UKH

Just read this thread about extending the belay device on abseil with a Petzl connect adjust: https://www.ukhillwalking.com/forums/gear/abseil_extensionclove_hitch_question...

In that thread there is a link to an article discussing the use of Petzl adjust in this way, but that article also discusses the use of a 120cm sling, which is what I use for this situation (girth hitch the sling to the belay loop).

Interestingly that article suggests attaching the sling to your harness with a basket hitch instead of a girth hitch. I have heard that basket hitches weaken slings less than girth hitches, but I wouldn't have thought it would be enough to make a difference for abseil extension. (Or if it is then surely it means your sling is too knackered to be using).

What are everyone's thoughts on this? For those whom extend abseils with a sling, how do you attach it to your harness and do you think it's worth considering the use of a basket hitch?

In reply to mcawle:

I guess having it girth hitched means you are less likely to drop it if doing multiple abseils and clipping in and out?

Basket hitch should double the strength of the sling and girth hitch would weaken it by about 50%. Either way the strength will still be loads for an abseil. 

I usually girth hitch it but haven't looked into it too much, just the way I learned. 

In reply to mcawle:

https://dmmclimbing.com/Knowledge/December-2011/Improvisation-Lark-s-Foot-o...

In reply to mcawle:

A 120 in a basket hitch is 60cm long. To make it 60cm long using a girth hitch you need to double it up.

Doubling it up doubles the rated strength but then girth hitching reduces it to 50% so you end up with it at roughly its rated strength.

However you look at it, its completely academic anyway - if you are generating forces that approach the breaking strength of a sling there are bigger issues with your abseil set up!

If I am extending to abseil I normally use whatever's to hand - a 120 basketed, a 60 girthed or my other prussic girthed.

In reply to cp123:

If you double it up and it's larks footed (whilst doubled) each strand still has it's rated strength reduced by 50% - so you don't end up with roughly the same as it's rated strength, you end up with 50% of the rated strength, as the strands aren't redundant unless you tie an overhand in all 4 strands. Still, 50% of full sling strength is plenty for me! I would just leave it as 120cm and tie a couple of overhands in it to clip to. 

In reply to joshtee25:

Yes but you have 4 strands over 2 if the 120cm sling when girth hitched is the same length as a basket hitch.

In reply to mcawle:

Thanks all for the replies - yes I'm aware of the basket vs. girth hitch strength (and have seen that DMM video). I normally girth hitch with a couple of overhands, closest one for belay device and then the second one to give options for clipping into the anchor at less than full length. I think this is pretty standard and what I have always done. Agree that the strength reduction of a girth hitch still leaves more than enough security for abseiling so I guess that answers my question right there.

In reply to mcawle:

It depends what you want to do. A 120ck sling larks footed to your harness with an overhand knots 1/3rd of the way along makes a great improvised abseil extension for multi pitch retreats. Basket hitching the sling can be useful in some rescue scenarios. Clove hitching the belay krab onto the Petzl connect is another improvised technique that works quite well if you don't have the dual version.

In reply to nickcj:

Sounds like a good idea, but I can't visualise it. Are you adding the belay krab to the 'live' section (assuming the anchor krab is attached to an anchor)? 

In reply to mcawle:

Larks foot. 

In reply to mcawle:

Tying the sling on with a bowline on the bight around the harness tie in points is another option and arguably significantly better than either a girth hitch or a basket hitch.

In reply to Mark Stevenson:

Not heard of this before. Interested to know how it may be significantly better

In reply to Mark Eddy:

I've been doing this with an aramid sling for last couple of winters after Edelrids testing on slings. The aramid slings have cut through belay loops when larks footed to them in drop tests! The bowline on a bight creates a fixed loop which is easy to tie/untie and can't slip.

In reply to nufkin:

The belay krab goes between the larks foot and the connect adjuster. You need to add it before the lanyard is loaded.

In reply to mcawle:

If you are worried you could just clip the belay device to the belay loop on your harness 

In reply to mcawle:

When I'm teaching this to novices I usually use show a range of different options; larksfoot, basket hitch, basket hitch with an overhand knot (this is what I usually use myself), a 60cm sling with a screw gate, half rethreaded overhand (I think theres some pics of this on my instagram if you've not seen it before) and the Bowlin method Mark suggested. 

The important thing I think is to understand the limitations of each one. 

