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The thread about which knot to use when absailing 2 rope lengths got me thinking.
It seems to be considered unreliable to tie two ropes together using a figure 8 and then absail along the rope because the knot might turn inside out and roll off the tails and fail.
Why is it then considered ok to clip into the belay with the rope loop tied with a figure 8 or belay from the rope loop tied with a figure 8? Is there not the same potential for the knot to invert and fail?
Thoughts?
It seems to be considered unreliable to tie two ropes together using a figure 8 and then absail along the rope because the knot might turn inside out and roll off the tails and fail.
Why is it then considered ok to clip into the belay with the rope loop tied with a figure 8 or belay from the rope loop tied with a figure 8? Is there not the same potential for the knot to invert and fail?
Thoughts?
In reply to ablackett:
Knot this one again, this knotty subject comes around every so often and is then strung out by people gettting tied up in little details.
I'd reef-er you to google before someone takes a bight out of you for trolling(line).
Knot this one again, this knotty subject comes around every so often and is then strung out by people gettting tied up in little details.
I'd reef-er you to google before someone takes a bight out of you for trolling(line).
In reply to ablackett: Not sure how the knot can invert and fail when it is restrained by the harness.
Al
Al
In reply to ablackett: I'm concerned that I don't know what a knot rolling or inverting means.
In reply to ablackett:
Abseil = German "down rope".
absail = "my dingy has lost it form of propulsion" - well maybe?
Chris
Abseil = German "down rope".
absail = "my dingy has lost it form of propulsion" - well maybe?
Chris
In reply to Chris Craggs:
Abbs ale="A type of stout usually drunk to produce a beer gut so as to disguise the fact they are actually a ripped monster"
Abbs ale="A type of stout usually drunk to produce a beer gut so as to disguise the fact they are actually a ripped monster"
In reply to EddInaBox:
http://www.needlesports.com/catalogue/content.aspx?con_id=75b7be92-45dd-474...
Used the handy search function, thanks.
Found this, read it twice and then noticed the PS right at the bottom of the article, which does suggest it is a possibility that the fig 8 might invert especially if the ropes are frozen.
Perhaps worth posting the interesting link in future if the question comes up - could save a life. 300N is a worrying low load for a knot to start to fail.
http://www.needlesports.com/catalogue/content.aspx?con_id=75b7be92-45dd-474...
Used the handy search function, thanks.
Found this, read it twice and then noticed the PS right at the bottom of the article, which does suggest it is a possibility that the fig 8 might invert especially if the ropes are frozen.
Perhaps worth posting the interesting link in future if the question comes up - could save a life. 300N is a worrying low load for a knot to start to fail.
In reply to ablackett:
Only testing up to 1000 newtons? What a bizarre article. I exert over 900 newtons before I bounce test or anything.
Only testing up to 1000 newtons? What a bizarre article. I exert over 900 newtons before I bounce test or anything.
In reply to henwardian:
That´s the problem when two threads get muddled together, the tests were for abseiling on two strands where pull-down reliability is a factor and of course one loads each rope equally so 1kN is plenty. When you are abseiling on two ropes joined to extend the length then pull-down is irrelevant and stronger would be better, a double fishermans for example.
That´s the problem when two threads get muddled together, the tests were for abseiling on two strands where pull-down reliability is a factor and of course one loads each rope equally so 1kN is plenty. When you are abseiling on two ropes joined to extend the length then pull-down is irrelevant and stronger would be better, a double fishermans for example.
In reply to ablackett:
My thought is that you can constantly visually monitor a knot on the belay loop, but not the jointing knot at a lower-off.
My thought is that you can constantly visually monitor a knot on the belay loop, but not the jointing knot at a lower-off.
In reply to Chris Craggs: "dingy" = a good example of why pedants live in glass houses. If you're going to pick on people's spelling, at least have the brain to spell your own shit right. It's "dinghy".
In reply to arctic_hobo:
Not according to Auntie!
http://www.bbc.co.uk/news/uk-england-lincolnshire-15179077
> ... It's "dinghy".
Not according to Auntie!
http://www.bbc.co.uk/news/uk-england-lincolnshire-15179077
In reply to Fraser:
My thought is you dont need to. Anyone ever had a fig 8 invert on a belay loop? Yet it happens all the time if you test its use on ab.
