Ice screw

Last updated
An ice screw. Some modern screws like this one now have a handle to assist entry and removal, whereas early models did not. Ice screw.jpg
An ice screw. Some modern screws like this one now have a handle to assist entry and removal, whereas early models did not.

An ice screw is a threaded tubular screw used as a running belay or anchor by climbers on steep ice surface such as steep waterfall ice or alpine ice during ice climbing or crevasse rescue, to hold the climber in the event of a fall, and at belays as anchor points. [1] [2]

Contents

Design

Development of ice screws for the period 1924-2000 EishakenSchrauben.JPG
Development of ice screws for the period 1924-2000

Ice screws may come with one or more of the following: an in-built or separate ratchet mechanism to speed up placement, conical centre-hole to aid removal of ice cores, different lengths, different numbers of cutting teeth, different cutting angles, different surface finishes, and different size clip holes. Price and durability are usually design considerations too, as a usable rack of ice screws will be a significant financial investment for many climbers. Many titanium ice screws were initially made in the former Soviet Union using Cold War-era missile technology, but were generally too brittle, and so the majority of ice screws are now made of chromoly steel.[ citation needed ]

The strongest and most reliable type of ice screws currently available are the modern tubular ice screws which range in lengths from 10 to 23 cm. The approximate strength rating on a modern tubular ice screw is around 7  kN, and it has been found that short ice screws in good ice hold about 7-8 kN, no matter what the fall factor or configuration is. [3] The International Climbing and Mountaineering Federation drop test specifies that when multi-pitch lead climbing and the leader has only placed one screw (typically merely clipping one of the anchor screws) before climbing up a couple of meters and falling (a fall factor of 2), the screw must hold. [4] The dynamic ropes used in climbing can mitigate failure of an ice screw by keeping the impact forces low, especially if using a new rope that has not had any previous falls. It is rare that an ice screw fails in fall factors of 1 or less, if placed in good ice.

Two ice screws placed to form a solid climbing anchor point Iceclimbinganchor.jpg
Two ice screws placed to form a solid climbing anchor point

An older type of screw that is rarely used today is a pound-in ice screw, such as the 'snarg' and the 'warthog'. Instead of screwing these into the ice one would pound them in with a hammer from the ice tool, and then screw them out with the pick of an ice axe. The pound-ins have been largely replaced by modern tubular ice screws that are stronger and easier to use, although warthogs are being manufactured in Britain again for use in creating an anchor in frozen turf when no alternative anchor or placement is available. [5] [6] [7]

The latest ice screws incorporate replaceable tips, thereby increasing the useful life of the screw and enhancing placements. [8]

Placement

Climber placing an ice screw Ice Climber Grotto Falls Canmore.jpg
Climber placing an ice screw

It was once thought necessary or beneficial for ice-screws to be placed horizontally or with the hanger up for optimum hold. However, it has since been found experimentally that a screw placed with the tip angled up often holds as well or better. This surprising result is thought to be due to the previously underestimated role of the threads in holding the screw in place. However, horizontal placements are usually recommended.

Some climbers use tape slings to "tie-off" long ice-screws that have not been fully screwed into the ice, to reduce the leverage of a fall, which might bend or break the screw. There is some risk that such slings may move or be sliced by the screw's hanger. Some novel ice screws include a hanger that can be moved down the shaft, instead of using a sling. Placing a shorter screw is usually the preferred option, hence various lengths are available.

Other uses

Long ice-screws are now often used to create V-threads. By making two ice-holes that intersect, an inexpensive but strong cord (typically static climbing accessory cord or tape) can be threaded through, making a relatively safe and cheap anchor. This can be an attractive option at belays and when ice screws are in short supply. V-threads can be particular useful as rappel or abseil points where it is often necessary to leave the final anchor behind. A piece of wire - typically a piece of old coat hanger shaped for the purpose - or a stiff flexible purpose built tool with a small hook at one end and a hanging loop at the other end, is often used to aid threading of the cord.

