Rigging anchor configuration

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 Osiris 14 Apr 2021

Saw someone at Auchinstarry today had rigged a top rope anchor with nothing but the rope (two anchors with an in line knot). Trying to figure out exactly how, I came across this. However, it is self equalising with the rope running across the rope so it can't be right, as presumably the friction would be quite dangerous when weighted. I hope you can understand what I'm trying to get at. Can someone please show me how to set this up (using nothing but the rope). Cheers.

Post edited at 22:09

 AndyRoss 14 Apr 2021
In reply to Osiris:

Likely tied off to one anchor point, and then the loop of an alpine butterfly clipped to the other. See https://www.vdiffclimbing.com/alpine-butterfly/ for details.

 tehmarks 14 Apr 2021
In reply to Osiris:

Generalising from your specific query, I quite often rig topropes (bottom ropes*) with just the climbing rope, if the rope is long enough. Rig it with one end just like you were making a trad anchor, but to an alpine butterfly rather than your rope loop, rope down the crag and back up, through the anchor and down again to the climber. It can be a pain in the rear end on account of the extra bit of rope going down the crag, but it does work.

Post edited at 22:27
 jkarran 14 Apr 2021
In reply to Osiris:

There are several ways of doing it. The one you show fails the 'inextensible' test, if one point fails you fall quite a way.

It really depends what you're faced with but a simple option if you're tied into the rope is: walk round a tree then back to the edge. Tie the tree rope back to your tie in with a fig8 on the bight. Take the tale of that 8 to another tree, pass it aroubd the tree then drag the loop back to the edge. Repeat tying the loose strand into your tie in.

If you just want to rig a Y hang: knot the end of the rope to a tree. Near the cliff edge form a large bight with an overhand. Take that bight to another tree and tie it off. Bowlines on the trees are easiest.

Jk

 JoshOvki 14 Apr 2021
In reply to AndyRoss:

This is how I would go about it 

1
In reply to Osiris:

What AndyRoss says. It's becoming my standard approach with Pembroke ab stakes.

I don't know what you call that thing in the photo but that gets a big nope from me. If you don't know knots, tie lots.

Post edited at 23:11
 tehmarks 14 Apr 2021
In reply to Longsufferingropeholder:

> If you don't know knots, tie lots.

Or the better version: if you don't know knots, go and educate yourself! Doesn't have the same ring to it though.

3
 Andy Hardy 15 Apr 2021
In reply to Osiris:

If the anchor on the left fails, does the whole thing fail?

 gravy 15 Apr 2021
In reply to AndyRoss:

Same here except I use an overhand knot instead of an alpine butterfly.

 summo 15 Apr 2021
In reply to AndyRoss:

> Likely tied off to one anchor point, and then the loop of an alpine butterfly clipped to the anchor.

It's that or bowline on the bight, creating two loops to clip in, used by many caving. 

Op; 

The picture shows neither of these. The left hand anchor isn’t isolated from the other. 

 CantClimbTom 15 Apr 2021
In reply to gravy:

Learn an alpine butterfly it's a lot better, especially when you need to untie it!

Fig 8 on end for one anchor and alpine to second anchor, then adjust to equalise

I'm a strong believer that this isn't the sea-scouts or something and we don't need to learn lots and lots of fancy knots, we just need to know a few basic ones. After climbing on and off for 25 years, mine/caves, and a few years rope access, I'm sure you can very easily and efficiently work with only figure 8, alpine butterfly, fisherman's knot and for emergencies Italian hitch and french/standard prussic.

All the rest of the knots are useful in their places, but not essential. Just my opinion...

1
 AlanLittle 15 Apr 2021
In reply to Andy Hardy:

Certainly looks like it. Unless the left hand knot by some unlikely miracle jams in the little bight it's threaded through, instead of either just pulling straight through or sawing through the rope.

 john arran 15 Apr 2021
In reply to Osiris:

I'm a big fan of keeping it simple. With few exceptions, I tend only to use fig-8, bowline and clove hitches (on karabiners) and I never have a problem coming up with a quick and safe arrangement.