My thought is you dont need to. Anyone ever had a fig 8 invert on a belay loop? Yet it happens all the time if you test its use on ab.
In reply to Offwidth:
Good question. I suspect not. If, however, you are worried about it, use another knot or belay off the harness' belay loop.
> (In reply to Fraser)
>
> My thought is you dont need to. Anyone ever had a fig 8 invert on a belay loop?
>
> My thought is you dont need to. Anyone ever had a fig 8 invert on a belay loop?
Good question. I suspect not. If, however, you are worried about it, use another knot or belay off the harness' belay loop.
In reply to EddInaBox: fail - they'd corrected their spelling mistake by the time I read it. Look again.
In reply to ablackett:
I think you have a point. The direction of the forces on the knot could be very similar, if using the rope loop to attach to anchors behind, and belay plate in front. One difference would be the stopper knot, but that's not always used, and often not regarded as necessary.
> Why is it then considered ok to clip into the belay with the rope loop tied with a figure 8 or belay from the rope loop tied with a figure 8? Is there not the same potential for the knot to invert and fail?
>
> Thoughts?
>
> Thoughts?
I think you have a point. The direction of the forces on the knot could be very similar, if using the rope loop to attach to anchors behind, and belay plate in front. One difference would be the stopper knot, but that's not always used, and often not regarded as necessary.
In reply to ablackett:
Our good old stopper knot friend comes to the rescue!
But I don't understand why anyone would want to anchor or belay from the rope loop in normal situations. Much more versatile staying out of the system!
Our good old stopper knot friend comes to the rescue!
But I don't understand why anyone would want to anchor or belay from the rope loop in normal situations. Much more versatile staying out of the system!
Reverse the fig 8, ie thread through backwards so each tail is in line with the long rope, you can then also use stopper knots. It's a bit of a bulky knot but will not roll.
In reply to porridgefan:
Depends what you mean by "normal conditions"....but I would be happy to demonstrate many rescue scenarios where belaying in the rope loop is much more easier and comfortable.
Depends what you mean by "normal conditions"....but I would be happy to demonstrate many rescue scenarios where belaying in the rope loop is much more easier and comfortable.
In reply to ablackett:
Tieing two ropes together with a figure of 8 and tying into your harness are two different uses of a very similar knot.
Anyway, shouldn't you be using a simple overhand knot to abseil on now-a-days :P
Tieing two ropes together with a figure of 8 and tying into your harness are two different uses of a very similar knot.
Anyway, shouldn't you be using a simple overhand knot to abseil on now-a-days :P
In reply to bpmclimb:
Maybe think harder. You are looking at an unlikely combination of the knot aligned perpendicular to the tension, failure to have redundancy and no stopper knot. Its not that its impossible its just that there are so many other factors more likely to be important. Of course it is irresponsible for some not to waer a helmet when belaying at the top of a crag, or use less than 4 pieces each with locking crabs.
Maybe think harder. You are looking at an unlikely combination of the knot aligned perpendicular to the tension, failure to have redundancy and no stopper knot. Its not that its impossible its just that there are so many other factors more likely to be important. Of course it is irresponsible for some not to waer a helmet when belaying at the top of a crag, or use less than 4 pieces each with locking crabs.
In reply to ablackett:
When belaying from the roop loop it would be normal for the rope coming out of the fig8 knot to go to the first (or maybe the only) anchor where it is either tied off or returns to a krab on the rope loop and is tied off there. A force applied to the belay plate attached to the rope loop is therefore putting some direct linear force through the fig8 knot as opposed to pulling in a perpindicular direction as would happen when abseiling on two ropes joined by a fig8.
When belaying from the roop loop it would be normal for the rope coming out of the fig8 knot to go to the first (or maybe the only) anchor where it is either tied off or returns to a krab on the rope loop and is tied off there. A force applied to the belay plate attached to the rope loop is therefore putting some direct linear force through the fig8 knot as opposed to pulling in a perpindicular direction as would happen when abseiling on two ropes joined by a fig8.
In reply to M. Edwards:
Other than a short hoist or a lower to the ground I would usually escape the system. Much easier to do if you are not in the system in the first place. What I tend to do is tie a small overhand on a bight just after my rope loop through my harness and use the OH bight in place of the rope loop. It's just as easy to belay normally or to have the OH further away from the harness and belay in guide mode...