Using a sling and larks foot as a makeshift lanyard for a single, simple, short abseil descent is fine. If theres loose rock, rock edges, a long distance to go, I usually use a basket hitch with an overhand to give me some redundancy in my lanyard.

The Bowlin or other 'tied' methods are also good for not reducing strength in the sling, but in normal use this isn't too much of a concern for me.

If I know I'm going to be doing a lot of abseils (eg. in the alps, a bolted sport route descent etc) I almost always take a purpose made dynamic lanyard to put on my harness specifically just for the descent. 

In reply to Mark Stevenson:

Ooh this is rather clever! At first I thought it couldn't work because of needing to pass the bight over the loops, but of course with a sling you can just pass it over the other end.

I have no idea whether it is actually stronger than a cow hitch, certainly slightly slower. It does avoid the slippage issue that we normally have to worry about with knots in slings.

In reply to LucaC:

On the topic of various things being fine, as long as one is aware of the limitations, what about the leg loop back-up method? That's what I use (in my personal climbing) for simple, short abseils - very quick and convenient. I reserve extension with harness loop backup for multiple/longer/complicated abseils.

In reply to bpmclimb:

I must admit, I really dislike this method.

With the slightest lifting of the leg, or twisting one way, the prusik can easily touch the belay device, meaning it won’t lock.

Its better than nothing, but I’m not a fan.

In reply to jezb1:

Agreed - that is the potential hazard; however, I find those things never happen in practice, because I've always got my right hand on the knot, with my thumb over the top. 

In reply to bpmclimb:

But what about when you let go? Doesn’t have to be dramatic rockfalls or anything. 2 separate people I know let go after being stung by wasps / bees at Tremadog a couple of years ago!

In reply to jezb1:

I quite like abseiling on the Alpine up in click up mode. Locks up if you let go of the rope and saves the hassle of prusik back ups. Yes it is a bit of a cumbersome device and quite easy to drop when threading it but I often find myself taking it on routes requiring multiple abseils.

In reply to bpmclimb:

Totally agree with Jez here, leg loop backup is horrible. You can use strong points on your harness to set up a fully rated abseil setup, why make it suboptimal by using your leg loops which aren't rated or designed for the job. 

I always make the argument that at some point, someone will forget to put a belay plate on, or some other catastrophic mistake, and hopefully if they have their prussic on their belay loop then that might save them. Not sure a leg loop would. 

Theres just no need to use the leg loop with a stronger option being just as easy to construct. 

In reply to jezb1:

Can't ever remember letting go, and I've done thousands of them - literally. If I consider the very rare scenario where I let go, and make that also coincide with the twist or leg up enough to release the knot is multiplying degrees of unlikeliness - to make it very unlikely indeed. 

You get better at doing it, too. I use a short prussic tight to the leg loop, I don't put my right leg high, and I don't let go - ever. I don't think of it as a 100% safe thing - it's more like a safer variant of abseil with no backup at all (which I also do on occasion, in my personal climbing, for very short, quick abs). Which is arguably a healthy way to view all abseiling - somewhere along a spectrum of security, and not black-and-white. Let's remember that you really don't want to be letting go the belay loop prussic either - you're just that bit more likely to get away with it. 

I'm not pretending it's as safe as belay loop, to be clear, and I wouldn't recommend it to others in an unqualified way, or use it on long or complicated abseils, or in an instructing/guiding context - just the sheer convenience of it on simple, single abs in personal climbing, for me, outweighs the slight reduction in safety.

In reply to bpmclimb:

But if we’re going to say “I never let go”, why are you using a prusik?

I expect your answer will be for when you unexpectedly let go, for whatever reason?

In reply to bpmclimb:

Remember that past performance isn't an indicator of future performance! 'I've always done it this way' isn't really a good reason to continue doing something.

There is however one good reason to use the leg loop for your prussik and thats for the planned passing of a knot on abseil.

In reply to mcawle:

I think the most important point in all of this is that a sling is plenty strong enough however you attach it to your belay loop, as long as you are always tight directly below the anchor. Aramaid slings have been found to cut through belay loops in drop tests, so make sure that you are never in a position to drop onto one...

In reply to Will_Thomas_Harris:

Have you got a source for this Will? I would be interested in reading it.

In reply to jezb1:

Not altogether true!

That's the answer in part: in confers some extra protection in the very unlikely event I do let go. But that's not the whole point (perhaps not even the main point), because it also adds some friction, which is very convenient for controlling the speed of descent, and being able to pause for a while and let the prussic grip rather than your hand (but still keep you hand on it, of course) is a nice, comfortable option to have. I find all this much more user-friendly and much quicker to deploy, and I like having my main controlling hand in that position by my hip - just where it would be with no backup, just less effort.

