterling ropes. The Mammut 8.9 feels fatter than the Sterling 9.2. The Mammut 9.2 feels fatter than the Sterling 9.4, and the Mammut 9.5 feels like the Sterling 9.8.
• Mammut ropes generally feel stiffer than the comparable (see my conclusion above) Sterling rope.
• Mammut ropes always feel short. Sterling ropes always seem generously long. In fact, if you're going to buy a Mammut rope you might consider buying a 70-meter model. Many of the Mammut ropes I've had end up being as much as 10 meters short by the end of their usable life. Mammut attributes this to shrinkage, I'm not sure I buy this explanation and will hold off on my own explanations.
• I've had really good luck with the Mammut Revelation 9.2, the Mammut Infinity 9.5, the Sterling Ion 9.4 and the Sterling Marathon 10.1.
• The Sterling Nano 9.2 is, in my opinion, utter garbage. Not only is it expensive, it's the least durable rope I've ever owned and I'll never buy another one.
• I've had several Sterling Evolution Velocity 9.8 ropes with varying degrees of success. If you buy one of these ropes you might try to baby it at first, as this rope seems to stiffen after a few weeks of use, and then feels a bit more durable. Initially this is a soft rope that handles nicely but also nicks easily. Kind of a crapshoot if you ask me.
• The Sterling Marathon 10.1 and Mammut Infinty 9.5 are both good choices for every day rock climbing use, but won't slide easily through an ATC Guide or Reverso in autoblock mode, especially once they've been used for a while. Consider using a Kong Gigi as an autoblocking belay device instead.
• Dry treatment is fleeting. I've been able to use non-dry ropes for most winter days. If it's really going to be wet I'll grab a dry rope. This way, I can preserve the dry-treated rope for really wet days.

I hope this helps you during your next rope purchase.