Knot for differing diameter ropes?

Hey everbody!, was just thinking about this and thought I'd throw it out there (being bored today and all). I use a 8mil static for a tag line, as well as rapping with my lead line. Usually I just go double fishermans to join them.....is there a better way to connect differing diameter ropes? Is the "Euro-death knot" a bad idea for differing diameters?

Thanks!

A double sheepbend works great for tying ropes of different diameters together. It is strong, low profile, and very easy to untie after being loaded. I use this knot all the time

What do people think of using a butterfly knot to connect ropes of two differing diameters?

I normally use the euro death knot unless the difference in diameters looks scary, then I use a locking biner.

T, maple or santaquin on Saturday?

"then I use a locking biner."

Lost me there JG...a locker? for what? please enlighten.

Would love to...but I've got plans already for this weekend. Is Sanatquin in?

Do you lead 5's?

In fishing the best knot for adjoining two pieces of line of largely different diameters is a surgeon's knot. I have never heard or seen it used in climbing but what is the consensus here? Is this knot a big no-no?

flymartonline.com/article21…

Yo Jeff, that knot is the bomb for big browns...may be a bit bulky for a few ropes though. Gonna have to try it tonight and see just how big it is

The surgeons knot looks an awful lot like a figure eight.
I'd stick with the double fishermans knot.
I've used it to combine an 11mm and 8mm cord and it's never failed.

Tea wrote: Lost me there JG...a locker? for what? please enlighten.

I don't tie them together. I put a figure eight on a bight on the ends of both ropes and lock them together with a small locking carabiner, or two carabiners.

Tea - What I'm doing with a double-strand rap -- flat overhand with the larger strand through the anchor; take the smaller strand (tag line) and make another single-strand overhand to prevent the main 2-strand knot from rolling out. Make sure the main knot is well dressed & snug (And, you've got long tails).

Skinny static w/ fatter dynamic

Here's the site Avery linked showing the test ratings of the knots:
EDK Knot Tests

Tom Hanson wrote:The surgeons knot looks an awful lot like a figure eight.

It may appear from that drawing but it is far from a figure eight...Tea let me know what you think...I have always thought about incorporating more fishing knots into climbing but never have. Maybe its kosher maybe not...

Thanks guys...guess I should have just searched it. Cheers!

John J. Glime wrote:I don't tie them together. I put a figure eight on a bight on the ends of both ropes and lock them together with a small locking carabiner, or two carabiners.

Better yet just tie the bights together (by rethreading one end similar to how you tie into the rope). Saves wear and tear on the biners.

I've also used a square knot backing up the ends with double fishermans knots. This is a lot easier to untie than a double fishermans itself. The square knot by itself is not safe, but with the tails in double fishermans it's bomber.

George - I use the same technique (square knot) and I love it because I don't have to spend 20 minutes getting them apart. Think I learned that from one of Craig Luebben's book's.

George Bell wrote: Better yet just tie the bights together (by rethreading one end similar to how you tie into the rope). Saves wear and tear on the biners.

Flemish bend?

answers.com/topic/flemish-bend

Seems like a pretty good way to go.

I use the EDK with a 6mm tied to a 9.4mm all the time (not that anyone should). Tightly tensioned, with another overhand snugged against the first one, usually. Even TR'd a few longer pitches this way. Never seen an issue with it. Pretty easy to untie.

YMMV...

Some relevant discussion here

Brian in SLC wrote:Flemish bend? answers.com/topic/flemish-bend Seems like a pretty good way to go.

I was thinking more of this: when completed, the knot looks EXACTLY like two bights joined by a biner except that there is no biner (the bights being jouned to themselves). So there are two separate figure 8 knots, one on each strand.

I'm not sure how a flemish bend works on different diameter ropes ... never tried it myself.

George Bell wrote: I was thinking more of this: when completed, the knot looks EXACTLY like two bights joined by a biner except that there is no biner (the bights being jouned to themselves). So there are two separate figure 8 knots, one on each strand. I'm not sure how a flemish bend works on different diameter ropes ... never tried it myself.

Give 'er a look see, George. Nice is if you ever have to pass a knot, you can start with a figure eight on a bite and rethread the other rope through that. Makes for nice transfer and something bomber to clip into.

Most definately the "Euro Death knot" . Make sure your tails are at least 6 or 7 inches long. When using a smaller diameter "Tag" line simply tie the knot then use the smaller diameter tail to tie a half fishermans around the larger diameter tail strand. This is usually very low profile and all stands upward away from the rock when pulled.

I have a problem with any connector knot that is not adequate by itself, even if it is backed up by fisherman's knots. When the backup knots are not loaded they have a tendency to loosen and unravel by themselves. In the extreme this could leave you dependent on the connector knot. Give me a connector knot that won't come undone, and even if it is a hassle to untie I'll be happy.

I think the test results show the flat overhand is adequate for a rap when tied properly.

Along the lines of a backup knot, how many tie that "safety knot" above their figure 8 retrace? Does the use of this backup safety knot indicate also that the figure 8 retrace is inadequate to hold the force of a leader fall? I think knot.