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Hi guys,
I have been using a sling for a while now larks footed to my harness knotted at about 30cm. I use this for three reasons, 1 for extending the belay device away from my harness, 2 to use the extra as a cows tail and 3 for abseil rescue "Y" hang rig. Now here is the crux, I talk about this with a number of people and some use the same method and some say that it is dangerous to larks foot and knot the sling as it makes the sling considerably weaker. I understand that knotting the sling and using slings like this in high fall factor situations is very dangerous but under loaded conditions with minimum falling force I can't see this a problem. What are the opinions if other people and what do you use?
Thanks,
I have been using a sling for a while now larks footed to my harness knotted at about 30cm. I use this for three reasons, 1 for extending the belay device away from my harness, 2 to use the extra as a cows tail and 3 for abseil rescue "Y" hang rig. Now here is the crux, I talk about this with a number of people and some use the same method and some say that it is dangerous to larks foot and knot the sling as it makes the sling considerably weaker. I understand that knotting the sling and using slings like this in high fall factor situations is very dangerous but under loaded conditions with minimum falling force I can't see this a problem. What are the opinions if other people and what do you use?
Thanks,
In reply to BB95:
Screw gate krabs, one at each end.
it also means you have two "spare" krabs around, for longer pitches, complex belay set ups etc.
Screw gate krabs, one at each end.
it also means you have two "spare" krabs around, for longer pitches, complex belay set ups etc.
Post edited at 10:22
In reply to BB95:
For what you describe a larks foot is fine. It shouldn't be shock loaded in this situation so the reduced strength is not an issue.
Attaching with a 'biner is no good in my experience as it flops around and the sling gets hung up on the gate at awkward moments.
What you describe is my standard set up for multiple abseil descents.
For what you describe a larks foot is fine. It shouldn't be shock loaded in this situation so the reduced strength is not an issue.
Attaching with a 'biner is no good in my experience as it flops around and the sling gets hung up on the gate at awkward moments.
What you describe is my standard set up for multiple abseil descents.
In reply to BB95:
Larksfooting and knotting does weaken slings significantly which is why when I put one round a tree root as a runner I only larksfoot it if it is likely to come off but as a cows tail/abseil loop the loads are only body weight so it is less important. Similarly though I just loop the sling through the harness loops like the rope. I can see no advantage in larksfooting it and a 60cm sling used this way is just the right length for me and in affect you have double the strength although I suspect that, in reality, that's not strictly true. When you larksfoot you need to be aware that there is a right way and a wrong way. One is stronger than the other and less likely to rub against itself.
Larksfooting and knotting does weaken slings significantly which is why when I put one round a tree root as a runner I only larksfoot it if it is likely to come off but as a cows tail/abseil loop the loads are only body weight so it is less important. Similarly though I just loop the sling through the harness loops like the rope. I can see no advantage in larksfooting it and a 60cm sling used this way is just the right length for me and in affect you have double the strength although I suspect that, in reality, that's not strictly true. When you larksfoot you need to be aware that there is a right way and a wrong way. One is stronger than the other and less likely to rub against itself.
In reply to BB95:
For multiple abs I larksfoot a 120cm sling through the tie in point, put a knot about 30cm up it and clip the device below it. I clip a screw gate into the end of the sling. This extends the abseil device to the right length and lets me clip straight in to an ab anchor with the screwgate in the end.
Like this: http://alpineexistence.com/wp-content/uploads/2014/03/photo-2.jpg
For multiple abs I larksfoot a 120cm sling through the tie in point, put a knot about 30cm up it and clip the device below it. I clip a screw gate into the end of the sling. This extends the abseil device to the right length and lets me clip straight in to an ab anchor with the screwgate in the end.
Like this: http://alpineexistence.com/wp-content/uploads/2014/03/photo-2.jpg
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In reply to DaveHK:
I agree, that's by far the most convenient method for multiple abseils. I've also used a Grivel cows tail but I struggle to rack it neatly and it's another bit of gear to carry so I'm not so keen. I do use it all the time for ice climbing however as it makes equalising the anchors very easy.
I agree, that's by far the most convenient method for multiple abseils. I've also used a Grivel cows tail but I struggle to rack it neatly and it's another bit of gear to carry so I'm not so keen. I do use it all the time for ice climbing however as it makes equalising the anchors very easy.
In reply to DaveHK:
That's what I do too; learned it last year from a guide on a DAV self-rescue course. I prefer
nylon slings for this application - generally more robust and abrasion resistant.
Extending the device also means the prusik can go on the belay loop, rather than on the leg loop where it can lever modern harness buckles open.
That's what I do too; learned it last year from a guide on a DAV self-rescue course. I prefer
nylon slings for this application - generally more robust and abrasion resistant.
Extending the device also means the prusik can go on the belay loop, rather than on the leg loop where it can lever modern harness buckles open.