In reply to LucaC:

Personally I put the prusik above the atc for this.

In reply to bpmclimb:

I think we probably fundamentally disagree on the main point of a prusik.

For me the main point is an emergency back up, any other points are bonus by products.

In reply to LucaC:

Hi Luca

I don't have a source, sorry, it was discussed on a training course and originally came from (as far as I can remember) some tests that had been carried out by Edelrid. 

In reply to Will_Thomas_Harris:

Beal's Dynaloop is a sewn loop of dynamic rope (7.3mm I think) so it will hold a factor 2 fall. You can also use it as a 'sling' while climbing. Good choice for extending an abseil device and clipping into a rappel anchor.

In reply to nufkin:

I guess. The idea (of single sling or) connect  is that furthest away from belayloop is the biner you use to attach to the anchor. Between said biner and your harness is the belay/rappel device (as I don’t have a connect I’ve just used a 120cm dyneema sling girth hitched to the belay loop and a simple overhand knot to act as a stopper to keep the rappel device at a good distance).

free tip, when you’re ready to start descending and unclip from the anchor, clip the biner to the strand you need to pull (assuming you’re using half ropes).

In reply to Big Bruva:

Actually although the original ones were 7.3, the latest model is 8.3mm and considerably more bulky and heavy.

In reply to mcawle:

For me, the advantage of using a basket style set up rather than girth hitch is that if you feed the sling through the tie in loops, offset the ends and then tie with an overhand you have 2 independent legs - one leg for the belay device, and the longer one to clip the anchor. Which I find makes rigging rappels and moving around at the anchor a little easier than with a setup of one leg with a knot tied partway along.

In reply to Everyday Normal Guy:

Don't you find untying a loaded overhand knot in a sling a real pain ? 

In reply to GrahamD:

No, it's typically fine and doesn't take much effort to undo. Multiple free hanging raps will tighten it up more but it still usually doesn't cause that much grief. I had one sling (Trango, blend of dyneema and nylon)  that was always a pain to get knots out of so i avoided using that one, but my regular dyneema BD slings are fine.

In reply to Everyday Normal Guy:

You can do this with a girth hitch as well. Make 2 loops of different lengths with your sling and then girth hitch them to your harness.

You have to ensure that you put a single twist in the sling as you create the 2 loops, otherwise the girth hitch can theoretically slip until it comes undone.

This set-up will be tidier and sit better on your harness. It will also give you slightly longer loops.

In reply to jezb1:

I may have overstated that. Emergency backup is very much part of it for me, too. I think that in that respect the leg loop provides a high degree of safety while not being foolproof: only slightly less (arguably) than the belay loop method, which isn't foolproof either - of course, it's not 100% guaranteed to grip when hands free wherever you put it. 

Where we do disagree, I think, is the degree of safety which can be conferred by the leg loop method. To quote your earlier post "with the slightest lifting of the leg, or twisting one way, the prussic can easily  touch the belay device, meaning it won't lock". This is so far from my experience with my own setup that I wonder if you've actually experimented in practice to get this outcome - or perhaps you have but not used a loop of appropriate length. 

I notice from your videos (a resource which I very much appreciate by the way - I've watched pretty much all of them with interest) that you favour fairly long prestitched prussic loops, which appear work well for the various applications you demonstrate. If you use one of those on the leg loop, I imagine it would be rather easier to get the loop to touch the belay device.

I've experimented several times in the past with trying deliberately to get the leg loop prussik to fail, and have found it very difficult to achieve in practice, assuming that the loop and knot are compact enough. Prompted by this thread, I tried again while descending from a route the day before yesterday, with a variety of body positions, and completely failed to get the prussic to unlock - it took a major contortion to get my leg high enough to make the knot and device touch, but even then I couldn't get the prussic to release. I also simulated being unconscious and dangling in various ways, and still the prussic held. 

I'm pretty much average height and build, and have had a similar result in previous tests with a variety of ropes and harnesses, all pretty much standard choices. FYI this week's scenario was abseiling on a pair of Beal Jokers, Renegade harness, 35cm prussic tied with four turns in 6mm cord.

