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62-489: A ski is a narrow strip of semi-rigid material worn underfoot to glide over snow. Ski may also refer to: Ski The word ski comes from the Old Norse word skíð which means "cleft wood", "stick of wood" or "ski". In Old Norse common phrases describing skiing were fara á skíðum (to travel, move fast on skis), renna (to move swiftly) and skríða á skíðum (to stride on skis). In Norwegian this word

124-457: A plywood core. The design included steel edges (invented in 1928 in Austria , ) and the exterior surfaces were made of phenol formaldehyde resin which could hold wax. This hugely successful ski was unique at the time, having been designed for the recreational market rather than for racing. 1962: a fibreglass ski, Kneissl 's White Star, was used by Karl Schranz to win two gold medals at

186-430: A "ski lubricant comprising paraffinic wax and hydrocarbon compounds containing a perfluorocarbon segment". The ability of a ski or other runner to slide over snow depends on both the properties of the snow and the ski to result in an optimum amount of lubrication from melting the snow by friction with the ski—too little and the ski interacts with solid snow crystals, too much and capillary attraction of meltwater retards

248-415: A cold ski, thereby diminishing the production of the melt layer. At the other extreme, when the snow is wet and warm, heat generation creates a thicker film that can create increased capillary drag on the ski bottom. Kuzmin and Fuss suggest that the most favorable combination of ski base material properties to minimize ski sliding friction on snow include: increased hardness and lowered thermal conductivity of

310-598: A correctly selected grip wax does not appreciably decrease the glide of skis that have proper camber for the skier's weight and for the snow conditions. There are two substances used for grip wax: hard wax and klister. Some skis are "waxless", having a fish-scale or other texture to prevent the ski from sliding backwards. Ski mountaineers use temporarily adhered climbing skins to provide uphill grip, but typically remove them for descent. Wax can be dissolved by non-polar solvents like mineral spirits . However, some commercial wax solvents are made from citrus oil , which

372-472: A crayon, applying a liquid wax or a spray wax. Hot applications of wax include the use of heat from an iron, infrared lamp, or a "hot box" oven. The role of glide wax is to adapt and improve the friction properties of a ski base to the expected snow properties to be encountered on a spectrum from cold crystalline snow to saturated granular snow. Modern ski bases often are made from ultra-high-molecular-weight polyethylene (UHMWPE) . Kuzmin asserts that UHMWPE

434-399: A downhill skiing context. Backcountry skiing, also known as off-piste skiing, is any form of skiing done outside of ski area boundaries. Most of the time this type of skiing is done with alpine touring skis , or telemark gear, where skiers take advantage of climbing skins and a detachable heel, to ski uphill. When the skier reaches the top of the area they want to ski down, they take off

496-521: A free heel to facilitate walking. Styles of Nordic skiing equipment include: Ski poles are commonly used in tandem with skis in a variety of types of skiing. They are typically used as a mechanism to help skiers in most types of skiing, giving additional maneuverability with support turning, walking, and getting up after falling. Ski maintenance encompasses four facets: binding adjustments, waxing, edge shaping, and base repair. Binding adjustment : Safety-release ski bindings require adjustment to fit

558-570: A lower coefficient of friction, but abrade more readily. Wax formulations combine three types of wax to adjust coefficient of friction and durability. From hard to soft, they include synthetic waxes with 50 or more carbon atoms, microcrystalline waxes with 25 to 50 carbon atoms and paraffin waxes with 20 to 35 carbon atoms. Additives to such waxes include graphite , teflon , silicon , fluorocarbons , and molybdenum to improve glide and/or reduce dirt accumulation. Glide wax can be applied cold or hot. Cold applications include, rubbing hard wax like

620-613: A much wider tip and tail than waist. When tipped onto their edges, they bend into a curved shape and carve a turn. Cross-country techniques use different styles of turns; edging is not as important, and skis have little sidecut. For many years, alpine skis were shaped similarly to cross-country, simply shorter and wider, but the Elan SCX introduced a radial sidecut design that dramatically improved performance. Other companies quickly followed suit, one Austrian ski designer admitting, "It turns out that everything we thought we knew for forty years

682-486: A new design technology was introduced with an outer hardwood shell completely encasing an inner layer of lighter wood, successfully eliminating spontaneously splitting glue lines. This early design eventually evolved into an advanced laminating technique which is referred to today as single-shell casing technology. In 1950, Howard Head introduced the Head Standard , constructed by sandwiching aluminium alloy around