In the Rosetta project, the European Space Agency equipped its lander with multiple ice screws to obtain stability on comet surface, but they failed to hold, and the lander bounced a significant distance from the initial landing site.[ citation needed ]

See also

Related Research Articles

<span class="mw-page-title-main">Mountaineering</span> Sport of mountain climbing

Mountaineering, mountain climbing, or alpinism is a set of outdoor activities that involves ascending mountains. Mountaineering-related activities include traditional outdoor climbing, skiing, and traversing via ferratas that have become sports in their own right. Indoor climbing, sport climbing, and bouldering are also considered variants of mountaineering by some, but are part of a wide group of mountain sports.

<span class="mw-page-title-main">Climbing wall</span> Artificial rock climbing wall

A climbing wall is an artificially constructed wall with manufactured grips for the hands and feet. Most walls are located indoors, and climbing on such walls is termed indoor climbing. Some walls are brick or wooden constructions, but on most modern walls, the material most often used is a thick multiplex board with holes drilled into it. Recently, manufactured steel and aluminum have also been used. The wall may have places to attach belay ropes, but may also be used to practice lead climbing or bouldering.

<span class="mw-page-title-main">Climbing harness</span> Item of climbing equipment

A climbing harness is a device which allows a climber access to the safety of a rope. It is used in rock and ice climbing, abseiling, and lowering; this is in contrast to other activities requiring ropes for access or safety such as industrial rope work, construction, and rescue and recovery, which use safety harnesses instead.

<span class="mw-page-title-main">Ice axe</span> Winter mountaineering tool

An ice axe is a multi-purpose hiking and climbing tool used by mountaineers in both the ascent and descent of routes that involve snow, ice, or frozen conditions. Its use depends on the terrain: in its simplest role it is used like a walking stick, with the mountaineer holding the head in the center of their uphill hand.

<span class="mw-page-title-main">Glossary of climbing terms</span> For rock climbing and mountaineering

Glossary of climbing terms relates to rock climbing, mountaineering, and to ice climbing.

<span class="mw-page-title-main">Ice climbing</span> Type of climbing with ice tools

Ice climbing is a climbing discipline that involves ascending routes consisting of frozen water. To ascend the route, the ice climber uses specialist equipment, particularly double ice axes and rigid crampons. To protect the route, the ice climber uses steel ice screws that require skill to employ safely and rely on the ice holding firm in any fall. Ice climbing routes can vary significantly by type, and include seasonally frozen waterfalls, high permanently frozen alpine couloirs, and large hanging icicles.

<span class="mw-page-title-main">Rock-climbing equipment</span> List of manmade gear

Rock-climbing equipment varies with the type of climbing undertaken. Bouldering needs the least equipment outside of shoes and chalk and optional crash pads. Sport climbing adds ropes, harnesses, belay devices, and quickdraws to clip into pre-drilled bolts. Traditional climbing adds the need for carrying a "rack" of temporary passive and active protection devices. Multi-pitch climbing adds devices to assist in ascending and descending fixed ropes. And finally aid climbing uses unique equipment.

<span class="mw-page-title-main">Aid climbing</span> Type of climbing

Aid climbing is a form of rock climbing that uses mechanical devices and equipment, such as aiders, for upward momentum. Aid climbing is the opposite of free climbing, which only uses mechanical equipment for protection, but not to assist in upward momentum. "Traditional aid climbing" involves hammering in permanently fixed pitons and bolts, into which aiders are clipped, whereas "clean aid climbing" avoids hammering, using only removable placements.

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

<span class="mw-page-title-main">Belaying</span> Rock climbing safety technique using ropes

Belaying is a variety of techniques climbers use to create friction within a climbing system, particularly 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.

<span class="mw-page-title-main">Top rope climbing</span> Type of rock climbing

Top rope climbing is a form of rock climbing where the climber is securely attached to a climbing rope that runs through a fixed anchor at the top of the climbing route, and back down to the belayer at the base of the climb. A climber who falls will just hang from the rope at the point of the fall, and can then either resume their climb or have the belayer lower them down in a controlled manner to the base of the climb. Climbers on indoor climbing walls can use mechanical auto belay devices to top rope alone.

