Self-locking device

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Self-locking devices are devices intended to arrest the fall of solo climbers who climb without partners. This device is used for back rope solo climbing for "ground-up climbing" or "top rope self belaying". To date, several types of such self-locking devices have evolved.

Contents

Types

Prusik sling

The earliest type of self belay device used was the ubiquitous prusik knotted sling used by climbers. The method requires the soloer to feed out an estimated length of belay rope so that he can reach his next stance and repeat the process as the rope is difficult to feed through the prusik knot while climbing.

Gibbs-style type 1 ascender

A Gibbs-style ascender. Gibbs Ascender.jpg
A Gibbs-style ascender.

The next level of device development improved on the locking limitations of the prusik sling by utilizing a cam that is activated by the climber's body moving down to rotate the simple grab cam inside a rigid frame. The climber's harness is directly attached to the cam and the frame encapsulates the rope.

Early versions of the cam systems used a Gibbs-style type 1 ascender placed in an inverted position attached to a soloer's sit harness opposite to the manufacturer's intended use. The combination of a climber's body position in a fall and friction between the ascender frame and the rope provides the activating leverage for the cam to grab the rope. Fall forces generated using this device and the cam profile can be enough to damage a rope due to the high clamp loads induced by the cam lever arm. The main drawback to this system is that it is like the prussik knot system where the soloer also has to feed out an estimate amount of rope in order to reach a stance point.

Floating cam ascender

The Wren Industries 'Soloist'. Wren Industries Soloist.jpg
The Wren Industries 'Soloist'.

A big improvement over the Gibbs-style type 1 ascender was the design of the Wren Industries "Soloist" – the device incorporates a floating cam that is activated by the relative position of the rope to the device frame, with the frame secured between a user's sit harness and a chest harness. The Soloist allows the rope to feed without the need for the soloer to manually feed out between stances – so it allows a 'true' hands-free climb.

Knowledge of the correct device position relative to the rope anchor is critical for the correct operation of the cam devices in a fall as they are mono directional in operation, and the soloer must be aware that he needs to put in a runner as soon as he sets off above the belay point on a multi-pitch climb, otherwise he can slide to the bottom of the rope in the event of a fall. The Soloist cam profile design allows the belay rope to be "grasped" rather than crushed as in the early cam devices.

Inertial drum brake ascender

The Wren Industries 'Silent Partner'. Wren Industries Silent Partner.jpg
The Wren Industries 'Silent Partner'.

To overcome these limitations, the Wren Industries 'Silent Partner' device was developed. This system has four mechanical moving parts inside a frame that is attached to a climber's sit harness and is basically an inertial drum brake with the belay rope connected to the device by tying a clove hitch around the device's drum. The Silent Partner is unique in the sense that it operates in both directions of drum rotation so it can be attached to a climber's sit harness in either position, eliminating the danger of stepping off a multi-pitch anchor point before the first runner can be placed.

Illustration of a clove hitch over the 'Silent Partner'. Silent Partner Clove Hitch.jpg
Illustration of a clove hitch over the 'Silent Partner'.

As long as the clove hitch can feed over the drum, the rope will feed through the device. In a fall, the drum is back driven by the rope as the device slides down the rope; when the drum rotation exceeds a certain angular velocity, it locks off to the frame and the increase in friction induced between the stationary drum and the rope causes the clove hitch to rapidly tighten around the locked drum to arrest the fall.

The method used to lock the drum against the device frame is by the use of two straight knurl edge discs that are thrown outwards by centrifugal force as they ride on parallel ramps milled into the drum's enclosed outer periphery. Two light return springs act as centrifugal force trips and as return springs to reset the discs when the fall load is released and the device is unlocked. A simple nylon guide is used to ensure both discs activate simultaneously to jam the discs between each drum ramp and the frame's lock ring.

While the device works quite well, it suffers from rope drag that can prematurely tighten the clove hitch, so allowance must be made to reduce the hanging weight of the rope below the device. The rope diameter and elasticity is critical for operation, as higher than normal fall forces can be generated due to the rapid locking rate, in the order of 13 kN at runners and anchor points.

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Climbing protection is any of a variety of devices employed to reduce risk and protect others while climbing rock and ice. It includes such items as nylon webbing and metal nuts, cams, bolts, and pitons.

Traditional climbing Style of rock climbing

Traditionalclimbing, is a style of rock climbing in which a climber or group of climbers place all gear required to protect against falls, and remove it when a pitch is complete. Traditional bolted face climbing means the bolts were placed on lead and/or with hand drills. The bolts tend to be much farther apart than sport climbs. For example, a trad bolted route may have bolts from 15–75 feet apart. A sport route may have bolts from 3–10 feet apart, similar to a rock climbing gym. The term seems to have been coined by Tom Higgins in the piece "Tricksters and Traditionalists" in 1984. A trad climber is called a traditionalist.

Climbing harness item of climbing equipment that secures a person to a rope or an anchor point

A climbing harness is an item of climbing equipment for rock-climbing, abseiling, or other activities requiring the use of ropes to provide access or safety such as industrial rope access, working at heights, etc. A harness secures a person to a rope or an anchor point.

Tree climbing activity

Tree climbing is a recreational or functional activity consisting of ascending and moving around in the crown of trees.

