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Rapping on a single rope using cord to retrieve rope

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 Rikardo 08 Oct 2021

I'm heading out to Nepal in Nov to climb a long ridgeline that will require some rapping and rather than use two skinny beal ice lines, where one rope would remain in a sack until the descent, I'm considering using a 60m skinny 8.5mm single and using 6mm tat to retrieve the rope.

The route overall is 95% on snow n ice with a small rock band so hopefully minimising snagging obstacles.

I understand how to construct this setup but I'd appreciate some practical feedback?

thanks in advance

 girlymonkey 08 Oct 2021
In reply to Rikardo:

I didn't think rock bands were that into rapping generally? Fairly different genres, aren't they? 😜

 99ster 08 Oct 2021
In reply to Rikardo:

Andy Kirkpatrick's book 'Down' (page 326) is a good reference....

https://www.andy-kirkpatrick.com/shop/product/down

 henwardian 08 Oct 2021
In reply to Rikardo:

> I understand how to construct this setup but I'd appreciate some practical feedback?

I've looked into this a couple of times and done a trial or two but never used it in earnest. My observations were:

1) It is much more likely for the knot to get stuck (especially at the start of the pull) and a bit harder for it to get pulled down to you and more likely for it to get snagged just because you are pulling down a loop rather than a single strand.

2) If anything goes wrong or there are any unknowns, you have a bit less flexibility.

3) This might just be me but thin cord (I was using 4mm) has a couple of disadvantages: a) it is much harder to pull it hard and cuts into your hands and b) when you try and coil it, it gets knotted and into a much worse state than normal ropes.

People use it and get on fine with it of course but I'm not sure it would be a system I would take on the road, especially now that some companies are selling dedicated rap lines that are.... I forget... 7mm? Maybe that is something to look at that would weigh about the same?

Edit: Also a good critique of the system in action here: https://www.ukclimbing.com/forums/expedition+alpine/single_rope_with_thin_55mm_dyneema_for_abseils-421659

Scroll down to the big post by Mike Pescod.

Post edited at 09:59
In reply to Rikardo:

Having done quite a few easier winter routes with a similar set up (60m triple and 60x6mm pull cord), never had any problems, but the only time we ever ended up abbing, it was a bluebird day with no wind, and only a single rope length. The system worked perfectly, but conditions were very benign. For multiple planned abs, rather than an insurance policy, particularly somewhere more remote, maybe worth balancing the weight saving against the redundancy of having 2 useable ropes. The pull cord is obviously lighter than a rope but it's not negligible (about the size of a packed belay jacket in your bag). Maybe worth checking the weights to find out what the net saving actually is. Plus, if your ropes jam on the retrieval, because the pull cord comes down first, you don't have the worst case option of cutting the rope and carrying on with as much rope as you can, that you would with two ropes.

 Hovercraft 08 Oct 2021
In reply to girlymonkey:

Maybe he should Walk this Way?…

 Fellover 08 Oct 2021
In reply to Rikardo:

If using a skinny pull/tag line it can be really hard to pull. Consider carrying a microtrax or kong duck, use that to pull the tag line, makes it much much easier.

Obviously carrying one if you weren't planning to does add a bit of weight, but probably not as much as the saving between a tag line and a skinny double. It's also useful for other stuff like crevasse rescue, moving together and hauling a pack over a crux section (though whether any of that will be applicable on your route I don't know).

In reply to Fellover:

Don't know if it would be applicable but I carry some 8mm industrial type polypropylene if I know I'll only need the rope to ab. Mine weighs the same as Edelweiss 5.5mm aramid rope but has the advantage of potentially being useable with techniques that are applicable to normal climbing ropes eg belay plates. It can tend to kink a bit. Obviously comparable weight  but greater bulk than a single cord.

One should be able to join it to a dynamic lead rope for full length retrievable abseils (allowing for almost no stretch in the polypropylene rope) and if necessary it should be OK for bringing up a second.

Post edited at 15:08
In reply to Rikardo:

>I'm considering using a 60m skinny 8.5mm single

That's going to be fun to ab on....not! Aside from that, what's the risk of your rope(s) being damaged by rock/ice falling on them?  I think I'd rather have the redundancy of a second full-strength rope than lighter weight in the greater ranges.

In reply to Rikardo:

or use a Beal escaper?  I have no personal experience with it all

 RBK 08 Oct 2021
 Will_he_fall 08 Oct 2021

And more thoughts from Haley here about the Petzl Pur'line and possible uses: https://www.instagram.com/p/CS-bpVXs1Jx/

 HardenClimber 08 Oct 2021
In reply to oldie:

remind me what temperature polypro melts at?

In reply to HardenClimber:

> remind me what temperature polypro melts at? <

I think polypropylene rope melting point is usually given as 160-170 deg C.  (ie considerably less than nylon).