In your example, I'd just tie the end of the end of the rope to one anchor with a bowline, tie a simple fig-8 at the Y junction, then simply tie another bowline at the other anchor with a bight.

It's hard to see how other arrangements could be much quicker or safer. Alpine butterflies and some other knots can be good if you use them often, but they're far from essential and if there's any chance at all that you may make a mistake tying one (maybe because you don't do so often, you're tired and rushed because a storm is coming in) then sticking with the absolute basics is best.

 Jamie Wakeham 15 Apr 2021
In reply to CantClimbTom:

I'd want to add the clove hitch to that list; I think I'd struggle without it.  It's also the only one I can tie one handed!

 gravy 15 Apr 2021
In reply to CantClimbTom:

I know how to tie an alpine butterfly, however, I prefer the overhand simply because it's superfast, easier to estimate the length needed to equalise the anchors and easier to adjust. 

I'll admit:

- the AB is easier to untie if it has been heavily loaded but 99% of the time this is not an issue.

- the AB looks neater and more "professional"

I'll use a bowline for the loose end if it is tied around something (tree, boulder, thread) and a f-8 on a bight if it's clipping to gear because, in each context, they are fast, faff free, easy to adjust, easy to check and reliable.

OP Osiris 17 Apr 2021
In reply to Osiris:

Some great ideas here, but just to keep it on topic. I said the climber had used nothing but the rope and an in-line knot to form an anchor. The anchor was a rail, so there's no way to sling a loop onto it, which means it surely had to include an in-line knot. The diagram shows the set up. I've tried a couple things and I think it must have been either a bowline or a rethreaded overhand. The over hand seems better as it seems less likely to roll in the event of an anchor failure. Anyone have any other ideas?

Post edited at 14:01
OP Osiris 17 Apr 2021
In reply to Osiris:

Diagram below.


 Cornish boy 17 Apr 2021
In reply to Jamie Wakeham:

> I'd want to add the clove hitch to that list; I think I'd struggle without it.  It's also the only one I can tie one handed!

Totally agree with you Jamie. It’s also really easy to adjust. 

Post edited at 14:09
OP Osiris 17 Apr 2021
In reply to Osiris:

The photo upload is too buggy to use, so just imagine tying an overhand/bowline passing the end around an anchor (in this case the rail) then finishing/re-threading the knot with it, then the tail is tied round the second anchor.

Post edited at 14:10
 CantClimbTom 17 Apr 2021
In reply to Jamie Wakeham:

Thanks, you're right.

I'm meant to include clove hitch but had a stupid-moment and didn't type it

 Howard J 17 Apr 2021
In reply to Osiris:

You could use a directional Figure 8, where the working end emerges from the knot opposite the standing end, rather than lying parallel as in the normal Fig 8.   

https://climbtallpeaks.com/figure-8-knot-uses-for-climbing/#26-figure-8-dir...

The video shows one way of tying it, but you can also re-thread it (it's just an incomplete version of the standard Fig-8).   Tie a single 8 in the rope as with a standard re-threaded knot, make a loop around one anchor and partially rethread the Fig 8 leaving the working end emerging at the top of the knot.  You then take this end back to the other anchor and tie off with a clove hitch.

 craig h 17 Apr 2021
In reply to Osiris:

Fabric on fabric is not a good way of rigging or potential outcome, a static load you may get away with, but any dynamic loading or chance of angle when loaded would not be good.

A simple Y-hang would eliminate this plus a carabiner at the touch point between the 2 ropes. Personally I'd have used a figure of 8 (or 9) and an Alpine butterfly to equalise the load, keeping the angle between anchors at least below 120 degrees, closer to 90 or less if possible.

1
In reply to Osiris:

One way I'd approach it: Take 1 end of the rope and tie around the first anchor using a re-threaded figure 8/overhand or a bowline. Take the remaining end of the rope and tie around the second anchor using the same method as anchor 1. Safety approach the crag edge (preferably attached to something) with both strands of rope going to the anchors. Create a bight of rope and lower it down to where you want to top rope to end. When you have the correct length, tie an overhand or figure 8 around all strands. Tie another figure 8 or figure 9 at the end of the bight and attach screwgates for top rope to run through. The left over rope is coiled neatly at the top. 

