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Smallest diameter rope for ascending

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No Face · · Yubaba's bathhouse · Joined Jul 2020 · Points: 1

What is the smallest diameter rope you can use for ascending? I'm talking about either using ascenders to ascend in free space , or top rope soloing with a petzl basic + micro. Obv a gri gri can't really go lower than about 8.9 mm... But with an alpine ATC you can descend a single fixed static rope much thinner. 

So what's the min diameter for going up?

Christian Hesch · · Morro Bay · Joined Aug 2017 · Points: 54

IIRC, I think I fix-n-followed freeblast on a 7.1, mostly microtrax but I def jugged at least a couple pitches, and it worked fine… but I wouldn’t recommend it. 8.5 opera is great IF you know for certain there are no spots for rope rub, but otherwise 9.0 is nice for the warm fuzzies.

Honestly it’s difficult to answer with clarity as I’m not really sure what you’re looking to do (TRS, fix-n-follow a multi, trail on a wall for 3rd partner…???)

Christopher Chu · · San Francisco, CA · Joined Apr 2011 · Points: 40

Petzl ascenders and MicroTrax are rated down to 8mm ropes.  NanoTrax is 7mm  .  I'll second Christian's recommendation for the Beal Opera at 8.5mm given it's unicore, fits in a Grigri (8.5mm minimum), dynamic, and single rated.  If you're only using it to ascend though, I guess you can go with ice lines or (semi) statics that are within the ascender ratings (YGD).

Jake Messner · · NorCal · Joined Jan 2020 · Points: 184
Christian Hesch wrote:

IIRC, I think I fix-n-followed freeblast on a 7.1

Don't let this guy bring up you El Cap while ascending shoe lace ropes behind him! 

Kevin DeWeese · · Oakland, Ca · Joined Jan 2007 · Points: 981
No Face wrote:

What is the smallest diameter rope you can use for ascending? I'm talking about either using ascenders to ascend in free space , or top rope soloing with a petzl basic + micro.

You're thinking about the wrong part of the equation.

For diameter, you can effectively ascend a 6mm rope (I have) with mechanical ascenders, but you don't want to. 

It's the "don't want to" that's the correct part of the equation. As the diameter goes down, the protection from the rope being sawed in half by edges and other aspects of a rope in a fight with rough rock goes up exponentially. Remember that ascending pulls the line taught and lowers the threshold where force/friction/stress can cause a catastrophic failure. Yes, a free hanging jug avoids this but it's far and few between where you get a free hang all the way to the bolts. And even though tr solo falls aren't high force, they still produce higher forces than simply ascending the rope.  

Since ascending is rough on the rope both from the rock and the ascender's teeth, the single point of the rope being between you and an early grave means that your main concern is, "What's the smallest diameter of rope you're willing to trust your life to while it's being abused in a high consequence situation?"

ryan climbs sometimes · · MT · Joined Oct 2022 · Points: 72

Iv done 7mm , can’t recommend 

Danny Bell · · Buford, GA · Joined Sep 2019 · Points: 325
No Face wrote:

What is the smallest diameter rope you can use for ascending? I'm talking about either using ascenders to ascend in free space , or top rope soloing with a petzl basic + micro. Obv a gri gri can't really go lower than about 8.9 mm... But with an alpine ATC you can descend a single fixed static rope much thinner. 

So what's the min diameter for going up?

I whipped on a 8mm with a gri gri while LRS. The gri gri caught and rope held, but I wouldn't recommend. I realized later on that was stupid and now I stick to a 9.1

The Muddyboots · · Unknown Hometown · Joined May 2020 · Points: 0

I use 1/2” static lines in pairs at work and a ton of 11mm NFPA static line too, I do mountain travel with a 9mm. and I grew up cragging on 11mm dynamic.

What I really want is 11mm plus when it’s carrying me and 9mm minus when I’m carrying it. So what I really need is magic rope…

With modern materials and lengths sub 9.5 makes a lot of sense, but 8mm is a little to spicy. For walls, I like big ropes and I can not lie…

Sam The Average Climber · · San Diego · Joined Nov 2021 · Points: 0

Petzl pur line? Thoughts?

Ricky Harline · · Angel's Camp, CA · Joined Nov 2016 · Points: 142
Sam The Average Climber wrote:

Petzl pur line? Thoughts?

Would be better than any other similarly sized cord. You couldn't pay me to ascend mine, however. 

People do it. Colin Haley fixes his and then rappels them and uses them to get back to his high point. That's a hard pass from me, dawg. 

Guideline #1: Don't be a jerk.

Big Wall and Aid Climbing
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