Other than a short hoist or a lower to the ground I would usually escape the system. Much easier to do if you are not in the system in the first place. What I tend to do is tie a small overhand on a bight just after my rope loop through my harness and use the OH bight in place of the rope loop. It's just as easy to belay normally or to have the OH further away from the harness and belay in guide mode...
In reply to porridgefan:
How often do you escape from the system?? I can only remember doing this a few times in my 20+ years of climbing several times a week and well into 5 figures for route numbers. Sitting on the edge of the top of a pitch(the most common belay for me) direct belays are not as easy as indirect belays off the rope loop or harness.
How often do you escape from the system?? I can only remember doing this a few times in my 20+ years of climbing several times a week and well into 5 figures for route numbers. Sitting on the edge of the top of a pitch(the most common belay for me) direct belays are not as easy as indirect belays off the rope loop or harness.
In reply to Offwidth:
The fig 8 (tied in both strands together rather than rethreaded) is generally considered unsafe for joining two ropes for abseil because it can roll. There is a strong consensus to support this, supported by experimental evidence.
My point (and that of the OP, I think) was that in the limiting case described - only a fig. 8 tie-in loop used for both anchors and belay plate, and no stopper knot (not really such an unusual scenario, as anchors and belay plate are supposed to be opposed in direction, and a stopper generally not regarded as necessary for the integrity of the knot) - the forces on the knot will be similar. Why then is the fig 8 tie-in loop almost universally regarded as safe as an attachment point? Why is there no (apparent) tendency for it to roll? I agree with the OP that this is a question worth asking. (I still think this even after thinking further about it).
Your point about redunancy is, I think, not relevant, because the tie-in loop of a fig 8 is not only regarded as safe, but often actively recommended as a superior choice to the harness loop. Yet if the knot were to roll off the end of the rope, the whole system would fail.
Your points about numbers of anchors, use of locking crabs, and the wearing of helmets are all well and good, but don't really shed any light on the particular question raised by the OP.
> (In reply to bpmclimb)
>
> Maybe think harder. You are looking at an unlikely combination of the knot aligned perpendicular to the tension, failure to have redundancy and no stopper knot. Its not that its impossible its just that there are so many other factors more likely to be important. Of course it is irresponsible for some not to waer a helmet when belaying at the top of a crag, or use less than 4 pieces each with locking crabs.
>
> Maybe think harder. You are looking at an unlikely combination of the knot aligned perpendicular to the tension, failure to have redundancy and no stopper knot. Its not that its impossible its just that there are so many other factors more likely to be important. Of course it is irresponsible for some not to waer a helmet when belaying at the top of a crag, or use less than 4 pieces each with locking crabs.
The fig 8 (tied in both strands together rather than rethreaded) is generally considered unsafe for joining two ropes for abseil because it can roll. There is a strong consensus to support this, supported by experimental evidence.
My point (and that of the OP, I think) was that in the limiting case described - only a fig. 8 tie-in loop used for both anchors and belay plate, and no stopper knot (not really such an unusual scenario, as anchors and belay plate are supposed to be opposed in direction, and a stopper generally not regarded as necessary for the integrity of the knot) - the forces on the knot will be similar. Why then is the fig 8 tie-in loop almost universally regarded as safe as an attachment point? Why is there no (apparent) tendency for it to roll? I agree with the OP that this is a question worth asking. (I still think this even after thinking further about it).
Your point about redunancy is, I think, not relevant, because the tie-in loop of a fig 8 is not only regarded as safe, but often actively recommended as a superior choice to the harness loop. Yet if the knot were to roll off the end of the rope, the whole system would fail.
Your points about numbers of anchors, use of locking crabs, and the wearing of helmets are all well and good, but don't really shed any light on the particular question raised by the OP.
In reply to Jimbo C:
A force applied to the belay plate attached to the rope loop is therefore putting some direct linear force through the fig8 knot as opposed to pulling in a perpindicular direction as would happen when abseiling on two ropes joined by a fig8.
Yes that would make the direction of forces differ from the abseil. Although if anchors weren't perfectly equalised, or the belayer had to shift position (perhaps pulled to the side if the second fell) then the rope out of the fig 8 could be slack, with the force taken by anchors connected directly to the tie- in loop. You could then have the 180 degree opposed force scenario.