Post edited at 19:38

OP Osiris 17 Apr 2021
In reply to Osiris:

I appreciate all the ideas... You can stop now! Fabric on fabric is obviously dangerous and I did say that. It was merely the first results of my experimentation at 2300 last night. I wanted to know exactly how to replicate the exact set up of knot I saw (see diagram) and after further experimentation the answer is that it was an in line overhand or bowline or, as Howard J said, could be a partially rethreaded figure 8. Thank you and goodnight!

4
 craig h 17 Apr 2021
In reply to Osiris:

Keep it simple and you keep it safe, learn how to tie an Alpine Butterfly to equalise the load between 2 anchor points. 

In reply to Osiris:

There's nothing that rules out tying a butterfly with a rope end. You could tie an overhand in the rope, pass the end round your rail, tie through the overhand to create a butterfly, then fig 8 to your other post or whatever.

Imagine you do this: https://www.netknots.com/rope_knots/alpine-butterfly-bend blue first, then round the thing, then orange backwards, then off to anchor 2.

OP Osiris 19 Apr 2021
In reply to Longsufferingropeholder:

Ah. Very good! I'll try that sometime. Thank you.

Post edited at 08:29
 jkarran 19 Apr 2021
In reply to Osiris:

> Diagram below.

That works if you have two anchors very close together (eg staples) and the patience to re-thread the knots.

To view the problem differently and make it easier/quicker to solve in real world situations you need to consider a bight of rope can be treated, in most circumstances, exactly like a single strand. Bights can be re-threaded into an existing (single or multi strand) knot and knots can be formed on bights. For example the right hand (bight) branch doesn't need to pass round the post, it could be tied to the post with a bowline or a very bulky re-threaded 8/overhand.

jk

In reply to Osiris:

> Ah. Very good! I'll try that sometime. Thank you.

Found a better demo for you. How to use in this very context halfway down here: https://www.ropelab.com.au/the-awesome-alpine-butterfly/
(Scroll to "rethreaded alpine butterfly")

Post edited at 15:03
 deepsoup 20 Apr 2021
In reply to Longsufferingropeholder:

It's a beautiful knot, but 'awesome'?  Nah, that's laying it on a bit thick.  I mean apart from looking all fancy schmancy does it really offer anything that the humble overhand can't do equally well? Really?

Also, having once well and truly welded one in to the middle of a rigging rope as part of an improvised slackline set up I suspect it's a bit of a myth that it's any easier to untie than an overhand after being heavily loaded

And that photo half way down where it's been used to join two different ropes with a double fisherman's knot in the 'loop' - why on earth would you do that?  (Other than that you just really really want to use an Alpine Butterfly.)

1
In reply to deepsoup:

> It's a beautiful knot, but 'awesome'?  Nah, that's laying it on a bit thick.  I mean apart from looking all fancy schmancy does it really offer anything that the humble overhand can't do equally well? Really?

Awesome is subjective, but it is bloody useful.

> Also, having once well and truly welded one in to the middle of a rigging rope as part of an improvised slackline set up I suspect it's a bit of a myth that it's any easier to untie than an overhand after being heavily loaded

Try undoing an overhand you've slacklined on! lol.

> And that photo half way down where it's been used to join two different ropes with a double fisherman's knot in the 'loop' - why on earth would you do that?  (Other than that you just really really want to use an Alpine Butterfly.)

Tells you in the caption.

Post edited at 15:35
2
 maxsmith 20 Apr 2021
In reply to deepsoup:

I actually have to defend the alpine buttefly here, it is amazing! particularly for rigging scenarios like this one, tying on the middle of a rope of three or for any use where a knot will get loaded heavily (i.e. top roping).

I suspect  many people dislike the alpine butterfly because they have only been taught the 'finger wrap' method of tying it. I find it hard to create a large bight with this method, and pulling slack through the knot quickly can collapse it.  This is pretty annoying as most of the best uses for the knot require a relatively large bight. 

