Twin vs Single Ropes?

I will be traveling and climbing all over Europe next year with my gf. I was planning on only bringing one rope, but after doing some research I see that many routes require 2 ropes to descend. Being as we will be living out of our backpacks for 6 to 9 months weight and space is very important. My new thought is to bring twin ropes and each carry one.

Good idea? Any reasons not to do this? Has anyone done a trip like this and have any suggestions? I greatly appriceiate any info or suggestions!

Thanks!

I have become a big fan of 70m doubles on everything but the most straightforward climbs. Once you're used to them they are easy to manage and they make descents a no-brainer in a lot of cases, especially if you're trying to figure out pitch lengths in a handwritten Czech guidebook.

I am also a big fan of twin 70s on everything except the "trade routes" with a walk off. It's nice to always have two ropes and
weight is not an issue.

The other nice thing about double (not twins) ropes is that you needn't clip both strands into each piece. You can alternate clipping the ropes, which, if the route wanders, you will lower rope drag. It is nice that the second doesn't need to trail a second rope for descent purposes, as the leader is using both. Less chance for a rope to get stuck.

Is there a difference between the actual ropes for twin vs double? Is one stronger than the other?

Since weight is import my thought is to use a twin system (both ropes through each piece of gear) on straight forward climbs including sport, and to use a doubles system for alpine wandering routes. This way we only need two ropes for any type of climbing we might do.

Generally from what I understand, twins must be clipped in pairs to each piece, whereas doubles do not need to be. Doubles can be clipped individually as circumstances dictate.

So doubles could be used as twins, but twins should not be used as doubles?

If space and weight were not issues, I think the choice of doubles would be a no-brainer.

Doubles have a lot of advantages over twins. But in this case, twins may be the way to go.

A brief search suggests the following relative weights:

(1) single ropes: the lightest (10 - 10.2 mm) are around 61 - 64 grams per meter.
(1/2) half ropes: around 42 - 48 grams per meter.
(oo) twin ropes: around 37 grams per meter.

So a pair of twin ropes will be about 14 g/m heavier than the lightest single rope (a pair of doubles will be about 24 g/m heavier). That is a total increase in weight of about 23%

Note also that 5 mm cord weighs in at about 20 g/m, so even using a single rope with a 5 mm rip cord is heavier than the twins, and is on par with a pair of doubles.

Personally, I'm biased toward doubles (because of their versatility), and would still recommend them if you can bear the weight. But if weight is your primary concern, then I think twins are a good idea.

jmac wrote:So doubles could be used as twins, but twins should not be used as doubles?

It depends on the actual rope. Some ropes are designed only to be used as twins (oo). Others are designed only to be used as doubles (1/2). Some are designed for both, and some are even designed to be used as singles (1) also.

Clipping both doubles (1/2) as twins results in high impact loads. Generally speaking, a single twin rope (oo) does not provide enough strength to catch a falling climber, especially if loaded over an edge.

Technically both twin and half ropes are double rope systems. For clarity twin ropes necessitate the clipping of both ropes into every piece of protection. Half ropes (commonly erroneously called double ropes) are designed to be alternatively clipped to each piece of protection.

Twin ropes are individually designed with a low impact rating and therefore a quite stretchy, needing to be used together to provide the correct amount of energy absorption. They are also not rated for falls on an individual strand. Bottom line if you use twins as half ropes you may take a very long ride.

Half ropes have higher impact ratings, given that they are essentially operating as a single line during a fall. If they are clipped together as twin rope system they can create a much higher level of impact, potentially ripping out your gear.

Thus, twin ropes should not be used in a half ropes, and half ropes should should not be used as twins.

With all that said, several manufactures now make ropes that are rated both as half and twins - a bit of compromise on both ends. I own such a system from Meteolius and highly recommend it, having the best of both worlds. The PMI Verglas is also another option.

Thanks Everyone! This has been very helpful. I keep thinking of more questions though.

When belaying doubles (half ropes) how do handle feeding the ropes at different rates? I assume for both twin and half you thread the ATC like you are rappelling? Guess I’ll have to leave the Gregry at home. Hey that will justify some of the extra total weight!

Only specific diameter double ropes can be used as both double or twin set up - Also known as Half Ropes - as denoted on the tag on the ends. Something to do with surface area while clipped together in one carabiner - or some tech mumbo jumbo that I don't understand...

Twin Ropes - Super skinny diameter 7.7 or so and must be clipped into the same piece of pro

Half Ropes - Usually from about 8.1-8.5 in diameter and can be used as a twin or a double rope setup

Single ropes - As skinny as 8.9 and can only be used in a double rope setup - Never clipping into the same piece.