> (In reply to ablackett)
A force applied to the belay plate attached to the rope loop is therefore putting some direct linear force through the fig8 knot as opposed to pulling in a perpindicular direction as would happen when abseiling on two ropes joined by a fig8.
Yes that would make the direction of forces differ from the abseil. Although if anchors weren't perfectly equalised, or the belayer had to shift position (perhaps pulled to the side if the second fell) then the rope out of the fig 8 could be slack, with the force taken by anchors connected directly to the tie- in loop. You could then have the 180 degree opposed force scenario.
In reply to porridgefan:
I may be wrong, but how I understand your belay set-up you are taking yourself out of helping the belay anchors by by-passing the very helpful resistance your body gives to the anchors. What could be in your case a direct belay set-up. Your belay points have to be bomber for direst belays. Remember sitting down on the ledge adds huge helpful resistance when belaying through the body, and "protects" crap belay points if that's all that can be found. It all goes back to the days when belaying around the waist was the norm, they knew back then what worked, and their ideas can work today in a more modern set-up too. ML covers a small amount of this too. Its all about putting your body into the system as much as possible to protect and increase the value of your belay anchors at the end of the day.
I may be wrong, but how I understand your belay set-up you are taking yourself out of helping the belay anchors by by-passing the very helpful resistance your body gives to the anchors. What could be in your case a direct belay set-up. Your belay points have to be bomber for direst belays. Remember sitting down on the ledge adds huge helpful resistance when belaying through the body, and "protects" crap belay points if that's all that can be found. It all goes back to the days when belaying around the waist was the norm, they knew back then what worked, and their ideas can work today in a more modern set-up too. ML covers a small amount of this too. Its all about putting your body into the system as much as possible to protect and increase the value of your belay anchors at the end of the day.
In reply to Jimbo C:
not in the fairly normal case when the anchors are above your waist height and some one falls off leading with bomber gear already placed.
> (In reply to ablackett)
>
> When belaying from the roop loop it would be normal for the rope coming out of the fig8 knot to go to the first (or maybe the only) anchor where it is either tied off or returns to a krab on the rope loop and is tied off there. A force applied to the belay plate attached to the rope loop is therefore putting some direct linear force through the fig8 knot as opposed to pulling in a perpindicular direction as would happen when abseiling on two ropes joined by a fig8.
>
> When belaying from the roop loop it would be normal for the rope coming out of the fig8 knot to go to the first (or maybe the only) anchor where it is either tied off or returns to a krab on the rope loop and is tied off there. A force applied to the belay plate attached to the rope loop is therefore putting some direct linear force through the fig8 knot as opposed to pulling in a perpindicular direction as would happen when abseiling on two ropes joined by a fig8.
not in the fairly normal case when the anchors are above your waist height and some one falls off leading with bomber gear already placed.
In reply to bpmclimb:
"Why is there no (apparent) tendency for it to roll?"
It's fairly well known as long as one of the strands out of the figure of eight loop is loaded then the loop is safe to cross load across the knot and the knot won't roll easily at all.
As I point out above I fail to see how this is the case unless every belay you set up you have one anchor set for an upward pull, which I've read isn't always advisable as can put unnecessary force in to the system instead of letting the belayer move up a bit.
Personaly I think if you are belaying from the figure of eight loop I think you should tie a stopper knot.
There must be a reason why this knot doesn't invert so easily in the tie in situation, I'm guessing may be something to do with the added friction of going through the harness tie in points on one side of the loop or something.
"Why is there no (apparent) tendency for it to roll?"
It's fairly well known as long as one of the strands out of the figure of eight loop is loaded then the loop is safe to cross load across the knot and the knot won't roll easily at all.
As I point out above I fail to see how this is the case unless every belay you set up you have one anchor set for an upward pull, which I've read isn't always advisable as can put unnecessary force in to the system instead of letting the belayer move up a bit.
Personaly I think if you are belaying from the figure of eight loop I think you should tie a stopper knot.
There must be a reason why this knot doesn't invert so easily in the tie in situation, I'm guessing may be something to do with the added friction of going through the harness tie in points on one side of the loop or something.