In reply to BB95: Absolutely no issues in the 1st and 3rd scenario a you talk about. As regards the second scenario, if you only use it as a cow's tail in conjunction with abseils and are super careful to always be tight on from the anchors, again there are no issues.
However, using any sling as a general purpose cow's tail or lanyard is idiotic. If you fall even a short distance you will very likely either snap the sling at the knot or end up severely bruised or with internal injuries
Potential problems are more likely if people use dyneema for cow's tails for abseiling BUT then start to keep permanently or semipermanently attached to their harnesses. The first issue is that because it is always there it is far easier to get into bad habits and start clipping in where there are risks of shock loading as mentioned above. The second is that all the wear is continually concentrated at one point on the sling where it is larksfooted.
It is worth adding that an Edelrid aramid sling will probably perform much better than dyneema when used in this manner. First, with an aramid sling it is massively easier to undo the knot after it has been loaded. Second, it is pretty much impossible to melt aramid, where as moving ropes can easily damage dyneema. Third (and this is opinion rather than fact) the aramid will probably last longer.
Finally if you are doing loads of abseiling and do want to have a cow's tail permanently attached then the Beal Dynaconnexion is specially designed (iirc by a Canadian Mountain Guide) for this purpose and is a really neat and super safe option.
However, using any sling as a general purpose cow's tail or lanyard is idiotic. If you fall even a short distance you will very likely either snap the sling at the knot or end up severely bruised or with internal injuries
Potential problems are more likely if people use dyneema for cow's tails for abseiling BUT then start to keep permanently or semipermanently attached to their harnesses. The first issue is that because it is always there it is far easier to get into bad habits and start clipping in where there are risks of shock loading as mentioned above. The second is that all the wear is continually concentrated at one point on the sling where it is larksfooted.
It is worth adding that an Edelrid aramid sling will probably perform much better than dyneema when used in this manner. First, with an aramid sling it is massively easier to undo the knot after it has been loaded. Second, it is pretty much impossible to melt aramid, where as moving ropes can easily damage dyneema. Third (and this is opinion rather than fact) the aramid will probably last longer.
Finally if you are doing loads of abseiling and do want to have a cow's tail permanently attached then the Beal Dynaconnexion is specially designed (iirc by a Canadian Mountain Guide) for this purpose and is a really neat and super safe option.
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In reply to The Ex-Engineer:
Not to mention the harness itself, see Tragic Fate of Todd Skinner
That looks well useful, I'm getting one. Thanks
> Potential problems are more likely if people use dyneema for cow's tails for abseiling BUT then start to keep permanently or semipermanently attached to their harnesses. ... The second is that all the wear is continually concentrated at one point on the sling where it is larksfooted.
Not to mention the harness itself, see Tragic Fate of Todd Skinner
> Beal Dynaconnexion
That looks well useful, I'm getting one. Thanks
Post edited at 12:48
In reply to AlanLittle:
One has been on my shopping list for a while now but it is currently still a few items down from the top.
> That looks well useful, I'm getting one.
One has been on my shopping list for a while now but it is currently still a few items down from the top.
In reply to BB95:
Images of most options can be found at http:/www.multipitchclimbing.com
including some uncommon ones, see chapter 4, search for "Daisies and Other Tails" or just scroll down.
> What are the opinions if other people and what do you use?
Images of most options can be found at http:/www.multipitchclimbing.com
including some uncommon ones, see chapter 4, search for "Daisies and Other Tails" or just scroll down.
In reply to BB95:
I have the shorter Beal Dynaclip on my harness for situations where I may slip, and the cowstail gets loaded, and a Grivel thingy for other times.
I have the shorter Beal Dynaclip on my harness for situations where I may slip, and the cowstail gets loaded, and a Grivel thingy for other times.
In reply to BB95:
Larksfooting in and of itself isn't dangerous. Anyone who says it is hasn't done the maths. Maximum reduction in strength: 50%, breaking strain of average dyneema sling: 2.5kn. Divide this by that, you still have a sling that'll hold over a ton!
Larksfooting in and of itself isn't dangerous. Anyone who says it is hasn't done the maths. Maximum reduction in strength: 50%, breaking strain of average dyneema sling: 2.5kn. Divide this by that, you still have a sling that'll hold over a ton!
