Clipping 2 half ropes into a piece of protection?

I have climbed on routes in a team of 3 people where there is a traverse. I sometimes clip both half ropes into the protection to prevent a large pendulum fall for both of the followers. Does this increase the force on the gear I have placed? Could this be a problem if there isn't a lot of rope out in the belay and I have marginal gear only rated to 5-6kn?

Yes and yes. You could always have your first follower clip the second rope in.

If your marginal gear is rated for 6kN that is hardly marginal. A pendulum fall isn't going to put 6kN on it.

Though you should be aware on whether your ropes are recommended for twin use. Most half ropes are but you really should check.

Maybe better to say solid placement using gear with rating of 6kn. No reason to waste time debating that a crappy placement is still crappy no matter how many ropes go through it. If I were concerned, I'd just load distribute between a couple solid placements.

patto wrote:If your marginal gear is rated for 6kN that is hardly marginal. A pendulum fall isn't going to put 6kN on it.

Exactly. I've lobbed 25 footers on sport climbs (vertically, not swinging), and came up just short of 4kN. You're not going to reach 6kN on a swing regardless of how you clip the ropes. However, you could pull the piece from placement or rock failure, and clipping both ropes would increase the chance of that occuring. This is something you would have to evaluate in real time. If you're placing a piece that you know is solid, I wouldent have a problem clipping the ropes as twins.

One thing to take note is that you cannot freely go about clipping the ropes as halves, twins and halves again. When you separate the ropes and then bring them back together to clip them as twins, it is possible each rope has a different length and different amount of rope drag depending on how you clipped them. Then, if you clip them as twins and fall, the ropes could pull through the biner at two different speeds which is not good.

The skinny on the subject is that you can go from twins to halves mid-pitch, but it;s best to avoid going from halves to twins. If you absolutely must go to twins after already having clipped them as halves (such as in the scenario you describe), clip them using two different draws or slings, preferably of different lengths. I would clip one rope directly to the piece and the other with a quickdraw. That way if you fall and the ropes do pull through at different speeds, they are not in direct contact with each other since they have separate biners.

As said above, when using a double rope technique you either clip both ropes to all gear (as one would with twins) or each rope to every other piece of gear. You do not want to clip, one rope to the first piece of gear, second rope to the second piece of gear, and then both ropes to the third piece of gear.

The reason is because the ropes are going to be out different lengths and if clipped to the same piece of gear during a fall there will be differential sliding which will cause friction and possibly damage (melting) to both ropes. If you want to protect two people who will follow use a second piece of gear or second draw for the other rope.

I climb with half ropes and two seconds with some frequency. I never clip both ropes to the same carabiner, even though I'm not at all sure the business about them possibly running at different speeds is really a serious issue. Even if the differential running speeds turns out not to be a serious concern, there is another potential problem with halves-to-twins clipping: it can produce a substantial lifting force on the piece if the halves are running in widely spaced parallel lines that are then brought together at a single point. When loaded, this configuration will try to raise the single carabiner the double ropes pass through.

When inexperienced seconds are involved, having two ropes in a single biner is bad because the first person to arrive has to get their rope out of a carabiner with two ropes in it and all kinds of unanticipated things can happen. One is that both ropes are removed, another is that one rope is twisted around the other during removal.

But even with experienced climbers, unclipping one of two ropes, possibly while one of the ropes is running, is at the very least awkward. So I do one of two things:

(1) As 20 kN says, use two slings of different lengths and clip one rope to each sling.

(2) Only clip one rope and have the climber who arrives first remove their rope and clip the other rope in. This requires planning---you have to know who will arrive first and the way the ropes run has to place the second person's rope within reach of the first person at the piece where the changeover happens.

Really appreciate the info in this thread. I've been toying with the idea of leading on half ropes when in a group of 3 and this helped a ton! Thanks!

Thanks I have learned a ton from you guys thanks.