Tying Two Ropes Together

Hey,

I do some fishing in addition to climbing, and have a knot related question:

In climbing I know most people use, and recommendations are for, a double fisherman's or flat overhand to join two ropes together for rappel and for creating cordelette. However, in fishing most everyone (and myself) uses a double uni knot to join two lines together (somewhat similar to a double fisherman's). I know the flat overhand is incredibly easy to tie and untie, and does not get hung up as much; but for those who use the double fisherman's - is there a reason this is chosen over a knot like the double uni? I find the double uni knot easier to tie correctly (perhaps because of much practice in fishing), and my search on the internet turned up nothing, not even the knot ever being tested for breaking strength with climbing rope/cordelette; only, of course, fishing line where it retains over 90% of original rated strength. Just curious, not planning on using it in climbing applications...

Thanks!

What context are you asking about? Purely for fishing? A double fisherman's will not be a good choice for thinner lines and braid since the knot will slip. Additionally, you cannot easily add wraps to the fisherman's to fix the slippage issue, so people just go for the double uni knot. A flat overhand doesn't sound great for fishing since it is likely to get caught on weeds (Even though this knot is less likely to get stuck in the wall while climbing). Additionally, thin line would also probably slip on a flat overhand; check out the surgeon's knot for a good alternative. 

In general, many of the climbing knots are good for thicker ropes and separate knots are better for thinner fishing lines. For climbing I cannot see any use for a uni knot because it will turn into a huge knot if you are using climbing rope.

Does anyone still use a double fishermans?  It seems to me the offset overhand is nearly universal---and for good reason.  Part of the point is that the strength of the knot isn't an issue, as it is for fishing line.  The critical things are stability (you don't want the knot untying itself), ease of riding over obstructions, and ease of untying.  I don't know how the double uni performs in rope or cord when it comes to stability and ease of untying (those collars might make it easier to loosen but also provide a mechanism for accidental untying), but it is bulkier than the double fishermans and the ends emerge perpendicular to the load strands rather than parallel to them, which seems to me to potentially create even more pulling resistance.

Double Uni

Double Fish

So as far as I can tell, it isn't as good as an option that has already been discarded by most people in favor of the offset overhand.

Ty Fluth wrote:

Hey,

I do some fishing in addition to climbing, and have a knot related question:

In climbing I know most people use, and recommendations are for, a double fisherman's or flat overhand to join two ropes together for rappel and for creating cordelette. However, in fishing most everyone (and myself) uses a double uni knot to join two lines together (somewhat similar to a double fisherman's). I know the flat overhand is incredibly easy to tie and untie, and does not get hung up as much; but for those who use the double fisherman's - is there a reason this is chosen over a knot like the double uni? I find the double uni knot easier to tie correctly (perhaps because of much practice in fishing), and my search on the internet turned up nothing, not even the knot ever being tested for breaking strength with climbing rope/cordelette; only, of course, fishing line where it retains over 90% of original rated strength. Just curious, not planning on using it in climbing applications...

Thanks!

I'm a lifelong fisherman and I, and most people I know stopped using the uni to uni years ago. It is the only fishing knot I have ever had fail or slip and I've caught bluefin to 200 lbs on a knot (not crimped). I switched to an R P knot and never looked back. I've always used a 3 turn surgeon's knot for tying fuoro to mono. I used to have to force myself to not accidentally tie a uni to uni instead of double fisherman's for climbing. Now I haven't used a uni in a long time and never mix them up. 

Oh also, I've seen all kinds of fishing knots get tested to their breaking strength and the only knot that I ever saw come out in the 90 percent range is a terminal knot called the SD jam. 

EDK all the way!

Keep it simple - flat overhand 

I use a "Square Fisherman's"

Tie a square knot and tie half double fisherman stopper on each side with 1" tails.  This is easier to untie than a double fisherman's after being weighted. isn't as bulky as a figure 8 / Flemish bend.

I know some like the EDK. I worked with Tom Moyer back in the day on testing knots. The figure 8 EDK is very bad as it can capsize and keep walking of the end of the rope. The EDK can capsize, but will stop after one roll. I personally don't like EDK because it is an overhand knot which is 50% loss and then of all things it's being loaded improperly and wanting to force it apart! If I climb with someone who prefers it, I kindly ask to let me go first on something else, and they can on follow on the EDK. I recently had several ropes set up as fixed lines for a week, while instructing a course and at the end of the week it was easy to untie the ropes.

For joining two ropes together for rap? Can’t beat the EDK.
not that good for joining ropes together for a double or triple single strand fixxed line 

honestly, would rather do multiple single rope rappells, even on large routes due to less rope tangles and the weight of 2 ropes.  70m ropes have really changed that dynamic.   If I have to, I’ll use a standard figure 8 follow through with 1-2’ tails.  It’s simple, everyone understands the knot, it’s easy to untie and doesn’t hang up as often as fisherman’s or others.   Tails help it roll though sections and my experience is the flat knot helps leverage and is less prone to catching.   Hard pass on EDK! 

Surprising how complex people are making this topic... consider these:

1. Simplicity. How efficiently can you tie your knot/bend? Is it a pain the ASS for your partner to try and double check your bullshit knot that nobody has heard of? If so, you should reconsider.

2. Strength. Understand how knots/bends effect the strength of your rope. Once you understand that, your concerns for decrease in strength should disappear. If you're still worried about putting 800+lb of force on your flat overhand, you're being a little paranoid. If you're worried about the flat overhand rolling 9 times off the end of your two feet of tail, you're being a little paranoid. Just tie it tight

3. Functionality. Is your knot/bend low profile? Will it roll over patina, horns, cracks etc without getting caught up? Does it have any loops that can hook onto said features? If it doesn't minimize risk of getting stuck while pulling, you should reconsider.

