Cowstail Lengths

Cantclimbtom

Well-known member
Noting the short and log cowstail pic above. Question about the krabs on the end of cows tails.
I don't know if I've heard of many cavers who uses non locking krabs that are wiregate - always solid gates. Why? as wiregate are lighter and probably better resistant to mud in the gate?

If that is too much of a digression from the lengths, which is the original post, please ignore me.
 

dougle89

Member
Thank you all for the input, some useful points put out. I appreciate that this kind of thing is very user specific. Just tied these off at this length, short Crab top sits at mouth level, long just Above head when standing so will comfortably reach ascender when climbing. Got a fair bit of excess on the barrel knots but don't want to trim just yet till I've tried setup a few times and find what's best
 

Attachments

  • 20231109_173320.jpg
    20231109_173320.jpg
    117.7 KB · Views: 43

Huge

Well-known member
Noting the short and log cowstail pic above. Question about the krabs on the end of cows tails.
I don't know if I've heard of many cavers who uses non locking krabs that are wiregate - always solid gates. Why? as wiregate are lighter and probably better resistant to mud in the gate?

If that is too much of a digression from the lengths, which is the original post, please ignore me.
They are my cowstails but I'm not sure I can give you a definitive answer! Wiregate crabs look like they would be less robust. Don't know if that is the case but I can accept that they won't be affected by mud so much. Not that mud seems to be a great problem. Maybe I'm caving in the wrong (right!) places? I don't think the weight saving is an issue at all. The handful of grams saved by having one or two wiregates on your cowstails makes no real difference.
 

pwhole

Well-known member
Thank you all for the input, some useful points put out. I appreciate that this kind of thing is very user specific. Just tied these off at this length, short Crab top sits at mouth level, long just Above head when standing so will comfortably reach ascender when climbing. Got a fair bit of excess on the barrel knots but don't want to trim just yet till I've tried setup a few times and find what's best

In the photo above, why not just put an extra turn on the barrel knots? Or even two, with that much spare? It seems a shame to waste good dynamic rope when it can help you in a crisis, and the more turns in the barrel, the more shock absorbency, as you're essentially making a rope spring. Those tails will really get in the way.

I use the 'rope access' setup, with a very short central loop, about 15cm extended and with a snapgate krab on, then two mirrored overhand knots on the central krab to the short and long cowstails with screwgate krabs (the same Petzl ones for twelve years and they're still fine). My short is usually twice the length of the central loop, and the long is twice the length of the short - and I can easily reach the top of the krab on the long one (left side) with either arm. As Mark pointed out, a long knot tail really isn't a problem if they're well-tied, and I never have more than about 8cm.
 

dougle89

Member
In the photo above, why not just put an extra turn on the barrel knots? Or even two, with that much spare? It seems a shame to waste good dynamic rope when it can help you in a crisis, and the more turns in the barrel, the more shock absorbency, as you're essentially making a rope spring. Those tails will really get in the way.

I use the 'rope access' setup, with a very short central loop, about 15cm extended and with a snapgate krab on, then two mirrored overhand knots on the central krab to the short and long cowstails with screwgate krabs (the same Petzl ones for twelve years and they're still fine). My short is usually twice the length of the central loop, and the long is twice the length of the short - and I can easily reach the top of the krab on the long one (left side) with either arm. As Mark pointed out, a long knot tail really isn't a problem if they're well-tied, and I never have more than about 8cm.
Good shout about extra turns on the knots, will have a go at that
 

hannahb

Active member
Wiregates: they're probably better. I think it's just habit that cavers don't choose them. Perhaps they are/were more expensive and less widely available at one time?
 

wellyjen

Well-known member
Wiregates: they're probably better. I think it's just habit that cavers don't choose them. Perhaps they are/were more expensive and less widely available at one time?
Some still have a pronounced hook where the gate latches, which can hang up and make taking cowstails off trickier. There are wire gate designs now that look like they are much less snaggy than they used to be. Maybe not as good as the Petzl key nose design that makes them such a fine cowstail krab. I don't currently own any wiregate krabs, so can't say.
 

