The Prusik knot is a friction knot or hitch that is tied around a climbing rope with a thin length of cord. When a climber’s weight is loaded onto the knot, it tightens and cinches onto the rope. Prusik knots, commonly used in pairs or with another friction knot like a Klemheist knot or Bachmann knot, allows the climber to ascend a fixed rope by sliding the knot up the rope.
When to Use a Prusik Knot
Prusik knots are primarily used by climbers in emergency situations when it is necessary to ascend a fixed rope. These situations include lending aid to an injured climber above, ascending up an overhanging face after falling, or extricating oneself after falling into a glacial crevasse. Every climber needs to know how to tie a Prusik knot. With practice it can be easily tied with one hand, a good skill for emergencies.
Make 2 Loops of Cord
To tie a Prusik knot you need what climbers call “Prusik slings,” which are two lengths of thin cord (preferably 5mm or 6mm in diameter). The thinner the cord is in relation to the thickness of the climbing rope, the greater the ability of the knot to cinch onto the rope. It’s best to make the Prusik slings about two feet long, although some climbers like having one of the slings longer. Buy a five-foot length of thin nylon cord that is specifically made for climbing. Avoid buying spectra cord since it can melt if the knot slips. Tie the ends together with a double-fisherman’s knot, forming a closed loop.
First Step to Tie a Prusik Knot
The first step to tie a Prusik knot is to take the loop of cord and place it behind the main climbing rope.