However IMHO used sensibly this is not a problem. Southern sandstone climbers of a certain age will have used, and been instructed with, polypropylene ropes (albeit thicker than 8mm). This was bottom roping with the rope running through a krab at the top and the hire ropes especially were certainly heavily used. I have used my 8mm (both doubled and single) for abseils with single krab and sit sling and belay plate and haven't noticed any damage. Obviously the polypropylene rope could be used simply as a pull cord but that would lose some of the simplicity of abseiling on a double strand (though the polypropylene could still be used as a weight bearing rope and cut up for abseil anchors in an emergency). Classic abseil no problem with melting!

You do make a very valid point and my post was only a suggestion for consideration. I think there was an accident with polypropylene rope breaking on abseil during the long  descent into Dungeon Ghyll....IIRC this was not due to melting.

Post edited at 17:50
In reply to Rikardo:

On snow/ice I’d say use a beal escaper. Get used to it and then I think it’s better than a tag line on an uninterrupted pull bc so much lighter. 
 

For rock band it might be good too and if it doesn’t look like a goer then just 30m raps? Might be better anyway for retrieval. 

 Misha 08 Oct 2021
In reply to Rikardo:

You can get 5mm or 6mm specialist pull cord, think it’s a bit tougher than normal tat. I’ve used the 5mm one (Beal I think) and it was fine, albeit on a pretty low stress route involving only about 5 abs. 

 Rikardo 08 Oct 2021
In reply to RBK:

Interesting article, thanks

 JStearn 10 Oct 2021
In reply to RBK:

I read Colin Haley's article about the Purline but wondered if anyone has further details on how it's rigged. Can you ab directly on the Purline + single or only on the single with some sort of biner block? This seems much more likely to get hung up, leaving you stuck with just the pull line. If the former, could you abseil directly off cord with the single over the cord? I can see how useful this would be if you had a lot of abseils and don't want to leave tons of gear.

 Fellover 11 Oct 2021
In reply to JStearn:

It's a while since I read the article and the facebook comment thread on Colin's facebook page (and I haven't re-read it), but my memory was that it's not necessarily recommended by Petzl to ab on it directly, but that Haley and co. do. The main issue being that as it's very thin you need to use a specific belay device, or two belay devices in line (or add friction in some way) so that you have enough control. The only problem I can imagine with abbing on it and a single would be relative slippage of the two ropes, with the Purline passing through the belay plate faster than the single. I have no idea whether this would actually happen or not, it's just something I'm going to test before I try and ab on the one I have. Unless anyone else pops up with the answer I'll post with how it goes when I get round to trying it out.

 JStearn 11 Oct 2021
In reply to Fellover:

I had a look at the manual and it does only show biner blocks, and cautions against using a knot block with a maillon. But in some of the pictures on the article, it definitely looks like they are descending on both strands with a belay plate. Could you tie both ends together and use two krabs with a regular ATC to avoid the issue of slippage? 

 rgold 11 Oct 2021
In reply to JStearn:

Here's a link to the article.  http://www.colinhaley.com/nugget-1-the-petzl-purline/ .  The pictures make it pretty clear that they are rapping with both strands through the rap device. Here's a link to the Pur Line manual. https://www.google.com/search?client=firefox-b-1-d&q=petzl+purline+manual .  It indicates the biner method used for single-strand raps and lists the knot jamming in a maillon with a caution.  It recommends joining the ropes with two overhands, not one.

The main advantages of single + tag line are for situations in which you want to be able to haul stuff with the tag line, want to be able to ascend the single line, and/or insist on belaying with a Grigri. 

For a mostly snow route with a rockband or two to rap over, it seems to me like a light set of twin ropes would be the optimal answer...

In reply to Rikardo:

Mentioning it purely out of thread completness, but another option is to use a fiddlestick to pull and retrieve the rope.

Apparently far more common in dusty/rocky canyoneering circles where draggin rope over that terrain is less optimal.

Worth looking into.

In reply to Rikardo:

I've used it with mixed success on routes where it's unlikely that I would need to retreat, or when I know the distance abed is not far and not draggy i.e. water ice. A severe downside to it is that for multiple pitch abseils it's a pain in the ass as you have to reset the rope each time because you are always pulling the same cord, not alternating like you can with a double rope. What I mean is that when you set up the rope for the next abseil, you can thread the pull cord through the anchor so that the next abseil is set immediately once the rope has been pulled down - at the next anchor you just pull the other rope. With a pull cord you have to set it up more or less fresh each time which is a bit tedious and only really worth it if you benefit from using a single rope system in terms of simplicity.

I am going to however throw another option into the ring which is most likely going to cause a ruckus. Twin ropes - really light, almost as simple to use as a single rope, the difference between that and a single/tagline will be minimal, it will definitely be lighter than doubles, you have a level of redundancy and you get full length abseils.

In reply to beardy mike:

Just because I was bored I worked out some stats:

Beal Gully twins, 60m weigh 4320g for a pair

Beal Joker 9.1 60m (might be a bit fat?) plus a 60m 5mm tagline weigh 4290g

Beal Icelines 60m weigh 4680g

BUT, the single plus a tagline, the tagline is sooo damned tangley that I wouldn't bother using a 60m version. This means an extra abseil for every 5 pitches of abseil i.e. more anchors etc and belay changeover... Having used a pair of twins extensively in the past, I actually really liked them even though many people on here told me I couldn't possible like them and that I was infact wrong...