JasonC

Well-known member
... I wonder if there's a maximum length we should go to though, particularly for taller people. If you do fall, the longer the cowstail is means you'll fall for a longer time, before being stopped by the cowstail. This means that you will be accelerating for longer and will therefore achieve a greater speed and higher loads when you do come to a stop. At what point does this become dangerous?
Presumably a higher stopping velocity would be offset by extra stretch in the rope, so a few cm more or less is likely to make a negligible difference to the impact on the caver.
 

ChrisB

Active member
a higher stopping velocity would be offset by extra stretch in the rope
Indeed, which is why we use the concept of 'fall factor', which only depends on the distance fallen compared to the amount of rope available to absorb the shock. If there's an issue here, it's not how tall the caver is, more about the difference in length between long and short cowstails, and where they're clipped to - if the anchor of your short one fails, you fall onto the long, so there's an argument for not having any more slack than you need to test your descender. It may be academic, as I can't see how you'd fall the full length of your long cowstail in situations where you're hanging on the short one, so it will be less than FF=1. The potential for bigger FF is when you're standing on a ledge or a traverse and your harness is above the anchors.
 

Loki

Active member
I was taught to hold the cowstail out horizontal from waist , holding the Kara. Shouldn’t be any slack. Works for me. For the long that is.
Short, we’ll if your rigger is rigging the rebelay after clipping the bolt and hanging off it, ties the knot and clips to rebelay anchors befor removing their descender, you shouldn’t have any issues passing it later. I had a habit of rigging the rebelay before committing my weight to it, then everyone struggled to pass it later.
 

Huge

Well-known member
Presumably a higher stopping velocity would be offset by extra stretch in the rope, so a few cm more or less is likely to make a negligible difference to the impact on the caver.
Except it's been stated a number of times in discussions on this forum that due to the very short length of dynamic rope in the cowstail, the amount of shock absorption offered by the actual rope is negligible. It's the tightening of the knots that provides most of the shock absorption, which is why I've got an extra turn on the barrel knots of my cowstails.

I'm conversant with fall factors but from what's been discussed on here recently, it seems that they don't really work with cowstails, due to the very short length of rope involved. It's more important to limit the distance fallen and use knots providing a good amount of shock absorption.
 

cap n chris

Well-known member
This thread is a repeat of a large number of others. The search feature in the Equipment section of UKC is not being used frequently enough.
 

Bob Mehew

Well-known member
Indeed, which is why we use the concept of 'fall factor', which only depends on the distance fallen compared to the amount of rope available to absorb the shock. If there's an issue here, it's not how tall the caver is, more about the difference in length between long and short cowstails, and where they're clipped to - if the anchor of your short one fails, you fall onto the long, so there's an argument for not having any more slack than you need to test your descender. It may be academic, as I can't see how you'd fall the full length of your long cowstail in situations where you're hanging on the short one, so it will be less than FF=1. The potential for bigger FF is when you're standing on a ledge or a traverse and your harness is above the anchors.
It is worth remembering that the fall factor concept only really works for longer lengths of rope. When using cows tails, the connectors, be they crabs or D rings, are a reasonable fraction of the length of the cows tail. So the actual fall can be much longer than the 'simple' length of the cows tail rope and worse still, instead of shock absorbing rope, part of the gear arresting your fall is steel. Fall factors in such case can amount to more than a factor of two, the usual limit for climbers falling on their rope. The shock arising even from short falls can be quite high and potentially injurious, because there is less rope to absorb the energy from the fall. There was an excellent paper by the FFS (french speleological federation) some years ago and a translation was put up on the old BCA web site, see https://web.archive.org/web/2020081...h.php?media=rope_testing:lanyard_tests_v6.pdf which goes into this.

Except it's been stated a number of times in discussions on this forum that due to the very short length of dynamic rope in the cowstail, the amount of shock absorption offered by the actual rope is negligible. It's the tightening of the knots that provides most of the shock absorption, which is why I've got an extra turn on the barrel knots of my cowstails.

I'm conversant with fall factors but from what's been discussed on here recently, it seems that they don't really work with cowstails, due to the very short length of rope involved. It's more important to limit the distance fallen and use knots providing a good amount of shock absorption.
As for whether an extra turn in a barrel knot is significant in energy absorption - it is a good question which we have yet to answer. We are still working on the topic. What is clear is that the barrel knot absorbs energy in a different manner from other knots. You will have to wait a while to see.