In reply to M. Edwards:
I don't really buy this, belaying off your belay loop (rather than your tie in loop) is still a loop to your tie in attachment points on your harness. As your tie in loop is also attached to here I can't see how you are really helping your belay anchors all that much if at all in this senario and either way would be classifed as an indirect belay.
Can you explain a common senario where belaying from your belay loop is significantly easier to escape the system than belaying from your tie in loop? I'm struggling to think of one myself.
I don't really buy this, belaying off your belay loop (rather than your tie in loop) is still a loop to your tie in attachment points on your harness. As your tie in loop is also attached to here I can't see how you are really helping your belay anchors all that much if at all in this senario and either way would be classifed as an indirect belay.
Can you explain a common senario where belaying from your belay loop is significantly easier to escape the system than belaying from your tie in loop? I'm struggling to think of one myself.
In reply to CurlyStevo:
Try the two set ups sometime, sitting on the edge of a crag with the anchors behind you and someone hanging on the rope. Using the harness belay loop rather than the rope loop really does allow you to take an amazing amount of the load off the anchors.
The only reason for using the rope loop is to transfer the load more directly to the anchors, increasing the belayer's comfort, but this should obviously only be done if the anchors are totally bomber.
> (In reply to M. Edwards)
> I don't really buy this, belaying off your belay loop is still a loop to your tie in attachment points on your harness. As your tie in loop is also attached to here I can't see how you are really helping your belay anchors all that much.
> I don't really buy this, belaying off your belay loop is still a loop to your tie in attachment points on your harness. As your tie in loop is also attached to here I can't see how you are really helping your belay anchors all that much.
Try the two set ups sometime, sitting on the edge of a crag with the anchors behind you and someone hanging on the rope. Using the harness belay loop rather than the rope loop really does allow you to take an amazing amount of the load off the anchors.
The only reason for using the rope loop is to transfer the load more directly to the anchors, increasing the belayer's comfort, but this should obviously only be done if the anchors are totally bomber.
http://www.ukclimbing.com/articles/page.php?id=1129
Explores most of the questions posed in this thread.
In reply to ablackett:
Is there not the same potential for the knot to invert and fail?
No. The difference is tails vs loop. Even if you assume the knot is somehow going to unroll every time, the loop is (hopefully) clipped into something planet sized which can't pass the knot, whereas the tails aren't.
Is there not the same potential for the knot to invert and fail?
>
No. The difference is tails vs loop. Even if you assume the knot is somehow going to unroll every time, the loop is (hopefully) clipped into something planet sized which can't pass the knot, whereas the tails aren't.
In reply to robinsi197:
I don't follow your logic:
"The difference is tails vs loop."
Not really pulling a fig 8 loop apart is very similar to pulling on either end of two ropes joined by a fig 8 the only notable different in the way the knot is being pulled apart is the friction at the tie in points on your harness the angle across the knot is still the same. if the pull is not on the actual knot.
"the loop is (hopefully) clipped into something planet sized which can't pass the knot"
Can you explain what you mean?
- What about belaying just from the rope loop from the ground with no anchors?
- What if the anchors are above your wasit and the belayer gets lifted up so the anchor rope is slack, I can see the knot rolling of the end of the tail still.
Stevo
I don't follow your logic:
"The difference is tails vs loop."
Not really pulling a fig 8 loop apart is very similar to pulling on either end of two ropes joined by a fig 8 the only notable different in the way the knot is being pulled apart is the friction at the tie in points on your harness the angle across the knot is still the same. if the pull is not on the actual knot.
"the loop is (hopefully) clipped into something planet sized which can't pass the knot"
Can you explain what you mean?
- What about belaying just from the rope loop from the ground with no anchors?
- What if the anchors are above your wasit and the belayer gets lifted up so the anchor rope is slack, I can see the knot rolling of the end of the tail still.
Stevo
In reply to Robert Durran:
"Try the two set ups sometime, sitting on the edge of a crag with the anchors behind you and someone hanging on the rope. Using the harness belay loop rather than the rope loop really does allow you to take an amazing amount of the load off the anchors."
but how does this help? assumedly you still need to tie off the climber to the anchors in some way and then untie your self. I can't see how the attachment your harness makes much difference here.
