Usage
The Klemheist is a directional friction hitch primarily used in climbing and rescue operations for ascending or descending a rope. Unlike bi-directional hitches like the Prusik, the Klemheist grips firmly in one direction while sliding easily in the opposite direction, making it ideal for both nylon and static ropes. One of its key advantages is the ability to tie it using either cord or webbing, offering flexibility based on the environment and available materials. Compared to the Prusik, the Klemheist generally slides upward with greater ease, making it a preferred choice for upward mobility during climbing or rescue.
Warning
Verify tying technique with a skilled instructor where knot failure could cause property damage, injury, or death.
History
The Klemheist derives its name from the Dutch word klem, meaning 'clamp.' It originated as a variation of the Prusik knot and belongs to the family of friction hitches. The knot can be traced back to early rappelling, abseiling, and self-rescue techniques, where it provided a reliable, one-way gripping function.
Also known as
- French Machard Knot
- Kleimheist (common misspelling)
ABOK
Structure
The Klemheist is tied using a Prusik loop, typically made from a short section of rope joined by a Double Fisherman's Knot. Alternatively, pre-made loops can be purchased from climbing shops. The loop is wrapped several times around the main rope, with the tail passed through the bottom loop to secure the hitch. This arrangement creates a strong grip in one direction, making the knot particularly effective for use in load-bearing applications, such as ascending or hauling gear.
Strength/Reliability
As a general rule, the cord used for friction hitches like the Klemheist should have a diameter that is no more than 70% of the main climbing rope’s diameter. However, this guideline may vary based on the cord’s stiffness and material. It's important to consider the potential heat generated from friction, which can degrade the cord over time, especially during extended use or under heavy loads.
