By Declan Cunningham
In a new series of mini articles and videos, Outsider teaches you basic skills that will come in handy for life in the outdoors.
What it is and what it’s used for:
A French prusik is one of the more common friction knots used by climbers as a safety back-up while abseiling. The idea is that if you should you become incapacitated while abseiling the prusik will lock and your descent will be stopped.
What you’ll need:
You will need a loop of accessory cord to tie the knot. Ideally the accessory cord should be 6-7mm in diameter which is about 60-70% of the thickness of the rope it is meant to grip. The loop is generally tied off using a double fisherman’s knot and is about 45cm in looped length, ie you’ll need about 90cm of cord to tie the loop.
Prusik Knot
How to tie it and how it’s used:
Keeping the double fisherman’s knot out of the way, make wraps of cord around your rope. The knot can be tied on single or double ropes but obviously if two strands are involved the prusik must be tied around both. The greater the number of wraps used the greater the friction achieved. Some people only use three wraps but I would recommend four or five. When your wraps are complete bring the two ends of the loop together and attach them to a karabiner. The karabiner then attaches to the leg loop of your harness and is locked off.
Advantages, disadvantages, pitfalls:
The great thing about the French prusik is that it’s very easy and quick to tie and it’s also very easy to release after it’s been loaded. This is why it’s so popular as a backup for abseiling. The trouble is that it can also be released under load which means that it’s potentially dangerous. Perfect how to tie it and the number of wraps that work best for you considering the rope that you climb with and it won’t let you down.
Watch the video!
[...] Outsider Magazine – How to: tie a French prusik 12 Mar 2010. A French prusik is one of the more common friction knots used by climbers as a. You will need a loop of accessory cord to tie the knot. Outsider Magazine – How to: tie a French prusik [...]