"The only reason for using the rope loop is to transfer the load more directly to the anchors, increasing the belayer's comfort, but this should obviously only be done if the anchors are totally bomber. "
Not really it's also to stop you being moved about quite as much and also squashed by the rope for example if your second slips or the leader takes a factor 2. Also in the case for example where you are standing up on a ledge with anchors above your waist clipping the belay device to your rope loop or your belay loop is going to me very little (zero?) difference to the loading on the anchors.
I think in the general case it's not going to make much difference, both setups are an indirect belay although I realise in practice there isn't a tonne of difference between some setups of indirect belay and direct belaying depends how in line (and tight) the ropes to the anchors are compared with the belayers position is and the direction of pull on the loaded rope.
"Try the two set ups sometime, sitting on the edge of a crag with the anchors behind you and someone hanging on the rope. Using the harness belay loop rather than the rope loop really does allow you to take an amazing amount of the load off the anchors."
but how does this help? assumedly you still need to tie off the climber to the anchors in some way and then untie your self. I can't see how the attachment your harness makes much difference here.
"The only reason for using the rope loop is to transfer the load more directly to the anchors, increasing the belayer's comfort, but this should obviously only be done if the anchors are totally bomber. "
Not really it's also to stop you being moved about quite as much and also squashed by the rope for example if your second slips or the leader takes a factor 2. Also in the case for example where you are standing up on a ledge with anchors above your waist clipping the belay device to your rope loop or your belay loop is going to me very little (zero?) difference to the loading on the anchors.
I think in the general case it's not going to make much difference, both setups are an indirect belay although I realise in practice there isn't a tonne of difference between some setups of indirect belay and direct belaying depends how in line (and tight) the ropes to the anchors are compared with the belayers position is and the direction of pull on the loaded rope.
In reply to CurlyStevo:
Have you actually tried it? It might seem surprising, but it really does make quite a big difference.
Are you talking about escaping the system? If so, it really makes no difference whether you are belaying off the rope loop or the harness loop.
Precisely. That is what I am saying. But if the anchors are in any way suspect, much better that you are moved about and squashed a bit than that the anchors fail. In the end it's a judgement call.
Not tried that. I suspect you might be surprised.
> (In reply to Robert Durran)
> "Try the two set ups sometime, sitting on the edge of a crag with the anchors behind you and someone hanging on the rope. Using the harness belay loop rather than the rope loop really does allow you to take an amazing amount of the load off the anchors."
> "Try the two set ups sometime, sitting on the edge of a crag with the anchors behind you and someone hanging on the rope. Using the harness belay loop rather than the rope loop really does allow you to take an amazing amount of the load off the anchors."
Have you actually tried it? It might seem surprising, but it really does make quite a big difference.
>
> but how does this help? assumedly you still need to tie off the climber to the anchors in some way and then untie your self. I can't see how the attachment your harness makes much difference here.
> but how does this help? assumedly you still need to tie off the climber to the anchors in some way and then untie your self. I can't see how the attachment your harness makes much difference here.
Are you talking about escaping the system? If so, it really makes no difference whether you are belaying off the rope loop or the harness loop.
>
> "The only reason for using the rope loop is to transfer the load more directly to the anchors, increasing the belayer's comfort, but this should obviously only be done if the anchors are totally bomber. "
>
> Not really it's also to stop you being moved about quite as much and also squashed by the rope for example if your second slips or the leader takes a factor 2.
> "The only reason for using the rope loop is to transfer the load more directly to the anchors, increasing the belayer's comfort, but this should obviously only be done if the anchors are totally bomber. "
>
> Not really it's also to stop you being moved about quite as much and also squashed by the rope for example if your second slips or the leader takes a factor 2.
Precisely. That is what I am saying. But if the anchors are in any way suspect, much better that you are moved about and squashed a bit than that the anchors fail. In the end it's a judgement call.
> Also in the case for example where you are standing up on a ledge with anchors above your waist clipping the belay device to your rope loop or your belay loop is going to me very little (zero?) difference to the loading on the anchors.
Not tried that. I suspect you might be surprised.
In reply to ablackett: If I thought that the anchors were so poor that a belay from the belay loop would be better than the rope loop I would be tempted to use a waist belay. Thankfully I have not encountered many belays that poor.
