Rope Choice?

[Zenolith]

I need to make a choice. I have one 9.8X60 dry that I use for everything. Most of my climbing is alpine snow and ice. I am getting into steeper and more mixed alpine stuff and want to do more water ice. My old 8.5 glacier rope is being retired so I was thinking of getting an 8-9 mm X60 dry for using on WI and on alpine climbs where two ropes are needed. I thought I'd get a 30m glacier rope for ski mtneering and volcanos. So, does anyone have thoughts on coupling an 8.5X60 with a 9.8X60? Is that a bad idea? I'm asking b/c I can't really afford a pair of ice ropes right now.

[Lambone]

It'll work, just makes for a heavier set up...

Be sure to clip them independently.

[Zenolith]

"Be sure to clip them independently."

Why is that? B/c they have diff stretch?

[Ibex]

quote:

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Originally posted by Zenolith:

"Be sure to clip them independently."

Why is that? B/c they have diff stretch?

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Sort of....

It gets back to the whole double ropes vs. twin ropes concept.

Double ropes= ropes that are tested one strand at a time by UIAA and are intended to be clipped independently to pro

Twin ropes= usually thinner, stretchier ropes that are tested in pairs, and are meant for two strands to be simulaneously loaded in a fall (ie. clip both ropes into every piece of pro). Note also this assumes that both ropes are identical, and will respond the same to loading.

There is much debate, but little hard data, published concluding that if you clip 2 DOUBLE ropes to the same piece of pro that because they are slightly thicker and less stretchy/dynamic that it will increase the force on a piece of pro. With the obvious concern to marginal pro, ice screws, etc...

Then you have the mitigating factors of dynamic belays, screamers, low impact force ropes, etc....

So some will argue to the end that if you clip 2 DOUBLE ropes into a single piece of pro, you are in for a hard catch, and possibly pulling out your pro. Others will argue that the difference between double and twin ropes, when clipped through the same piece (use two separate biners when possible to avoid rubbing b/w them) is pretty academic.

This latter case is similar (but slightly more extreme) to what was cautioned against above, using non-twin ropes hooked into one piece of gear. The concern is that the impact forces are too high because the ropes are engineered to have a certain amount of stretch (and shock absorbtion) by themselves, not in pairs.

Do some reading and decide for yourself what you are comfortable with. Regardless of what side of the double vs. twin arguement you fall on, you should be safe using a half rope (one designed for double rope technique) and a full single rope, as long as you clip them to separate pieces of gear.

Cheers

Shawn

[Smoker]

If your gonna climb on a single line, fine

and if your gonna climb on doubles fine

But if your gonna climb on a single and a double and use them as a double rope system your taking unneeded risk. better to climb on the single and trail the double. using it to rap.

Smoker

[snafflehound]

quote:

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But if your gonna climb on a single and a double and use them as a double rope system your taking unneeded risk

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smoker, what's the downside? S