I now use the 'twist' method and find it a lot quicker more user friendly - easy to create a bight of any length.  

 deepsoup 20 Apr 2021
In reply to Longsufferingropeholder:

> Try undoing an overhand you've slacklined on!

Have done*.  I don't think it's really that much harder, if at all, as long as the knot was neatly dressed with the strands all parallel to begin with.  The bit that pulls tight is the 'inner' overhand in both knots (as you can see very clearly from the 'rethreaded' demonstration on that website, the AB is itself a variation on an overhand knot, it's just 'rethreaded' in a different less straightforward way).

Oh, speaking of which..  a bit further up the page he cautions against not having the 'wings' interlocked.  ("#3")  The bit that bakes my noodle about trying to re-thread an AB is not doing that, but he doesn't address that at all in the demo of how to tie a rethreaded AB, you can't even see whether he has or not.

> lol.

Glad you're enjoying yourself.  I'm here all week.  Try the fish.

> Tells you in the caption.

It does, but it still doesn't seem like a particularly sensible way to go about joining two ropes, and if you were anticipating wanting a loop to clip while passing the knot it seems slightly bizarre that you'd choose to have a honking great double-fishermans right in the middle of that loop.

*(But not often.  Obviously, if a knot is going to be loaded very heavily and needs to be easy to untie again afterwards a bowline is probably the way to go.)

In reply to deepsoup:

> Have done*.  I don't think it's really that much harder, if at all, as long as the knot was neatly dressed with the strands all parallel to begin with.  The bit that pulls tight is the 'inner' overhand in both knots (as you can see very clearly from the 'rethreaded' demonstration on that website, the AB is itself a variation on an overhand knot, it's just 'rethreaded' in a different less straightforward way).

It's just 2 overhands tied through each other. Once you see it like that the rethreaded version is way easier to reproduce. (I find anyway)

> Oh, speaking of which..  a bit further up the page he cautions against not having the 'wings' interlocked.  ("#3")  The bit that bakes my noodle about trying to re-thread an AB is not doing that, but he doesn't address that at all in the demo of how to tie a rethreaded AB, you can't even see whether he has or not.

Pretty clear that he has but yeah, maybe he should have made a bigger deal of that.

> It does, but it still doesn't seem like a particularly sensible way to go about joining two ropes

Yeah, I wouldn't use it for that. But I'm not going to have a go at the guy for writing a webpage with all the potential uses.

When I have two stakes and one ab rope it's the knot I use. Otherwise, not so much. But other people do different things and might have many different use cases.

 deepsoup 20 Apr 2021
In reply to maxsmith:

> I actually have to defend the alpine buttefly here, it is amazing!

You don't have to defend it from me! I think it's lovely and use it all the time.  (I generally go for the 'twist' method too, like you I find it easier when tying a big loop.)

Thing is I love it because it's so aesthetically pleasing, whereas from a purely functional point of view I'm just not convinced it's really any better than a simple overhand most (perhaps all) of the time. 

Also there are one or two applications where it clearly isn't quite as good as its plain-jane basic boring cousin.  One of which is joining two ropes for an abseil, and another, I would suggest, is as a re-threaded knot that want to be able to tie quickly, easily and reliably right all the time even if you're a bit stressed and/or tired. 

I have taught myself to tie a re-threaded AB several times during my life, because any time I come to do it and haven't practised much recently I find I've forgotten it again.

 deepsoup 20 Apr 2021
In reply to Longsufferingropeholder:

> It's just 2 overhands tied through each other.

Yes, that's precisely my point.  When either an AB or an overhand becomes perma-tied by being overloaded, I suspect that happens by the exact same mechanism.  But at least when it's a simple overhand on the bight it might be marginally easier to 'break' the knot, because the strands are all parallel throughout.

> But I'm not going to have a go at the guy for writing a webpage with all the potential uses.

Even by UKC standards, I think you're being weirdly combative if you think I'm 'having a go' at the guy and getting all huffy and defensive on his behalf.

> When I have two stakes and one ab rope it's the knot I use.

Me too if I'm clipping the loop into a carabiner, or perhaps dropping it over the top of a stake (most likely with a clove hitch in it in that case).

