Monday, April 4, 2022

The Double-Fisherman's Knot

Arguably, the most difficult knot to teach is the double-fisherman's knot. It is normal for our guides to spend a significant amount of time with students on this particular knot. And even with a lot of time spent focusing on it, some still don't come away with a master's level knowledge of it.

If you have this knot completely wired, then congratulations. If you don't, then this blogpost is just for you...!

The Double-Fisherman's Knot

The double-fisherman's knot is a knot that may be used to join two ropes together. The ropes may be of similar or dissimilar diameters. It is a very secure knot. Indeed, it is so secure, that it is often recommended for cords that will be permanently tied together such as prussik loops.

The biggest problem with the double-fisherman's is that it is very difficult to untie once it has been loaded. As a result, it is not recommended for quick situations where you want to tie two ropes together, such as in rappels.

The Canadian Guide, Mike Barter has put together the following video on how to tie a double-fisherman's knot:


As a side-note, while we call this the double-fisherman's knot, that's not exactly right. It is a "bend," instead of a knot. In knot parlance, a bend is a knot that joins two cords or two ropes together.

--Jason D. Martin


Unknown said...

Jason, It seems a lot of guides and experienced climbers use EDK's for both tying rappel ropes together as well as cordallettes. Besides tying prussics, what else would you use a double fisherman's for? Also, what do you consider a safe tail length when using, say, 7 - 9 mm cord? -

Jason Martin said...

If there is a large diameter difference between ropes or cords, it's better to use a double-fisherman's knot.

I would say that you should have about two to three inches on smaller cords on the ends...


Doug Sanders said...

A simple method is to tie the 1st half, flip cords 180 degrees and tie 2nd half using the identical (1st half) motions. Easier for novice, a bit disdainful to experienced.