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744-478: A sidecut that narrowed the ski underfoot while the tip and tail remained wider. This enabled the ski to flex and turn more easily. Skis traditionally were hand-carved out of a single piece of hardwood such as hickory or birch or ash . These woods were used because of their density and ability to handle speed and shock-resistance factors associated with ski racing. Because Europe's forests were dwindling, finding quality plank hardwood became difficult, which led to

806-409: A single long piece of suitable wood that is hand-carved to the required shape. Early designs were generally rectangular in cross-section, with the tip bent up through application of steam. Over time the designs changed, and skis were thinned out to the sides, or had prominent ridges down the center. In the history of skiing many types of skis have been developed, designed for different needs, of which

868-399: A variety of materials including carbon- Kevlar to make skis stronger, stiffer in twisting, lighter, and more durable. Ski manufacturing techniques allow skis to be made in one or a combination of three designs: Laminated skis are built in layers. Materials such as fiberglass , steel , aluminum alloy , or plastic are layered and compressed above and below the core. Laminated construction

930-563: A verb from the noun. Finnish has its own ancient words for skis and skiing: "ski" is suksi and "skiing" is hiihtää . The word suksi goes back to the Proto-Uralic period, with cognates such as Erzya soks , Mansi tåut and Nganasan tuta. The Sami also have their own words for "skis" and "skiing": for example, the Lule Sami word for "ski" is sabek and skis are called sabega . The Sami use cuoigat for

992-508: A walking stick to help the user maintain balance. Nordic ski technology was adapted during the early 20th century to enable skiers to turn at higher speeds. New ski and ski binding designs, coupled with the introduction of ski lifts to carry skiers up slopes, enabled the development of alpine skis. Meanwhile, advances in technology in the Nordic camp allowed for the development of special skis for skating and ski jumping . This type of ski

1054-429: Is a material applied to the bottom of snow runners, including skis , snowboards , and toboggans , to improve their coefficient of friction performance under varying snow conditions. The two main types of wax used on skis are glide waxes and grip waxes. They address kinetic friction —to be minimized with a glide wax—and static friction —to be achieved with a grip wax. Both types of wax are designed to be matched with

1116-464: Is less common for alpine and ski touring . During the 1980s, Bucky Kashiwa developed a new construction technique using a rolled stainless steel sheet forming three sides of a torsion box over a wooden core, with the base of the ski forming the bottom. Introduced in 1989, the Volant skis proved expensive to produce, and in spite of numerous positive reviews, the company never became profitable. In 1990,

1178-436: Is less toxic, harder to ignite, and gentler on the ski base. Ski wax may contain chemicals with potential health affects including per- and polyfluoroalkyl substances (PFASs). Levels of perfluorinated carboxylic acids , especially perfluorooctanoic acid (PFOA) , have been shown to increase in ski wax technicians during the ski season. When skiing, the friction between the snow and skis causes wax to abrade and remain in

1240-433: Is more important than surface chemistry for creating the optimum balance between a running surface that's too dry (not slippery enough) and too wet (ski subject to suction forces). In warm, moist snow, texture can help break the retarding capillary attraction between the ski base and the snow. Giesbrecht agrees that low wetting angle of the ski base is key and also emphasizes the importance of the degree of surface roughness at

1302-411: Is non-porous and can hold neither wax nor water, so there is no possibility for filling pores; furthermore, he asserts that UHMWPE is very hydrophobic, which means that wet snow does not appreciably retard the ski and that glide wax offers little additional ability to repel water. He notes that clear bases are more durable and hydrophobic than those with carbon content. The same author asserts that texture

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1364-422: Is the most widely used manufacturing process in the ski industry today. The first successful laminate ski, and arguably the first modern ski was the Head Standard , introduced in 1950, which sandwiched aluminum alloy around a plywood core. The Dynamic VR7 introduced a new construction method in which a smaller wooden core was wrapped in wet fibreglass, as opposed to pre-dried sheets of fibreglass being glued to

1426-412: Is the normal force of the ski on snow. Kinetic (or dynamic) friction occurs when the ski is moving over the snow. The coefficient of kinetic friction, μ k {\displaystyle \mu _{\mathrm {k} }} , is less than the coefficient of static friction for both ice and snow. The force required for sliding on snow is the product of the coefficient of kinetic friction and

1488-505: Is the tip, the middle is the waist and the rear is the tail. Skis have four aspects that define their basic performance: length, width, sidecut and camber. Skis also differ in more minor ways to address certain niche roles. For instance, mogul skis are softer to absorb shocks, powder skis are wider to provide more float and rocker skis bent upwards ( reverse camber ) at the tip and tail to make it easier to turn in deep and heavy snow. Skis have evolved from being made of solid wood to using

