Knots for joining two ropes for life support

[CanadianStan]

Double fishermans is usually the go to knot for joining life support ropes of similar diameter

That’s what I use... makes me feel good.

 

[evo]

That’s what I use... makes me feel good.

It's certainly bullet proof, and has the highest break strength!

 

[Chaplain242]

One other knot which I rarely use but has its place is a EDK (overhand backed with another overhand) but requires both ropes to be supple. Used where the join must pass over a edge or scaffold/union that would jam something like a fishermans etc. But not encouraged for general use and if ropes too stiff is a dangerous knot.

 

[Ronhayden]

What about a Carrick bend? I feel as though there’s more rope to rope contact it would make me feel better but what’s people’s opinion on it ?

 

[RopeShield]

Lapp knot/Santa with overhand back up is my go to, what I use to use for making prusik loop and still use for joining rig lines
If you use two ropes best is metal link between the two

 

[evo]

What about a Carrick bend? I feel as though there’s more rope to rope contact it would make me feel better but what’s people’s opinion on it ?

you can use all kinds of knots... BUT... whatever is used needs to be easily identifiable to make sure it's tied right.

 

[Cereal_Killer]

What about an Alpine butterfly?

It works great for joining two lines. It is what I use in most situations where that is needed.

The EDK also works very well with most of our double braid climbing lines.

I love the AB when tied in loop form, it's my first choice in most applications and the only knot I use for a canopy anchor (with a short tail), but not for joining two lines! I've [thankfully] caught someone I would consider an expert make this mistake more than once checking each other's knots before a climb... Also worth mentioning, the imposter link posted below looks and feels solid, had I not been such a fan of the AB I probably wouldn't have caught it. It took me a sec; "looks good, looks good, wait what's going on here, somethings not right. DAMN DUDE YOU ALMOST DIED!"

Butterfly Bend

EDK is easier to identify when improperly tied but much harder to untie after loading.

 

[SomethingWitty]

That is quite an inspiration to study and practice.

 

[DSMc]

... caught someone I would consider an expert make this mistake more than once...

Surely not the same guy! How were they tying it? I have never seen an AB bend tied wrong when tied using the twist method.

Yeah, the EDK is safe but not the best if heavy loads are anticipated.

 

[RyTheTreeGuy]

I have never had to join ropes for tree work, but have done it for technical rope training. The figure 8 is the champion of that field for most of the work I have done (we also use Alpine butterflies, bowline, etc) but we do a figure 8 bend. Instead of joining the loops together like the OP showed we join the ropes. Figure 8 stopper on the end of 1 line, then retrace (or follow through) the figure 8 with the second line. Makes for a shorter termination which is easier to pass with your repel device, add your choice of safery if necessary, but its pretty bomb proof if TDS

 

[TreeCo]

For life support:

Retraced figure 8
Double sheet bend

 

[Treetopflyer]

For joining two climbing lines (the original question), I like the Double Overhand/Fisherman's knot. I've never had an issue separating ropes reasonably quickly after climbing use, there's a method and skill to it just like everything in tree climbing. I like the neatness, compactness and tail orientation compared to say the Zeppelin. For rigging? Ugh, I really dislike tying ropes together for rigging, no matter what knot you use, there's a good chance you'll weld two ropes together if you're rigging anything with above average weight. Been there. For light rigging whatever you like the most, double overhand fisherman's no.
-AJ

The zepplin is not difficult to untie even with some
Large force applied.To tie and untie.. I love that knot

 

[Steve Connally]

Tracer 8 is what everyone is talking about. Industry standard for tech rescue but certainly will not pass through a repel device or anything other than a knot passing pulley.

 

[RyTheTreeGuy]

Tracer 8 is what everyone is talking about. Industry standard for tech rescue but certainly will not pass through a repel device or anything other than a knot passing pulley.

Was not suggesting it would pass through a repel device or anything else. Simply the skill/task of passing a knot while on rope. Eg. Repel down to end of rope, attatch second line with bend of choice (figure 8), prussik off (or mechanical), remove rappel device, re-attach rappel device below the bend then carry on....

 

[Steve Connally]

Was not suggesting it would pass through a repel device or anything else. Simply the skill/task of passing a knot while on rope. Eg. Repel down to end of rope, attatch second line with bend of choice (figure 8), prussik off (or mechanical), remove rappel device, re-attach rappel device below the bend then carry on....

Gotcha. Used a lot in haul and lowering systems too.

 

[rico]

Zeppelin or a bowline for me.

 

[Cliff_Towle]

How about a double fishermans with each end connected to an oval biner? Would be easy to untie.

 

[Mowerr]

How about a double fishermans with each end connected to an oval biner? Would be easy to untie.

Yes its easy to separate rope via the biners bit the knots will still see the same loads. But for life support loads, you could untie the knots fairly easy but if rigging - god bless the guy who has to untie those knots.
But when heavy loads cinch knots like these up soo tight ill use a saw wrench to help open them up... Still its no fun

 

[RBJtree]

A pair of scafold knots on an oval biner would do well I think. Removal would be fairly easy if the profile of the biner allows it to be removed, then the knots can just be pulled apart.
I've used a bowline with a pair of half hitches on each side, but I have since learned that is not the safest due to the possibility of the half hitches and bowline working there way out after repeated load cycles.

 

[Phil]

I have never had to join ropes for tree work, but have done it for technical rope training. The figure 8 is the champion of that field for most of the work I have done (we also use Alpine butterflies, bowline, etc) but we do a figure 8 bend. Instead of joining the loops together like the OP showed we join the ropes. Figure 8 stopper on the end of 1 line, then retrace (or follow through) the figure 8 with the second line. Makes for a shorter termination which is easier to pass with your repel device, add your choice of safery if necessary, but its pretty bomb proof if TDS

Came across this article. Does this look like what you're referring to with the retraced 8 but without the bite?

Euro-Death Knot (Flat Figure-8) Mysteriously Fails

Many climbers use and love the European Death Knot (EDK), believing that it is the best knot for tying two ropes together. The knot can, however, flip and roll down the rope, coming completely untied.

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