Glossary of climbing terms List of definitions of terms and concepts related to rock climbing and mountaineering

This glossary of climbing terms is a list of definitions of terms and jargon related to rock climbing and mountaineering. The specific terms used can vary considerably between different English-speaking countries; many of the phrases described here are particular to the United States and the United Kingdom.

Rock-climbing equipment type of tool for climbing

A wide range of equipment is used during rock or any other type of climbing that includes equipment commonly used to protect a climber against the consequences of a fall.

Abseiling Rope-controlled descent of a vertical surface

Abseiling, also known as rappelling from French rappeler, 'to recall' or 'to pull through'), is a controlled descent off a vertical drop, such as a rock face, using a rope.

Free climbing form of climbing

Free climbing is a form of rock climbing in which the climber may use climbing equipment such as ropes and other means of climbing protection, but only to protect against injury during falls and not to assist progress. The climber makes progress by using physical ability to move over the rock via handholds and footholds. Free climbing more specifically may include traditional climbing, sport climbing, bouldering and most forms of solo climbing. Free climbing a multi-pitch route means free-climbing each of its pitches in a single session. At the end of each pitch, climbers are allowed to anchor themselves to belay stations and rest. If they fail climbing a pitch, they are allowed to use the rope to return to the beginning of that pitch and try it again.

Belaying Rock climbing safety technique

Belaying refers to a variety of techniques climbers use to exert tension on a climbing rope so that a falling climber does not fall very far. A climbing partner typically applies tension at the other end of the rope whenever the climber is not moving, and removes the tension from the rope whenever the climber needs more rope to continue climbing.

Lead climbing Competitive discipline of sports climbing

Lead climbing is a climbing style, predominantly used in rock climbing. In a roped party one climber has to take the lead while the other climbers follow. The lead climber wears a harness attached to a climbing rope, which in turn is connected to the other climbers below the lead climber. While ascending the route, the lead climber periodically connects the rope to protection equipment for safety in the event of a fall. This protection can consist of permanent bolts, to which the climber clips quickdraws, or removable protection such as nuts and cams. One of the climbers below the lead climber acts as a belayer. The belayer gives out rope while the lead climber ascends and also stops the rope when the lead climber falls or wants to rest.

Rock climbing Sport in which participants climb natural rock formations

Rock climbing is a sport in which participants climb up, down or across natural rock formations or artificial rock walls. The goal is to reach the summit of a formation or the endpoint of a usually pre-defined route without falling. Rock climbing is a physically and mentally demanding sport, one that often tests a climber's strength, endurance, agility and balance along with mental control. Knowledge of proper climbing techniques and use of specialized climbing equipment is crucial for the safe completion of routes.

Munter hitch

The Munter hitch, also known as the Italian hitch or the Crossing Hitch, is a simple adjustable knot, commonly used by climbers, cavers, and rescuers to control friction in a life-lining or belay system. To climbers, this knot is also known as HMS, the abbreviation for the German term Halbmastwurfsicherung, meaning half clove hitch belay. This technique can be used with a special "pear-shaped" HMS locking carabiner, or any locking carabiner wide enough to take two turns of the rope. The Munter hitch is named after Werner Munter, a Swiss mountain guide who popularised its use in mountaineering.

Ascender (climbing) Devices used for ascending, braking, or protection in climbing

An ascender is a device used for directly ascending a rope, or for facilitating protection with a fixed rope when climbing on very steep mountain terrain.

Prusik

A Prusik is a friction hitch or knot used to attach a loop of cord around a rope, applied in climbing, canyoneering, mountaineering, caving, rope rescue, ziplining, and by arborists. The term Prusik is a name for both the loops of cord and the hitch, and the verb is "to prusik". More casually, the term is used for any friction hitch or device that can grab a rope. Due to the pronunciation, the word is often misspelled Prussik, Prussick, or Prussic.

In rock climbing, an anchor can be any device or method for attaching a climber, a rope, or a load to the climbing surface - typically rock, ice, steep dirt, or a building - either permanently or temporarily. The intention of an anchor is case-specific but is usually for fall protection; primarily fall arrest and fall restraint. Climbing anchors are also used for hoisting, holding static loads, or redirecting a rope.

Single-rope technique Climbing technique

Single-rope technique (SRT) is a set of methods used to descend and ascend on the same single rope. Single-rope technique is used in caving, potholing, rock climbing, canyoning, roped access for building maintenance and by arborists for tree climbing, although to avoid confusion in the tree climbing community, many have taken to calling it "stationary" rope technique.

Autoblock

An autoblock is a rope device used in climbing and caving for both rappelling (downward) and ascending (upward).

Reverso (climbing equipment)

A Reverso is a belay device developed and patented by Petzl, used for example in rock-climbing and other activities which involves rope-work. Another version of this device is the Reversino, intended for use with thinner ropes.

Belay device Mechanical piece of climbing equipment

A belay device is a mechanical piece of climbing equipment used to control a rope during belaying. It is designed to improve belay safety for the climber by allowing the belayer to manage their duties with minimal physical effort. With the right belay device, a small, weak climber can easily arrest the fall of a much heavier partner. Belay devices act as a friction brake, so that when a climber falls with any slack in the rope, the fall is brought to a stop.

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