1550-538: Is usually pronounced [ˈʂiː] . In Swedish , another language evolved from Old Norse, the word is skidor (plural, pronounced [ˈɧîːdʊr] ; singular: skida ). The modern Norwegian word ski and the Swedish word skid have largely retained the Old Norse meaning in words for split firewood, wood building materials (such as bargeboards ) and roundpole fence . English and French use

1612-502: The FIS Alpine World Ski Championships . By the late '60s fibreglass had mostly replaced aluminum. In 1974 , Magne Myrmo became the last world champion (Falun, 15 km cross-country) using wooden skis. In 1975, the torsion box ski construction design is patented. The patent is referenced by Kästle, Salomon, Rottefella , and Madshus . In 1993 Elan introduced the Elan SCX model, skis with

1674-484: The micrometre scale as a function of snow temperature—cold snow favoring a smoother surface and wetter, warmer snow favoring a textured surface. Some authors question the necessity to use any glide waxes on modern ski bases. Cross-country skiers use a grip wax (also called "kick wax") for classic-style waxable skis to provide traction with static friction on the snow that allows them to propel themselves forward on flats and up hills. They are applied in an area beneath

1736-509: The 1990s, Swix chief chemist Leif Torgersen found a glide wax additive to repel pollen and other snow impurities—a problem with soft grip waxes during distance races—in the form of a fluorocarbon that could be ironed into the ski base. The solution was based on the work of Enrico Traverso at Enichem SpA , who had developed a fluorocarbon powder with a melting temperature just a few degrees below that of sintered polyethylene , patented in Italy as

1798-439: The 20th century, researchers addressed the twin problems of water and impurities adhering to skis during spring conditions. Terry Hertel addressed both problems, first with the novel use of a surfactant that interacted with the wax matrix in such a way as to repel water effectively, a product introduced in 1974 by Hertel Wax . Hertel also developed the first fluorocarbon product and the first spring-time wax that repels and makes

1860-466: The Salomon S9000 took the same basic concept but replaced the steel with plastics, producing a design they called "monocoque". Now referred to as the "cap ski" design, the concept eliminates the need to wrap the core and replaces this with a single-step process that is much less expensive to produce. Cap ski construction dominates alpine ski construction today. The classical wooden ski consists of

1922-526: The added value of a glide wax. Likewise, uni-directional textures (e.g. fish scale or micro-scale hairs) underfoot on cross-country skis can offer a practical substitute for grip wax for those skiers, using the classic technique. Johannes Scheffer in Argentoratensis Lapponiæ (History of Lapland) in 1673 gave what is probably the first recorded instruction for ski wax application He advised skiers to use pine tar pitch and rosin. Ski waxing

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1984-684: The base material to promote meltwater generation for lubrication, wear resistance in cold snow, and hydrophobicity to minimize capillary suction. These attributes are readily achievable with a PTFE base, which diminishes the value added by glide waxes. Lintzén reports that factors other than wax are much more important in reducing friction on cross-country skate skis—the curvature of the ski and snow conditions. Glide wax can be applied to alpine skis, snowboards, skate skis, classic skis, back-country skis, and touring skis. Traditional waxes comprise solid hydrocarbons. High-performance "fluorocarbon" waxes also contain fluorine, which substitutes some fraction of

2046-434: The base of a ski and increase friction, indicating the use of harder waxes. Conversely, older, warmer, and denser snows present lower friction, in part due to increased grain size, which better promotes a water film and a smoother surface of the snow crystals for which softer waxes are indicated. Colbeck offers an overview of the five friction processes of skis on snow. They are the: 1) resistance due to plowing of snow out of

2108-461: The cambered ski. This ski arches up in the middle, under the binding, which distributes the skier's weight more evenly across the length of the ski. Earlier plank-style skis had to be thick enough not to bow downward and sink in the snow under the skier's weight. This new design made it possible to build a thinner lighter ski, that flexed more easily to absorb the shock of bumps, and that maneuvered and ran faster and more easily. The design also included

2170-445: The climbing skins and make the necessary preparations to ski back down. Backcountry terrain can also be accessed with standard alpine equipment by riding a lift uphill at a ski resort and then leaving the resort boundary. However, this is more commonly known as sidecountry because of its immediate access from a ski lift. In Nordic skiing the skier is not reliant on ski lifts to get up hills, and so skis and boots tend to be lighter, with