PS - any one got access to a 2 tonne joist for lifting? We would like to do some drop tests but no longer have a rig.
 

pwhole

Well-known member
I once climbed far too high whilst on a traverse and as I was moving my short over to the next belay loop the tiny ledge I was stood on snapped off and I fell onto my long - not the whole length, but most of it - certainly more than FF1. I got a bad jolt, but if I'm honest, it didn't really hurt that much. But I did have about three and a half turns on the barrel knot, and I certainly couldn't undo it again afterwards, even with soap applied. Having once fallen about 3m (onto my feet) whilst free-climbing, I'll take the long cowstail every time ;)
 

Mark Wright

Active member
As for the long cowstail, most people tie it nice and long to give plenty of flexibility to move when it's clipped in but not so long that if you fall, you can't reach whatever you're clipped into, to pull yourself back up. I wonder if there's a maximum length we should go to though, particularly for taller people. If you do fall, the longer the cowstail is means you'll fall for a longer time, before being stopped by the cowstail. This means that you will be accelerating for longer and will therefore achieve a greater speed and higher loads when you do come to a stop. At what point does this become dangerous?
I remember doing an after work bridge jump with Simon Nadin off the Menai Bridge on a couple of 50m low stretch ropes in the mid 80's. We both had very big rope loops dangling below us into the darkness. It was the biggest loop I had ever jumped with, and I did a lot of bridge jumping in those days. I can tell you some interesting stories!!

When we first climbed over the railings we were surprised to see about 10 people on the gantry all planning on jumping at the same time, but from opposite sides, about 5m apart!! I still can't believe we got away with it!

We fell a long way before the ropes tightened and took us into a big, fast, pendulum swing and up the other side. You go a lot higher on low stretch ropes, and get a second dynamic jolt on the way back down. I don't ever remember the forces being particularly uncomfortable. We went back for more on another, much narrower and taller bridge we had a railway line closure for the following day. We were prepared for it though, with our hands already holding the ropes ready for when they went tight, which helped us keep more upright, and we did use climbing harnesses with a slightly higher attachment point to a caving harness. You would naturally try grasping for the cow's tail rope in an accidental fall, as would probably be the case in a cave situation..

After the Menai Bridge jump with Simon, Chris Rhodes and I talked him, over a few pints, into taking the following week off work to practice for the British Indoor Climbing Championships in Leeds. He originally hated the idea of climbing competitions but someone had put his name forward. He took our advice, won the British Championships and then went on to win the World Championships.

I suppose it becomes dangerous at the point when falling a further distance could result in you hitting something on the way down that could cause a much more serious injury than any impact force from a fall onto a cow's tail is ever likely to give you, like bashing your head against a wall and being suspended, unconscious, in an upside down banana position with a blocked windpipe!! ABC, oh and that suspension trauma / syncope / intolerance thingy. Just ABC for me please.

The forces of gravity in industry are the same as down a cave, and in industry the aim is to always reduce, so far as is reasonably practicable, the distance and consequences of a fall.

Got some rope cowstails from Inglesport and was just retying them onto my crabs then got to thinking is there a best practice for the length of the two legs? Appreciate it's not a one size fits all job

How did you get on with your previous cows'tail lengths?

I made my first cow's tails as long as an experienced member of my club suggested. I made a few adjustments over a few trips, particularly one down Juniper Gulf, and I just make any new ones the exact same lengths as the last set. I don't even know what the leg measurements are.
 

mikem

Well-known member
This thread is a repeat of a large number of others. The search feature in the Equipment section of UKC is not being used frequently enough.
Unfortunately it isn't fit for purpose! & that is the way with modern social media, there is so much info out there that it's quicker to ask than trawl through...

From previous posts on here, I believe that the BCA test rig is being re-established.
and I just make any new ones the exact same lengths as the last set. I don't even know what the leg measurements are.
Surely that means they are getting slightly longer over time, as the used ones will be tighter?
 

dougle89

Member
How did you get on with your previous cows'tail lengths?

I made my first cow's tails as long as an experienced member of my club suggested. I made a few adjustments over a few trips, particularly one down Juniper Gulf, and I just make any new ones the exact same lengths as the last set. I don't even know what the leg measurements are.
This is my first time hence asking experienced members 😅 did a search and the number of not relevant results led me to ask again
 
Top