The double figure-8 fishermans knot is the best knot to tie two ropes together for rappelling.
Rappelling is Dangerous
Rappelling is one of the most dangerous aspects of climbing. More accidents occur rappelling than any other climbing activity except lead climbing. When you’re rappelling off a cliff, you’re relying solely on your equipment—on your rope, on your rappel device, on your harness, and on the anchors that your rope is threaded through. Besides having perfect bombproof anchors, you need to tie your ropes together with a strong knot that will support your weight while rappelling and won’t come untied.4 Best Knots for Rappel Ropes
The following four best knots are the best ones for tying your rappel ropes together:- Double Figure-8 Fisherman’s Knot This knot, the usual way to tie rappel ropes together, is the strongest of the bunch and, if properly tied, will not come undone. It’s also easy to visually check to make sure it is properly tied. It’s usually not difficult to untie after being weighted. This is the best knot to tie ropes of unequal diameters, that is a thin rope and thick rope, together. The knot’s biggest disadvantage is its bulk, so the chances that it might jam in a crack while you’re pulling the rappel ropes are increased.
- Square Fisherman’s Knot A lot of climbers like this knot because it’s easy to tie and the easiest of these four knots to untie. It’s basically just a square knot backed up with double fisherman’s knots on either side. If you use this knot, always use the backup knots or risk it coming untied. A square knot alone is never a good knot for rappelling or any other climbing purpose.
- Double Overhand Knot This knot, sometimes called the “European Death Knot,” has gained popularity and is often used to tie ropes together. It is the fastest and easiest of these four knots to tie and has the least bulk, which makes it less likely to snag and stick your rope. Do not use this knot with ropes of varying diameters, since at least one fatal accident has occurred from it coming untied. Alternatively you can tie a double figure-8 knot instead of the overhand knot, although testing at Black Diamond’s lab in Salt Lake City indicates that the double overhand is stronger than the double figure-8.
- Double Fisherman’s Knot This is the traditional knot to tie two ropes together but has generally fallen out of favor for the above knots. It can be difficult to check visually and is often difficult to untie after being weighted, particularly if the ropes are wet. This knot is best used for tying thin pieces of accessory cord like Spectra together for anchors or slinging nuts like Hexentrics.