In reply to radson:
yes - get a very long one.
on bolts you can do a lot more with it than using it as a cow's tail:
http://people.bath.ac.uk/dac33/high/6TheBelay_files/image119.png
http://people.bath.ac.uk/dac33/high/6TheBelay_files/image123.png
http://people.bath.ac.uk/dac33/high/6TheBelay_files/image124.png
yes - get a very long one.
on bolts you can do a lot more with it than using it as a cow's tail:
http://people.bath.ac.uk/dac33/high/6TheBelay_files/image119.png
http://people.bath.ac.uk/dac33/high/6TheBelay_files/image123.png
http://people.bath.ac.uk/dac33/high/6TheBelay_files/image124.png
In reply to grump gnome:
Yeah I was curious as where I climb they are very popular. (Blue Mountains, NSW)
Yeah I was curious as where I climb they are very popular. (Blue Mountains, NSW)
In reply to The Ex-Engineer:
Is that not just a short section of rope? Could I not make one for a third of the price? Perhaps there's something I'm missing.
I just use nylon slings - a bit more dynamic, higher melting point, less slick, and multipurpose. On my harness dyneema is only for dogbones, after reading the reports it just seems like the more reliable option, unless you carry half of Joe Brown's up the wall with you.
> Finally if you are doing loads of abseiling and do want to have a cow's tail permanently attached then the Beal Dynaconnexion is specially designed (iirc by a Canadian Mountain Guide) for this purpose and is a really neat and super safe option.
Is that not just a short section of rope? Could I not make one for a third of the price? Perhaps there's something I'm missing.
I just use nylon slings - a bit more dynamic, higher melting point, less slick, and multipurpose. On my harness dyneema is only for dogbones, after reading the reports it just seems like the more reliable option, unless you carry half of Joe Brown's up the wall with you.
In reply to purplemonkeyelephant:
Yeah, that's what I did. Bought 3m of 8mm dynamic rope. Fig of 8 on each end and an alpine butterfly about a third of the way along for abseil device. Larks footed one end onto harness and a screw gate on the other end to clip onto anchor when doing multiple abseils.
> Is that not just a short section of rope? Could I not make one for a third of the price? Perhaps there's something I'm missing.
Yeah, that's what I did. Bought 3m of 8mm dynamic rope. Fig of 8 on each end and an alpine butterfly about a third of the way along for abseil device. Larks footed one end onto harness and a screw gate on the other end to clip onto anchor when doing multiple abseils.
In reply to purplemonkeyelephant:
The design is actually quite elegant and whilst you can make something perfectly workable out of a length of rope it will always end up bulkier and either heavier or less strong/durable.
The Beal design has double strands of 8mm where as Nemo's improvised one is around the same weight but only has a single strand which might be marginal in a (albeit unlikely) factor 2 fall scenario. Doing the same thing with 3m of thicker single rope will give the same security but with even bulkier knots and more weight.
It is a very similar situation as regards climbing slings - unless you are still buying nylon tape by the metre and knotting your own slings then I'd say you are missing something obvious: stitching always beats knots when comes to weight and usability.
> Is that not just a short section of rope? Could I not make one for a third of the price? Perhaps there's something I'm missing.
The design is actually quite elegant and whilst you can make something perfectly workable out of a length of rope it will always end up bulkier and either heavier or less strong/durable.
The Beal design has double strands of 8mm where as Nemo's improvised one is around the same weight but only has a single strand which might be marginal in a (albeit unlikely) factor 2 fall scenario. Doing the same thing with 3m of thicker single rope will give the same security but with even bulkier knots and more weight.
It is a very similar situation as regards climbing slings - unless you are still buying nylon tape by the metre and knotting your own slings then I'd say you are missing something obvious: stitching always beats knots when comes to weight and usability.
In reply to Nemo9:
I use the 6mm loop of cord that I use to tie on my chalk bag. Larks foot it thru tie in points, clip the other end to belay loop with a locker. Tie an over hand loop at the right place to clip my abseil device.
I don't need my chalk bag to be handy when abseiling. Usually, the cord loop holds my chalk bag around my waist and is tied with a sheet bend so it's always available. I just clip the chalk bag to something else when I need to abseil.
I use the 6mm loop of cord that I use to tie on my chalk bag. Larks foot it thru tie in points, clip the other end to belay loop with a locker. Tie an over hand loop at the right place to clip my abseil device.
I don't need my chalk bag to be handy when abseiling. Usually, the cord loop holds my chalk bag around my waist and is tied with a sheet bend so it's always available. I just clip the chalk bag to something else when I need to abseil.
Post edited at 00:47
In reply to The Ex-Engineer:
That's nonsense.
> However, using any sling as a general purpose cow's tail or lanyard is idiotic. If you fall even a short distance you will very likely either snap the sling at the knot or end up severely bruised or with internal injuries
That's nonsense.
In reply to The Ex-Engineer:
The problem with sweeping statements is that they are generally bollocks.
LD
> However, using any sling as a general purpose cow's tail or lanyard is idiotic. If you fall even a short distance you will very likely either snap the sling at the knot or end up severely bruised or with internal injuries
The problem with sweeping statements is that they are generally bollocks.
LD
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http://www.hse.gov.uk/research/crr_pdf/2001/crr01364.pdf An old study that has been posted before but see pg 76.