Of course there is the converse benefit, that if you only need to do a 50m or less abseil, you could end up with a lighter system - imagine how light a 40m plus tagline would be if you only needed to do the odd 40m abseil...

Post edited at 16:47
In reply to beardy mike:

Is the kind of terrain that the OP is talking about more or less exactly what twin ropes were designed for?

 JStearn 12 Oct 2021

One use of the single not mentioned is if you are rope soloing, so twins wouldn't be an option. In this case, I think the tagline is the lightest way to get full abseils except for a Beal Escaper. That might also be an option for OP if the risk of snagging is low? 

In reply to John Stainforth:

I think they kind of originated from when half ropes were fat and they suited long bolted and alpine multi pitch routes. Yes they are specialist, but then so is climbing in the Himalaya... just taken a look at the Pur'Line mentioned above, got to be said that is a nice solution seems better than the tagline to me...

 d_b 15:40 Mon
In reply to Rikardo:

I noticed a couple of people suggesting the Escaper.  I did quite a number of experiments with one a couple of years ago before taking it on a route.  Results can be summarised as follows:

- You are unlikely to get dropped.

- Resting feet gently on a ledge does not constitute unweighting a rope for the purposes of the thing releasing.

- You are fairly likely to get it stuck if you aren't careful.

- Getting it to come down even in optimal conditions tends to take more tugs/bounces than the manual says.

- The thing really needs to be free hanging, which constrains your choice of anchors.  If it's lying across the ground it probably aint coming down.

It may be worth considering as it is light weight and all but I think Beal pitch it as a device for sport climbers for a reason.  You need a close to optimal anchor setup or you aren't getting your rope back.  Take a lot of tat to extend over edges and you might be ok though.

All the tests were in uk summer conditions.  I have no idea what happens if it gets icy.

Post edited at 15:52
In reply to Rikardo:

If you do go for a static tagline, consider getting a few extra meters more than your dynamic rope if you want to max out the length of your abseils - ie to account for stretch in the dynamic. 

 Rick Graham 18:02 Mon
In reply to Rikardo:

After bad experiences pulling the lighter line, have reverted to using a line strong and confidence inspiring enough to double  through the abseil krab/sling/tat.

This has the advantage of pulling on a full weight rope and therefore less chance of the nightmare scenario of being left with a tagline and no climbing rope.

Its easiest if you test out  the stretch of both rope /line types individually , hang both down a steep cliff and see how much stretch there is until your feet become unweighted. Some 6+7 mm accessory cord don't stretch much more than thin climbing ropes. Whatever the stretch difference, this can be minimised by putting both through one hole of a belay plate.

Tying together two equal ropes , the overhand is king for rolling over edges. 

For unequal ropes and because you are always pulling one rope, I find it most convenient to link the ropes with a screwgate.  This speeds up resetting the ropes at the next anchor and has always been surprisingly trouble free.

Despite all this experimenting over the years, now super skinny twins are available , I would recommend doing the sums on some 6.9 or 7.3s.

Post edited at 18:06

Whilst weight might be similar between a skinny single/tag line combo and a set of twins, I think there are definite benefits to using a single rope for some terrain. 

As others have said, where you want to haul a bag, or jug the lead line, a single/tag makes more sense. I find using a single on ridges much easier, as it's less faff when taking coils for moving together over different types of ground.

Post edited at 07:34
In reply to Will_he_fall:

Absolutely, each tool has its place. Just the other day I did a 200m rock route in the Dolomites using a single and a tag line because my partner was not very experienced and hadn't used double ropes before...

In reply to Misha:

> You can get 5mm or 6mm specialist pull cord, think it’s a bit tougher than normal tat. I’ve used the 5mm one (Beal I think) and it was fine, albeit on a pretty low stress route involving only about 5 abs. 

The thinner the cord the more prone to tangling. At 60m of 5mm -- did you find that a problem?

I've used 30m pull cord before (EDIT: with 60m rope for 45m abseil) and if you start using Tatt/para cord etc I find it OK in controlled practice situations but more difficult to manage when used in the wild. Scaling this up to 60m, I wouldn't want 60m of 4 or 5mm cord on a windy ridge. Sure it'll work well if everything is going right, but as soon as "it" hits the fan, the cord will decide to become a tangled ball.

Petz sell a somewhat expensive 6mm extra-static rope aimed at crevasse rescue and abseil (Tibloc and micro traction compatible) called "RAD Line" at 22g per metre https://www.petzl.com/INT/en/Sport/Ropes/RAD-LINE-6-mm . More useful than just pull cord. Maybe could be part of a solution? 

Post edited at 16:53
 Misha 21:09 Tue
In reply to CantClimbTom:

Only used it on one route involving 5/6 abseils and it was fine.

Yes, the Petzl 6mm cord looks handy.


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