These days I tend to carry two prussics on trad, one 35cm and one 45cm, on two mini-screwgates of different colours. That way I can quickly identify and deploy the one that's good for leg loop prussic, for descent from the short, single pitch trad routes with tree belays, which are so prevalent in my area.

In reply to LucaC:

Using the word horrible seems rather disproportionate. From the tone of your posts, anyone would think I'd suggested using a gear loop! A leg loop is a very strong point of the harness. I forget the exact proportion, but considerably more than half of the bodyweight is borne by the leg loops, which are designed to take the majority of the force of repeated, dynamic falls - are you really worried that the webbing is going to snap with a static load? Or, if you are, then why aren't you a lot more worried about the other "suboptimal" links in the chain: the knotted dyneema sling, and the variously rated "accessory cord" commonly used for prussic loops? 

To remind you, I wasn't suggesting using leg loop in an instructing/guiding context, just that it's a convenient option in a personal climbing context, for quick, uncomplicated retreat from short, single pitch routes. With a prussic of appropriate length, in confers a high degree of extra safety, and is much quicker to deploy than an extended belay device (especially if you want to take the opportunity to climb those routes without something larks footed to the belay loop, and generally getting in the way in the front of the harness). In the guiding context, we have to worry about using any equipment in any way not specifically recommended by the manufacturer. Personal climbing is an opportunity not to be quite so restrained, and to use a variety of methods which simply work.

Even in the instructing/guiding context, the leg loop method was taught for years by many MLTE course providers, not just to protect personal abseils, but also to back up e.g. tandem abseil rescues and the like. I was shown both leg loop and extended abseil methods on my SPA training years ago: the advantages and disadvantages of each was made clear - including the (rather obvious, I would have thought) caveat that you use a shorter prussic on the leg loop.

See reply to Jez above. There is a difference in the degree of safety conferred, but that difference can be made slight by using an appropriate length prussic loop. Admittedly, a leg loop and no belay plate would pretty much guarantee an awkward inversion with hard-to-predict outcomes, but I would suggest that forgetting to deploy the belay plate in climbing generally is about as serious as a mistake can get - like shouting "climb" to someone without putting them on belay. I notice we don't put in place a prussic to safeguard against that mistake! Some things just have to be done every time

There's no absolute need, but sometimes speed and convenience trumps a slight increase in safety. You say "stronger", but surely that's not the issue - we often use weaker methods, as long as they're plenty strong enough, knotted slings being a prime example. And it's not just as easy. Unlike many climbers (and instructors), who are typically only practised in one method (despite being very ready to trot out the usual arguments verbally), I'm well used to both methods in actual practice (though I say so myself), and I feel in a good position to judge: leg loop is considerably quicker and simpler. 

In reply to bpmclimb:

Glad you’ve liked the videos!

I used to use regular prusiks until about a year ago, I just don’t see any real advantage to not doing an extended style ab.

Even with a really short prusik it’s so easy to get them to touch.

I think it was 2006 when there was an accident in the US where a prusik touched the device, and didn’t lock, which seemed to lead to the extended version becoming the norm.

As a curve ball I quite like the extended ab but with prusik on the leg loop, but it’s not my go to..!

In reply to jezb1:

Fair enough! Dammned if I can get them to release accidentally, but maybe that's something about the way I'm doing it. It's definitely an area I continue to keep under review - especially now, as I'm currently in the RCDI consolidation phase, and giving much thought to what to say to clients and when to say it. Extended would always be the starting point, but would discuss leg loop if it happened to come up - or possibly slip one in myself if the opportunity arises, to engender a discussion ....

Just watched the escaping the system series. Are you planning to do one on traverse rescues? I imagine that would be a challenge on sling mountain

That didn't ping my radar. I was going to ask about real-life cases of failure ...

I'll try that next time out!

In reply to bpmclimb:

FWIW I've seen leg loop prusiks release twice. Both times on single pitch crags. Once when lifting the leg to use it to push the abseiler towards rope caught in a bush (on an MCI Trg I was working on). Once when someone was abseiling to retrieve a stuck wire and when they similarly lifted a leg to hold themselves in balance.

If I only show one its usually extended away (no disadvantages, works in a multipitch situation as well as single abseil) but if someone uses a leg loop prusik on say an RCI Assessment / asks about it I have no fundamental issue with it, I just ask about / explain the potential for failure.

When I'm teaching I tend to suggest that the prusik is a back up to the hand. If the hand comes off I'm in favour of a knot or wraps around leg/waist and leg to back up the prusik.