In reply to AlH:
ITYM Section 7.6?
> http://www.hse.gov.uk/research/crr_pdf/2001/crr01364.pdf An old study that has been posted before but see pg 76.
ITYM Section 7.6?
In reply to Lawrence:
More in depth video from DMM., saying much the same thing re slings and knotted slings. Bad idea!
vimeo.com/27293337
More in depth video from DMM., saying much the same thing re slings and knotted slings. Bad idea!
vimeo.com/27293337
In reply to AlanLittle:
For sports I have been using a Dynaconexxion for a couple of years now, to much mockery. WTF is that people say, then go on to tell me how safe a sling is if you don`t fall on it. I have stopped arguing now, just "whatever".
For sports I have been using a Dynaconexxion for a couple of years now, to much mockery. WTF is that people say, then go on to tell me how safe a sling is if you don`t fall on it. I have stopped arguing now, just "whatever".
In reply to SCrossley:
Ha, brilliant! Soloing's pretty safe if you don't fall too, right?
> ...then go on to tell me how safe a sling is if you don`t fall on it.
Ha, brilliant! Soloing's pretty safe if you don't fall too, right?
In reply to The Ex-Engineer:
The problem here isn't the sling. The problem here is falling onto cows tail - of any material. If you want to even contemplate falling like this you need a via ferrata brake.
> However, using any sling as a general purpose cow's tail or lanyard is idiotic. If you fall even a short distance you will very likely either snap the sling at the knot or end up severely bruised or with internal injuries
The problem here isn't the sling. The problem here is falling onto cows tail - of any material. If you want to even contemplate falling like this you need a via ferrata brake.
In reply to GrahamD:
Depends what you mean by "falling". A sling should be kept tight at all times, whereas if you had a bit of dynamic rope if there was an inch or two of slack in it you would most likely be OK.
If you're taking "leader falls" or falls with substantial slack you indeed need a VF kit.
Edit: Actually, thinking about it, if you take a "leader fall" onto a dynamic rope cow's tail, provided the anchor is fixed, that is a Factor 2 - time to start binning gear and rather unpleasant but not likely to kill you or cause things to fail. The difference with VF is that you can get factors higher than a 2 because you slide down the cable to the next anchor. OTOH, taking a Factor 2 onto a static system is going to cause serious injury or worse.
Neil
Depends what you mean by "falling". A sling should be kept tight at all times, whereas if you had a bit of dynamic rope if there was an inch or two of slack in it you would most likely be OK.
If you're taking "leader falls" or falls with substantial slack you indeed need a VF kit.
Edit: Actually, thinking about it, if you take a "leader fall" onto a dynamic rope cow's tail, provided the anchor is fixed, that is a Factor 2 - time to start binning gear and rather unpleasant but not likely to kill you or cause things to fail. The difference with VF is that you can get factors higher than a 2 because you slide down the cable to the next anchor. OTOH, taking a Factor 2 onto a static system is going to cause serious injury or worse.
Neil
Post edited at 10:28
This is a nice diagram comparing using a sling and something dynamic if you slip off a belay stance (fall factor 1 or 2 rather than a via ferrata fall).
http://www.bealplanet.com/2014/img/tableau-longes-us.jpg
http://www.bealplanet.com/2014/anglais/longe-dynaconnexion.html
http://www.bealplanet.com/2014/img/tableau-longes-us.jpg
http://www.bealplanet.com/2014/anglais/longe-dynaconnexion.html
In reply to elsewhere:
Hmm, possibly an expensive solution where a metre or two of bog-standard dynamic rope with a figure of 8/stopper in each end would do the job...
Neil
Hmm, possibly an expensive solution where a metre or two of bog-standard dynamic rope with a figure of 8/stopper in each end would do the job...
Neil
In reply to BB95:
'Dangerous' is overstating it in my opinion, pretty pointless would be my assessment.
I just abseil off my belay loop. If I need a temporary attachment to a belay I use whatever is handy, a bit of rope, a sling, a quickdraw or two. Never needed any kind of abseil rescue kit but if I did I'd improvise with what I had.
If you're comfortable doing what you do I'd suggest sticking with it.
jk
'Dangerous' is overstating it in my opinion, pretty pointless would be my assessment.
I just abseil off my belay loop. If I need a temporary attachment to a belay I use whatever is handy, a bit of rope, a sling, a quickdraw or two. Never needed any kind of abseil rescue kit but if I did I'd improvise with what I had.
If you're comfortable doing what you do I'd suggest sticking with it.
jk
In reply to GrahamD:
Perhaps something like this is the solution? :P
http://www.kakibusok.plus.com/Equipment/CTDQ2/CTDQ2.htm
Perhaps something like this is the solution? :P
http://www.kakibusok.plus.com/Equipment/CTDQ2/CTDQ2.htm
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