4. Should you always default to double rope raps just because you have two ropes? Probably not. Single rope raps reduce tons of risks and pains involved with rapping. Understand and recognize what your specific terrain is calling for. It usually tells you!:)

Take all of this with a grain of salt. There is not one knot or bend that works in every scenario. Sometimes you may have to change it up depending on what the terrain throws at you.

But there is one option that works 99% of the time and fits these criteria. Don't make it more complex than it needs to be. My 2¢.

Matt Heinen wrote:

Surprising how complex people are making this topic... consider these:

1. Simplicity. How efficiently can you tie your knot/bend? Is it a pain the ASS for your partner to try and double check your bullshit knot that nobody has heard of? If so, you should reconsider.

2. Strength. Understand how knots/bends effect the strength of your rope. Once you understand that, your concerns for decrease in strength should disappear. If you're still worried about putting 800+lb of force on your flat overhand, you're being a little paranoid. If you're worried about the flat overhand rolling 9 times off the end of your two feet of tail, you're being a little paranoid. Just tie it tight

3. Functionality. Is your knot/bend low profile? Will it roll over patina, horns, cracks etc without getting caught up? Does it have any loops that can hook onto said features? If it doesn't minimize risk of getting stuck while pulling, you should reconsider.

Take all of this with a grain of salt. There is not one knot or bend that works in every scenario. Sometimes you may have to change it up depending on what the terrain throws at you.

But there is one option that works 99% of the time and fits these criteria. Don't make it more complex than it needs to be. My 2¢.

In my 38 + years of climbing I have never had to abandon a rope due to not being able to retrieve it! (came close once and was about to prussik back up the 2 lines)

As someone who runs programs and teaches other instructors. Best to use easy to tie, recognize and accepted by others

be able and comfortable with several options, just in case you are with someone and need to compromise. Also important in various conditions (wet, icy, muddy, multiple double rope rappels and emergency situations when stress can be a factor!)

Keep it Simple

A new rope(s) will still cost less than my ER copay! and be less painful, and I get a new rope!

Again just my $0.02, your experience may differ. SAFETY FIRST!

jc5462 wrote:

In my 38 + years of climbing I have never had to abandon a rope due to not being able to retrieve it! (came close once and was about to prussik back up the 2 lines)

As someone who runs programs and teaches other instructors. Best to use easy to tie, recognize and accepted by others

be able and comfortable with several options, just in case you are with someone and need to compromise. Also important in various conditions (wet, icy, muddy, multiple double rope rappels and emergency situations when stress can be a factor!)

Keep it Simple

A new rope(s) will still cost less than my ER copay! and be less painful, and I get a new rope!

Again just my $0.02, your experience may differ. SAFETY FIRST!

Love it!

Tying two ropes together is kinda broad. Lots of use cases other than double rope raps. For instance, Ryan Jenks repeated Dano's big rope jump a few moths ago, with multiple ropes tied together. I'll EDK all day long for raps, but no way am I using it on a rope jump (as much to do with tidiness of the knot as rolling). F

Pete S wrote:

honestly, would rather do multiple single rope rappells, even on large routes due to less rope tangles and the weight of 2 ropes.  70m ropes have really changed that dynamic.   If I have to, I’ll use a standard figure 8 follow through with 1-2’ tails.  It’s simple, everyone understands the knot, it’s easy to untie and doesn’t hang up as often as fisherman’s or others.   Tails help it roll though sections and my experience is the flat knot helps leverage and is less prone to catching.   Hard pass on EDK! 

Are you describing a flat figure 8 bend, or a flemish bend? 

jc5462 wrote:

I use a "Square Fisherman's"

Tie a square knot and tie half double fisherman stopper on each side with 1" tails.  This is easier to untie than a double fisherman's after being weighted. isn't as bulky as a figure 8 / Flemish bend.

I know some like the EDK. I worked with Tom Moyer back in the day on testing knots. The figure 8 EDK is very bad as it can capsize and keep walking of the end of the rope. The EDK can capsize, but will stop after one roll. I personally don't like EDK because it is an overhand knot which is 50% loss and then of all things it's being loaded improperly and wanting to force it apart! If I climb with someone who prefers it, I kindly ask to let me go first on something else, and they can on follow on the EDK. I recently had several ropes set up as fixed lines for a week, while instructing a course and at the end of the week it was easy to untie the ropes.

That is the case for everything knot, including the reef knot. Strength retention is not a relevant consideration in knots for climbing. If the knot is secure and stable enough that it breaks, then it's fine. Use rope/cord that is strong enough in the first place.

Try this recently published information on Petzl's website: Knots for joining rappel ropes

Water knot

It really depends on what I'm doing as to the knot I tie. Fly fishing I usually tie a double surgeon knot for tying a tippet onto the main line. In climbing it depends on the use- cordalettes or other things that I 'm looking for a fixed knot, I'm usually tying a Double or Triple Fisherman. For things that I'm looking to untie easily afterwards (rappels or when doing tree work) I typically use a Zeppelin Bend. 

j Roc wrote:

Try this recently published information on Petzl's website: Knots for joining rappel ropes

locally people have been using the EDK with an additional overhand of one strand to prevent the rolling of the EDK.  Similar to the 3rd option in petzl's document but with less bulk.

Photo above is not an EDK. It's a water knot with an extra overhand on one stand.

SICgrips wrote:

Photo above is not an EDK. It's a water knot with an extra overhand on one stand.

Wrong.  It is just very well dressed EDK with an overhand.  

EDK

EDK with overhand to prevent rollling.

Edit:  FYE, a water knot.

Tim Wheatley wrote:

Water knot

That sounds like a recipe for a partner rapping off one standing end + one tail end, since the the EDK is so, so, so, much more common.