> Otherwise, not so much.

Likewise.  And if the rope itself is going around a tree or the bottom of a fence-post, I certainly wouldn't be aiming to re-thread it unless I'm completely relaxed and happy and have plenty of time.

 EdS 20 Apr 2021
In reply to Osiris:

thats not self equalising its self cutting.

Fig 8 and alpine butterfly or a fusion not --- look up Caving Y hangs

In reply to deepsoup:

> Yes, that's precisely my point.  When either an AB or an overhand becomes perma-tied by being overloaded, I suspect that happens by the exact same mechanism.  But at least when it's a simple overhand on the bight it might be marginally easier to 'break' the knot, because the strands are all parallel throughout.

Not sure about this. I think it's easier to get a butterfly moving but willing to be proven wrong.

> Even by UKC standards, I think you're being weirdly combative if you think I'm 'having a go' at the guy and getting all huffy and defensive on his behalf.

Bad choice of words on my part. I think we're violently agreeing with each other now.

> Me too if I'm clipping the loop into a carabiner, or perhaps dropping it over the top of a stake (most likely with a clove hitch in it in that case).

Yep, and yep. Clove hitch on the back of the stake means it's not coming off. Usually ends up being the hardest part to get undone tbh.

> Likewise.  And if the rope itself is going around a tree or the bottom of a fence-post, I certainly wouldn't be aiming to re-thread it unless I'm completely relaxed and happy and have plenty of time.

Yep, same. I'd normally just use a sling in those cases, but that doesn't fit the OP question.

 deepsoup 20 Apr 2021
In reply to Longsufferingropeholder:

> Not sure about this. I think it's easier to get a butterfly moving but willing to be proven wrong.

It's possible that I'm wrong too, probably quite a close run thing in either case.  I think the Alpine Butterfly that I couldn't untie is still the only knot I've ever completely failed to get undone without destroying the rope though.  (Not that I'd been planning to use it again anyway.)

It's almost worth the effort of setting up an experiment to find out one way or the other.

> I think we're violently agreeing with each other now.

Ha ha, apparently so!

 Pbob 21 Apr 2021
In reply to Osiris:

Absolutely good idea to know how to set up on the climbing rope only but do keep in mind that the dynamic climbing rope could end up 'sawing' back and forth across edges (especially if the anchor points are a long way back) risking a best erosion of the edge and at worst abrading the rope. For top or bottom roping best to carry a short length (5-10m) of eg 9mm static cord. Apologies for stating the obvious.

 GazzerM61 21 Apr 2021
In reply to Andy Hardy:

> If the anchor on the left fails, does the whole thing fail?

Yes catastrophic fail!

 LastBoyScout 22 Apr 2021
In reply to CantClimbTom:

>  I'm sure you can very easily and efficiently work with only figure 8, alpine butterfly, fisherman's knot and for emergencies Italian hitch and french/standard prussic. + clove hitch.

> All the rest of the knots are useful in their places, but not essential. Just my opinion...

I'd add bowline - I use it a lot for climbing walls, as saves a lot of time to tie and easier to undo after being loaded.

I also find it a more compact knot when instructing kids - especially with high tie-in points, like you get on full-body harnesses. The Fig. 8 + stopper knot has a good chance of them getting hit in the face by the stopper knot.

 LastBoyScout 22 Apr 2021
In reply to Pbob:

> Absolutely good idea to know how to set up on the climbing rope only but do keep in mind that the dynamic climbing rope could end up 'sawing' back and forth across edges (especially if the anchor points are a long way back) risking a best erosion of the edge and at worst abrading the rope. For top or bottom roping best to carry a short length (5-10m) of eg 9mm static cord. Apologies for stating the obvious.

Or a bit of old carpet, or anything else to protect the edge. Don't forget to tie it so it can't fall on anyone!

 CantClimbTom 09 May 2021
In reply to Osiris:

If you need a small rope protector few things are as good as a rubber car floor mat. Next time you're in someone else's car, take the mat, punch (not cut the sides need to be clean and round or it'll rip) a hole and tie a shoelace or something to it. Perfect!


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