How would you join SRT rope ??

[Paul_L]

Been playing with an AB. If you repeatedly unload it and then load it again, albeit only with hand forces, it seems to work loose very easily. With a bit of twist in the rope a hitch (?) can come off the knot and flip over the loop, effectively undoing the whole thing. Or, with a bit of wiggling, the whole loop looks like it wants to pull through the knot leaving nothing but the DF. Is this anything to worry about?

It is possible for this knot to fail if it is loaded and unloaded if it hasn't been tightened properly, which it will be as soon as it is passed by the rigger.
In this use it wouldn't be a problem if it did fail as the double fishermans in the loop would still be sufficient but a bugger to undo!

 

[Dep]

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Oh dear...... Dep I hope I didn't upset you by posting that link.
...
Having read the rest of this thread and looking at some very interesting pictures, I'm willing to accept that there are as many ways of joining a rope as there are ways to set up a pub.

Not at all - I was just being flippant.
My point of course was what you have also said - that there are lots of ways to do it - all of them work, none have serious drawbacks.

 

[Downer]

Been playing with an AB. If you repeatedly unload it and then load it again, albeit only with hand forces, it seems to work loose very easily. With a bit of twist in the rope a hitch (?) can come off the knot and flip over the loop, effectively undoing the whole thing. Or, with a bit of wiggling, the whole loop looks like it wants to pull through the knot leaving nothing but the DF. Is this anything to worry about?

It is possible for this knot to fail if it is loaded and unloaded if it hasn't been tightened properly, which it will be as soon as it is passed by the rigger.
In this use it wouldn't be a problem if it did fail as the double fishermans in the loop would still be sufficient but a bugger to undo!

Assuming the rigger doesn't return up the rope at that point. What's the thinking on this - is fully loading every knot normal rigging practice?

 

[Geoff R]

Been playing with an AB. If you repeatedly unload it and then load it again, albeit only with hand forces, it seems to work loose very easily. With a bit of twist in the rope a hitch (?) can come off the knot and flip over the loop, effectively undoing the whole thing. Or, with a bit of wiggling, the whole loop looks like it wants to pull through the knot leaving nothing but the DF. Is this anything to worry about?

It is possible for this knot to fail if it is loaded and unloaded if it hasn't been tightened properly, which it will be as soon as it is passed by the rigger.
In this use it wouldn't be a problem if it did fail as the double fishermans in the loop would still be sufficient but a bugger to undo!

Assuming the rigger doesn't return up the rope at that point. What's the thinking on this - is fully loading every knot normal rigging practice?

Nope - traverse line knots prob usually dont get "fully" loaded ....

 

[Downer]

Been playing with an AB. If you repeatedly unload it and then load it again, albeit only with hand forces, it seems to work loose very easily. With a bit of twist in the rope a hitch (?) can come off the knot and flip over the loop, effectively undoing the whole thing. Or, with a bit of wiggling, the whole loop looks like it wants to pull through the knot leaving nothing but the DF. Is this anything to worry about?

It is possible for this knot to fail if it is loaded and unloaded if it hasn't been tightened properly, which it will be as soon as it is passed by the rigger.
In this use it wouldn't be a problem if it did fail as the double fishermans in the loop would still be sufficient but a bugger to undo!

Assuming the rigger doesn't return up the rope at that point. What's the thinking on this - is fully loading every knot normal rigging practice?

Nope - traverse line knots prob usually dont get "fully" loaded ....

And the loop is attached so the butterfly can't undo completely though it can degenerate into two separate hitches.

Anyway, let's be more specific. When knotting or rebelaying is it normally reagarded as essential to load the knot with body weight to tighten it or is this just something we're inventing here to deal with the fact that an AB undoes rather easily?

 

[Geoff R]

Been playing with an AB. If you repeatedly unload it and then load it again, albeit only with hand forces, it seems to work loose very easily. With a bit of twist in the rope a hitch (?) can come off the knot and flip over the loop, effectively undoing the whole thing. Or, with a bit of wiggling, the whole loop looks like it wants to pull through the knot leaving nothing but the DF. Is this anything to worry about?