I think that covers it for the categories - let me know if I am wrong.

jmac wrote:When belaying doubles how do handle feeding the ropes at different rates? I assume for both twin and double you thread the ATC like you are rappelling?

This is really something you should learn in person, not on the interputers.

However, I will tell you how I belay:
First, I use an ATC-Guide, because of its jaws. Usually with gloves.
I keep both ropes locked. By making a slight unlocking adjustment, I can feed slack on a single rope easily. Taking rope on one line is a little trickier. I know three ways to do this, none are easy. One way is to pull on both ropes, and let the one you are not taking simply slide through your hands. Another is to briefly feed slack on the other rope, then take both simultaneously. A third method is to grab the brake side of the other rope with your feed hand; pull the take rope with your brake hand, then back to a braking position; then grab both ropes with your feed hand to slide your brake hand back up.

Get two friends, go to the climbing gym with some double ropes, get on a TR that has quickdraws hanging. Have one person actually belay you on TR, and have a second belayer mock-belay you using the doubles on mock-lead.

Better yet, hire an instructor.

Jmac, I'm more convinced than ever that twins are probably a good option for you. They are way easier to deal with than half ropes, both ropes feed at the same rate. Just beware that the super skinny ropes are hard to brake with. Use an aggressive device, and wear gloves.

jmac - if you want two ropes that can do the work of one - go with Half ropes - I use the beal ice line 8.1mm. Together they are as a light as a 10mm single, can be used in twin or double setup and have a wicked soft catch...They aren't super durable and you will likely retire them after your trip, but they are friggin' sweet.

Please be clear that using double ropes not rated for twin use will result in significantly higher forces on you and your gear. This is dangerous. Twin ropes are designed with more stretch than single/double ropes. I have no input as to which would be better for you, but I don't want to read about blown back, blown gear, or blown anchor/splat.

JMAC:

Go with the half rope system...it is more versatile.

definitely go with the halfs instead of the twins. much more versatile, particularly for the type of climbing you will encounter there. i honestly don't understand why anyone buys twins. they don't save that much weight over halfs.

There are half ropes which are rated for use as twin ropes, and there are those which are not.

Some examples are PMI Verglas 8.1's, newer Edelweiss Dynamic 8.3's, and Metolius Monster 7.8's are rated for both twin and half technique.

If the rope is rated for use as a half, it may not necessarily be rated for use with twin technique. Look at the ratings.

Perhaps another option would be to use a single, say 9-9.8 single and a tagline of 3-4mm for pulling lead line after rappel. Also comprises lower overall bulk for backpacking. Just my dos centavos.

Juan

jmac wrote:I will be traveling and climbing all over Europe next year with my gf. I was planning on only bringing one rope, but after doing some research I see that many routes require 2 ropes to descend.

Been to Europe climbing a few times in the last year or so. Kinda had the same dilema as you. When you're a party of three, it makes the options a bit more reasonable (you'd need a pair of ropes regardless).

My bet is you'll spend a fair bit of your trip doing single pitch and probably sport routes. That makes a single rope a good option.

I've used doubles and twins but usually with a party of three. If it were me, and, knowing the kind of stuff I climb (multi pitch one day, short single pitch the next, repeat until trip is over) and space was a consideration, I'd pack a light single only. I might bring a 6mm tag line to carry in a bag on the harness for those routes (very few is my guess) where you'd need two ropes to get off. That way I could still effect a long rappel should the need arise.

I'll imagine that you're way more experienced using a single rope? Not that you couldn't learn to use doubles or a set of twins, but, for single pitch half rope length routes, they're kinda unneeded. Be way less hassle to just have one rope.

Kind of depends what and where you are climbing too. "All over Europe" is a big venue. Alps and alpine climbing primarily? If weight and space is that much of a consideration then you probably aren't going to be lugging ice gear, boots, crampons, etc around. That would limit you to rock routes. And, depending where, there's a gob of multi pitch that are fixed for descending with a single rope. So, you'd "need" two ropes on the rare occasion not as a general rule. Unless that was the type of venue you were shooting for.

So, really, it kinda depends on what type of routes you'd be doing.

If you like long alpine rock and tend towards half the time something really easy, then I'd probably go with twins or doubles as you could use them single for the scrambly routes at the easy grades, where you'd maybe need a rope for a short belay on easy fifth (and could double a double or single twin...geez, that's almost confusing!) and/or a short rappel.

But, if you'll be camped at Ceuse for a month working your proj, then, I'd say go single.

So...tell us what kind of stuff your going to be climbing and where. Some examples of routes you've researched that required a couple of ropes.

Cheers!