<span class="mw-page-title-main">Nut (climbing)</span> Protection equipment in rock climbing

In rock climbing, a nut is a metal wedge threaded on a wire that climbers use for protection by wedging it into a crack in the rock. Quickdraws are clipped to the nut wire by the ascending climber and the rope threads through the quickdraw. Nuts come in a variety of sizes and styles, and several different brands are made by competing manufacturers. Most nuts are made of aluminum. Larger nuts may be threaded on Dyneema cord instead of wire, but this has become unusual.

<span class="mw-page-title-main">Rock climbing</span> Type of sport

Rock climbing is a sport in which participants climb up, across, or down natural rock formations or indoor climbing 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 the use of specialized climbing equipment is crucial for the safe completion of routes.

<span class="mw-page-title-main">Munter hitch</span> Adjustable knot used control friction in a belay system

The Munter hitch, also known as the Italian hitch, mezzo barcaiolo 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 hitch 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.

<span class="mw-page-title-main">Multi-pitch climbing</span> Type of climbing

Multi-pitch climbing is a type of climbing that typically takes place on routes that are more than a single rope length in height, and thus where the lead climber cannot complete the climb as a single pitch. Where the number of pitches exceeds 6–10, it can become big wall climbing, or where the pitches are in a mixed rock and ice mountain environment, it can become alpine climbing. Multi-pitch rock climbs can come in traditional, sport, and aid formats. Some have free soloed multi-pitch routes.

<span class="mw-page-title-main">Prusik knot</span> Type of knot

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 used to tie the hitch and the hitch itself, and the verb is "to prusik" or "prusiking". 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 above or onto a 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.

<span class="mw-page-title-main">Ice tool</span> Specialised modern ice axe

An ice tool is a specialized elaboration of the modern ice axe, used in ice climbing, mostly for the more difficult configurations. Ice tools are used two to a person for the duration of a pitch, and thus in some circumstances such as top-rope-anchored climbs, a pair may be shared among two or more people, where only one of them at a time is climbing. In contrast a classical "ice axe" is used one to a person for the hours or days a party is traveling across snow or glacier. In communities where it is common to refer to an "ice tool" simply as an "ice axe", classic "ice axes" are often referred to as "traveling axes", "walking axes", or "general mountaineering axes" to distinguish them from "tools".

<span class="mw-page-title-main">Belay device</span> 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.

<span class="mw-page-title-main">Abalakov thread</span> Ice climbing loop knot

The Abalakov thread, also known as a V-thread, A-thread, or 0-thread, is an ice protection technique named after its inventor, Soviet climber Vitaly Abalakov. The Abalakov thread is a common method of protecting oneself while ice climbing because it is easy to create, does not require the sacrifice of expensive gear, and can be very safe when used properly. An Abalakov thread is often used in multi-pitch ice climbing routes. Because of its safety and convenience, the Abalakov thread is considered one of the most significant innovations in ice climbing. It significantly expanded the scope of possible routes and abseiling safety.

References

  1. Cox, Steven M.; Kris Fulsaas, eds. (September 2003). Mountaineering: The Freedom of the Hills (7 ed.). Seattle: The Mountaineers. ISBN   0-89886-828-9.
  2. Semet, Matt; Mike Tea (2011). Climbing Dictionary. Seattle, USA: The Mountaineers Books. p. 124. ISBN   978-1-59485-502-3.
  3. Beverly and Attaway
  4. http://www.theuiaa.org/upload_area/cert_files/UIAA101_DynamicRopes.pdf [ dead link ]
  5. Ryan, Mick (December 2007). "The Warthog Rises Like A Phoenix From The Ashes". www.ukclimbing.com. Retrieved 5 December 2015.
  6. "Mountain Technology Warthog Turf Screw". www.needlesports.com. Retrieved 5 December 2015.
  7. "Snarg ice piton/screw". www.smhc.co.uk. Scottish Mountain Heritage Collection. Retrieved 5 December 2015.
  8. "E-Climb: Ice Screw Replaceable Tips". Archived from the original on 2011-07-10. Retrieved 2020-01-21.