UKC

Other than for moving together and bringing 2 seconds up when else does this prove useful in trad climbing (maybe never eh, the clue is in the name i guess!) or all forms of climbing?

Cheers!

In reply to Wilbur: if you damage yer rope you can isolate it with an apline butterfly so no load is place on the f*cked bit.

In reply to Dr Avid:

does an figure of eight on a bight do this too?

In reply to Wilbur:

Improvised etrier for when that trad route becomes an aid route

In reply to JackKeen: Thats what I thought, but an AB is designed for a three way pull, so I guess its better suited to having the two ends of the roped pulled from either end.

In reply to Wilbur:

Useful for equalising anchors (as an alternative to overhand or fig 8) when say belays are a long way back and far apart.

Also a common knot for SRT rigging in caving due to being easy to adjust and loadable both sides.

In reply to JackKeen:

Fig of 8 on the bight isn't desinged for that. Technically it could rollover and deform. Alpine butterfly can take a pull in 3 directions.

Used to use it a lot for making traverses in caving and improvised rope ladders.

cheers
mark

In reply to Wilbur:

I'd say not often.

The isolation of a duff bit of rope is useful but then leads to other problems - how are you going to pass said duff bit? As a quick fix it serves that purpose but you'd soon want to find a more permanent solution.

The three way load often cited is also over stated i.e. moving together etc. If you have three people in a line, the one in the middle attached with an AB; if used as a means of bringing up this second person the knot is effectively an end loop - a role for which this knot isn't the best option... that would be an end loop knot i.e. fig 8 or overhand etc. It won't break but best tool for the job etc.

It's generally accepted that cavers know more about this stuff than climbers - the rope being the means of transit rather than a means of not decking; the French cavers are also at the forefront of most of he developed techniques. Generally speaking the French riggers use fig. of 8's or 9's.

In reply to Wilbur:

It is useful for tying loops to make multiple anchor points - especially in abseil ropes - as it is easy to untie after loading. And its cool.

In reply to Wilbur:

you practising for it something in particular?

In reply to Wilbur:

thanks all

Nah Morgs, was reading Libby Peter's book last night and realised it was the only knot i didn't know in her book! so i started practising with a beer. i'm so rock n'roll!

In reply to brt:


Understanding the difference you highlight, I'd question whether impact forces are as significant in caving situations as they are in climbing?

I'd guess that cavers tend to use semi-static rope a lot more than climbers, what with all the rope ascending they do. That being the case, are there any subtleties in the use of dynamic rope which cavers might not typically have to deal with?

In reply to Wilbur:
err yeah....sounds like quite an evening ;o

In reply to brt:


thats a very good point. The other disadvantage to me using an AB is that i find them impossible to tie!!!

In reply to Martin W:

I'm not fulling understanding what you're asking re: the AB knot, but...

Impact forces shouldn't be significant in caving, but there is the all too easy possibility of higher than factor 1 falls and the subsequent forces. Relative to the question, I assume you're wondering what difference the knot type used might have? I'd suggest very little!

They do indeed. In relation (a very oblique one!) to the OP I'd guess none; though examples of what you mean may help.

I'm not trying to condemn the AB by the way. It's a good knot. Some of what I'm arguing is pretty subtle stuff and opinion based.

In reply to Wilbur:

In making equalised belays while conserving rope is the obvious use. Maybe that habit comes from caving?
jk

In reply to Wilbur: Rope access folk get very excited about the Alpine Butterfly for isolating rope damage and equalising anchors.
Hardly any Alpine guides use it, as an overhand is much easier to tie/teach/etc and just as good in most situations.

In reply to Wilbur:

The AB is really a caving knot, cavers will always take the simple option, the reason they use a complex knot like the AB is because it is possible to adjust the rope tension between knots on rigged sections better than with any other knot. On a caving trip in the Dales the rigging may involve 40 - 50 AB knots. Its other advantage is that you can tie it almost one handed with a bit of practice, which is handy in a tight spot.
However in climbing the overhand and figure 8 solve most problems and keep things simple.

In reply to Wilbur:

redundant knot

In reply to Dr Avid:

It's only got about 63% of the intergrity of the rope though...which, I suppose is better than the threads it's proberly hanging together by.

In reply to balti boy:

No, it is an extremely good knot for tying on in the middle of a rope without a harness (how and why it was first developed and used). It's also brilliant for setting up anchors for a static line, as many others have commented. I've used it many times for taking climbing shots using SRT, but I don't think I've ever used it for climbing, apart from very early days (mid-60s) in the Alps when we tied into a single rope.

In reply to balti boy:

PS. It's also a very beautiful knot, and a wonderful thing to tie.

In reply to Mike Hartley:

any advance on 61% to 72% ?

In reply to Wilbur: It`s my favourite Knot
Can you tie both ways so the loop lies in a different porientation to the rope. I was taught that it`s the only knot that allows a pull from 3 directions.
Also dead easy to untie.

In reply to J1234:

I was also taught that, if you use it simply to provide an extra anchor point, the line of force on the main rope goes straight through the centre of the knot. In effect, the extra loop is completely isolated, and the main rope is only very marginally weakened by the knot. I don't think any other such knot has that quality.

In reply to Gordon Stainforth:
And its easy to tie wearing mitts, using the hand wrap technique, so great for winter use.

In reply to J1234:

Yeah, I can't do that myself, but the knot has a near-magic quality, I think.

In reply to Wilbur: If I had to fall in love with a knot then I couldnt lve no other than a double fishermans, so neat and snug and stable

In reply to Fawksey:

The Alpine Butterfly is right up there with the Double Fisherman's, Fawksey.

In reply to Gordon Stainforth: symetry helps I think

however I hardly tie an alpine butterfly without tying a fig 9 at the same time

In reply to Gordon Stainforth:
As I sip my first Whisky of the year I shall think of an Alpine Butterfly, nay I may even tie a couple for complete bliss.

In reply to Fawksey:

The Figure of NIne I believe is the strongest of all knots. OK, it's got lots of merits, and it's very simple to tie, but it's extremely bulky. There's nothing remotely clever or interesting about it.

In reply to Fawksey:

PS. I should have said: when I'm setting up a static line for photography a Figure of 9 is what I use for my main anchor point, then subsidiary anchors are done with Butterfly Knots (so i suspect we're saying the same thing).

In reply to Wilbur:
Ive never used it, and Ive done lots of moving together and some bringing up two second at once...

I think a mate showed it me once but I just forgot and went back to the old figure 8 on the bight!

In reply to Wilbur: Really is very easy to tie, and is as cool as a knot could be, but still never use it.

In reply to Gordon Stainforth: at work when I set up two ropes for my working line and safety line a metre or so below the anchor points I always tie two opposed AB's and link them with a krab and it makes me feel even more satisfied with my rope work

In reply to Fawksey:

Sounds very neat.