Al
Al
In reply to CurlyStevo:
My understanding of the original question was that it was comparing tying two ropes together for abseil as follows :
"The two ends you want to join
are held parallel with the ends "pointing" in the same direction. You grab
both ropes together and then tie a regular single fig-eight knot in both
ropes at once." <taken from an accident report> i.e. using a figure of 8 as you would use an overhand for abseiling,
and the situation when you belay by tying yourself to an anchor using a loop of your rope (between you and your mate) using a figure of 8 knot clipped into the anchor point (rather than the clove hitch more commonly used these days).
Clearly in the second case, no amount of unrolling is going to unclip the rope from the anchor (screwgate), you're still tied to one end and your mate's still tied to the other.
My understanding of the original question was that it was comparing tying two ropes together for abseil as follows :
"The two ends you want to join
are held parallel with the ends "pointing" in the same direction. You grab
both ropes together and then tie a regular single fig-eight knot in both
ropes at once." <taken from an accident report> i.e. using a figure of 8 as you would use an overhand for abseiling,
and the situation when you belay by tying yourself to an anchor using a loop of your rope (between you and your mate) using a figure of 8 knot clipped into the anchor point (rather than the clove hitch more commonly used these days).
Clearly in the second case, no amount of unrolling is going to unclip the rope from the anchor (screwgate), you're still tied to one end and your mate's still tied to the other.
In reply to Gaston Rubberpants:
must say I agree, the only times I have a belay I don't trust I body belay, belaying from the belay loop is not likely to make a significant difference.
must say I agree, the only times I have a belay I don't trust I body belay, belaying from the belay loop is not likely to make a significant difference.
In reply to robinsi197:
I see people are still either misunderstanding the set-up or counting angels on pinheads. Just tie a stopper knot and all the miniscule risk has gone.
I see people are still either misunderstanding the set-up or counting angels on pinheads. Just tie a stopper knot and all the miniscule risk has gone.
In reply to robinsi197:
"Clearly in the second case, no amount of unrolling is going to unclip the rope from the anchor (screwgate), you're still tied to one end and your mate's still tied to the other."
incorrect it can still potentially roll far enough the tail is no longer in the knot (as long as the attachement to the anchors is not loaded, this could happen if the belayer gets pulled up and the anchors ae above him/her) at this point there is a single figure of eight in the rope back to the anchors which passes through your tie in points but does not rethread the figure of eight and the belay device is just passing through this loose single piece of rope.
Also as I mention what about belaying from a tie in knot when it is not attached to any anchors.
Anyway I think it is quite an acedemic point as offwidth mentions it's not a known issue for some reason, why is the question, as it certainly could happen with the low failure loads of the knot.. I still think a stopper knot is a good idea after a figure of 8 if you are belaying from the tie in loop.
"Clearly in the second case, no amount of unrolling is going to unclip the rope from the anchor (screwgate), you're still tied to one end and your mate's still tied to the other."
incorrect it can still potentially roll far enough the tail is no longer in the knot (as long as the attachement to the anchors is not loaded, this could happen if the belayer gets pulled up and the anchors ae above him/her) at this point there is a single figure of eight in the rope back to the anchors which passes through your tie in points but does not rethread the figure of eight and the belay device is just passing through this loose single piece of rope.
Also as I mention what about belaying from a tie in knot when it is not attached to any anchors.
Anyway I think it is quite an acedemic point as offwidth mentions it's not a known issue for some reason, why is the question, as it certainly could happen with the low failure loads of the knot.. I still think a stopper knot is a good idea after a figure of 8 if you are belaying from the tie in loop.
In reply to CurlyStevo:
"you're still tied to one end and your mate's still tied to the other"
What tail? Tying to the anchor using a loop, just like you would with a clove hitch.
"you're still tied to one end and your mate's still tied to the other"
What tail? Tying to the anchor using a loop, just like you would with a clove hitch.
In reply to robinsi197:
ahhhhhh, I believe the OP and most/all other people on this thread are talking about belaying FROM you fig eight TIE IN loop, if indeed you are attaching to anchors for the purposes of this discussion the knot at that end as long as it's secure is irrelevent (well as far as I can work out anyways).
> (In reply to CurlyStevo)
>
> "you're still tied to one end and your mate's still tied to the other"
>
> What tail? Tying to the anchor using a loop, just like you would with a clove hitch.