It is possible for this knot to fail if it is loaded and unloaded if it hasn't been tightened properly, which it will be as soon as it is passed by the rigger.
In this use it wouldn't be a problem if it did fail as the double fishermans in the loop would still be sufficient but a bugger to undo!

Assuming the rigger doesn't return up the rope at that point. What's the thinking on this - is fully loading every knot normal rigging practice?

Nope - traverse line knots prob usually dont get "fully" loaded ....

And the loop is attached so the butterfly can't undo completely though it can degenerate into two separate hitches.

Downer, just a thought, when you mention two separate hitches of your butterfly coming undone, are you referring to a Cavers Butterfly or to the similar looking Alpine Butterfly (which has very different attributes).

 

[Downer]

Downer, just a thought, when you mention two separate hitches of your butterfly coming undone, are you referring to a Cavers Butterfly or to the similar looking Alpine Butterfly (which has very different attributes).

Probably best to ignore my use of the word hitch. I did put a ? after it.

I meant the proper Alpine Butterfly in the context of a knot joining two ropes as suggested by Cave Troll, and the Caver's Butterfly in the context of rigging a traverse line as mentioned by you.

The Caver's is really just two overhands threaded with the opposide ends of a loop, only it's dressed so that one overhand also wraps the other. Not surprisingly it can deform into two separate threaded overhands. They don't come undone, they just separate.

As far as I can tell, the Alpine doesn't unravel even if you try to make it as the two overhands are themselves chained. However if the loop is not attached to anything, another loop can escape from a very loose knot and pass over the intended loop letting the whole thing fall apart.

 

[Geoff R]

Ha that makes sense.  Personally Ive never found any problem with Alpine Butterfly's (except that it is slightly more difficult to adjust)  and indeed I choose to always use an Alpine Butterfly.

Im guessing that the only way an Alpine Butterfly could come undone is by having a very short loop AND with nothing in it such as a krab;  In my experiance I dont like the "round the hand" tie method for this knot due to its difficulty to make any reasonably decent loop length.

just an observation 

 

[LarryFatcat]

According to PETZL (http://en.petzl.com/petzl/SportConseils?Conseil=43&Activite=26)

use a fig 8 derivation.

I like this, tie the double fig 8 then rethread joined on rope, looks and feels right.

 

[docfunk]

According to PETZL (http://en.petzl.com/petzl/SportConseils?Conseil=43&Activite=26)

use a fig 8 derivation.

I like this, tie the double fig 8 then rethread joined on rope, looks and feels right.

agreed.

 

[LarryFatcat]

Double fishermen's are pigs to undo. hence why some people choose to put a reef knot in the middle. this however, makes the whole "knot" assembly longer and a bit harder to pass.
The above "alpine butterfly with a double fish in the loop" is secure, easier to undo and includes a safety loop to clip in to .

Why even consider something that could come partially undone when there are a number of perfectly easy and safe alternatives??

 

[Cantclimbtom]

Double fishermen's are pigs to undo. hence why some people choose to put a reef knot in the middle. this however, makes the whole "knot" assembly longer and a bit harder to pass.
The above "alpine butterfly with a double fish in the loop" is secure, easier to undo and includes a safety loop to clip in to .

Thanks! In future, this is now going to be my first choice

 

[Fulk]

Hi Geogg R, is this what you mean by:

'Starting this off, how about using one half of a double fisherman's as the stopper knot, then completing this to join the new rope and then isolating the double fisherman's using an Alpine Butterfly?'

 

[topcat]

I'm with the threaded fig8. Given that you will be hanging about when you do this I want simple . The fig 8 loop is already there in the end of the rope: more than half the job is already done for you, and even if you have a total brain fart you have the fig 8 to simply follow on the re- thread. Your safety loop is ready made . And won't be coming undone.

And it looks pretty if the two ropes are different colours. This will shine a little joy on a crap situation. 🤗

 

[mikem]

This thread is almost 15 years old...

 

[topcat]

Was..

 

[mikem]

Indeed, but we're now discussing exactly the same thing on two different threads!

 

[MarkS]

Thread locked due to duplicate.