>
> "you're still tied to one end and your mate's still tied to the other"
>
> What tail? Tying to the anchor using a loop, just like you would with a clove hitch.
ahhhhhh, I believe the OP and most/all other people on this thread are talking about belaying FROM you fig eight TIE IN loop, if indeed you are attaching to anchors for the purposes of this discussion the knot at that end as long as it's secure is irrelevent (well as far as I can work out anyways).
In reply to CurlyStevo:
Yes, I think we've been in this kind of argument before
I read "Why is it then considered ok to clip into the belay with the rope loop tied with a figure 8" meaning the knot at the anchor point, not the harness. We used to use figure of 8s regularly for that until the adjustability advantage of the clove hicth was pointed out.
> ahhhhhh, I believe the OP and most/all other people on this thread are talking about belaying FROM you fig eight TIE IN loop, if indeed you are attaching to anchors for the purposes of this discussion the knot at that end as long as it's secure is irrelevent (well as far as I can work out anyways).
Yes, I think we've been in this kind of argument before
I read "Why is it then considered ok to clip into the belay with the rope loop tied with a figure 8" meaning the knot at the anchor point, not the harness. We used to use figure of 8s regularly for that until the adjustability advantage of the clove hicth was pointed out.
In reply to robinsi197:
if we could draw pictures on the thread it would make life a LOT easier sometimes
if we could draw pictures on the thread it would make life a LOT easier sometimes
In reply to CurlyStevo:
Yes, you're correct. I was only considering the belaying of the second. For me, this discussion highlights that it's good practice to clip the harness belay loop as well as the rope loop(s).
> (In reply to Jimbo C)
> [...]
>
> not in the fairly normal case when the anchors are above your waist height and some one falls off leading with bomber gear already placed.
> [...]
>
> not in the fairly normal case when the anchors are above your waist height and some one falls off leading with bomber gear already placed.
Yes, you're correct. I was only considering the belaying of the second. For me, this discussion highlights that it's good practice to clip the harness belay loop as well as the rope loop(s).
In reply to Jimbo C:
This thread is one of the most confusing I've ever read. I'm not going to worry about a solution until I can understand which problem is being discussed!
Is the concern about the fig 8 harness tie-in and belaying from the rope loop - so the fig 8 might be cross loaded at 180 degrees between an anchor attachment and the belay device?
- I can see that the loading in this situation might be similar to that on a fig8 joining two ropes, but I would have thought that a decent large stopper knot would prevent inverting of the fig8.
or
Is the concern about tying into an anchor with a fig8 on a rope end? - in which case there can't be a proper 180 degree crossload on the knot, as the anchor pull will be on the loop and the other pull is on the rope going from the belayer to the knot), and I can't see much of a problem provided the free end of rope isn't too short and there is a stopper knot.
or
Is the concern about tying into an anchor with a fig8 on a bight of rope (so out to anchor from belayer to fig8 and then back to belayer, both ends secured at belayer)? - in which case both ropes will go back to the belayer from the knot and it would be impossible for the knot to undo no matter what!
This thread is one of the most confusing I've ever read. I'm not going to worry about a solution until I can understand which problem is being discussed!
Is the concern about the fig 8 harness tie-in and belaying from the rope loop - so the fig 8 might be cross loaded at 180 degrees between an anchor attachment and the belay device?
- I can see that the loading in this situation might be similar to that on a fig8 joining two ropes, but I would have thought that a decent large stopper knot would prevent inverting of the fig8.
or
Is the concern about tying into an anchor with a fig8 on a rope end? - in which case there can't be a proper 180 degree crossload on the knot, as the anchor pull will be on the loop and the other pull is on the rope going from the belayer to the knot), and I can't see much of a problem provided the free end of rope isn't too short and there is a stopper knot.
or
Is the concern about tying into an anchor with a fig8 on a bight of rope (so out to anchor from belayer to fig8 and then back to belayer, both ends secured at belayer)? - in which case both ropes will go back to the belayer from the knot and it would be impossible for the knot to undo no matter what!
In reply to Charlie_Zero:
I got the impression that the OP and several others were talking about the first situation you mention. As you say, there is no potential for 'cross loading' the fig8 in the other 2 scenarios.
I got the impression that the OP and several others were talking about the first situation you mention. As you say, there is no potential for 'cross loading' the fig8 in the other 2 scenarios.
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