2232-510: The core (essentially replacing metal sheets). The result was a torsion box , which made the ski much stronger. The VR7, and its more famous follow-on VR17, was the first fibreglass ski that could be used for men's racing, and quickly took over that market. Over time, materials for both the core and torsion box have changed, with wood, various plastic foams, fibreglass, kevlar and carbon fiber all being used in different designs. Torsion box designs continue to dominate cross-country ski designs, but

2294-403: The first commercial ski lubricants, such as Black Dope and Sierra Lighting ; both were mainly composed of sperm oil , vegetable oil and pine pitch. However, some instead used paraffin candle wax that melted onto ski bases, and these worked better under colder conditions. Pine tar on wooden ski bases proved effective for using skis as transport over the centuries, because it fills the pores of

2356-720: The following is a selection. Alpine skis, also called downhill skis, are skis designed specifically for lift-assisted resort runs. Ski design has evolved enormously since the beginnings of the modern sport in mid-19th-century Norway. Modern skis typically have steel edges, camber, side cut, and possibly reverse camber. During the 1990s side cut became more pronounced to make it easier to carve turns. Alpine skis typically have fixed-heel bindings. Specialised types of alpine skis exist for certain uses, including twin-tip skis for freestyle skiing , slalom skis , GS Skis , powder skis, telemark skis and monoskis . The following table shows different kinds of alpine ski types and their uses within

2418-486: The glide wax affects the melting of the snow to lubricate its passage over the surface and its ability to avoid suction from meltwater in the snow. Too little melting and sharp edges of snow crystals or too much suction impede the passage of the ski. A tipping point between where crystal type dominates sliding friction and moisture content dominates occurs around 26 °F (−3 °C). Harder waxes address colder, drier or more abrasive snow conditions, whereas softer waxes have

2480-678: The ground, the flakes immediately begin to undergo transformation (called metamorphism ), owing to temperature changes, sublimation , and mechanical action. Temperature changes may be from the ambient temperature, solar radiation, rainwater, wind, or the temperature of the material beneath the snow layer. Mechanical action includes wind and compaction. Over time, bulk snow tends to consolidate —its crystals become truncated from breaking apart or losing mass with sublimation directly from solid to gas and with freeze-thaw, causing them to combine as coarse and granular ice crystals. Colbeck reports that fresh, cold, and man-made snow all interact more directly with

2542-470: The heavy hardwood skis made before. Although lighter and stronger, laminated skis did not wear well. The water-soluble glues used at the time failed; they warped and split along the glue edges (delaminating) frequently and rapidly. In 1922, a Norwegian skier, Thorbjorn Nordby, developed strong waterproof glue which stopped the problem of splitting, therefore developing a much tougher laminated ski. Research and design of laminated skis rapidly progressed. In 1933,

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2604-502: The hydrogen atoms in the hydrocarbons with fluorine atoms to achieve lower coefficients of friction and higher water repellency than the pure hydrocarbon wax can achieve. Wax is adjusted for hardness to minimize sliding friction as a function of snow properties, which include the effects of: A variety of glide waxes are tailored for specific temperature ranges and other snow properties with varying wax hardness and other properties that address repellence of moisture and dirt. The hardness of

2666-528: The invention of the laminated ski. Beginning in 1891, skimakers in Norway began laminating two or more layers of wood together to make lighter cross country running skis. These evolved into the multi-laminated high-performance skis of the mid-1930s. A laminated ski is made of two types of wood glued together. A top layer of soft wood is glued to a thin layer under a surface of hardwood. This combination created skis which were much lighter and more maneuverable than

2728-460: The normal force: F k = μ k F n {\displaystyle F_{k}=\mu _{\mathrm {k} }F_{n}\,} . Both the static and kinetic coefficients of friction increase with colder snow temperatures (also true for ice). Snowflakes have a wide range of shapes, even as they fall; among these are: six-sided star-like dendrites , hexagonal needles, platelets and icy pellets. Once snow accumulates on

2790-454: The original Norwegian spelling ski , and modify the pronunciation. Before 1920, English often called them skee and snow-shoe . In Italian , it is pronounced similarly to Norwegian, but the spelling is modified accordingly: sci [ˈʃi] . Portuguese and Spanish adapt the word to their linguistic rules: esqui and esquí . In German, spellings Ski and Schi are in use, both pronounced [ˈʃiː] . In Dutch ,

2852-595: The plain and skinned short ski. Finnish names for these are lyly and kalhu for the long and short ski. The seal hunters at the Gulf of Bothnia had developed a special long ski to sneak into shooting distance to the seals' breathing holes, though the ski was useful in moving in the packed ice in general and was made specially long, 3–4 meters, to protect against cracks in the ice. This is called skredstång in Swedish. Around 1850, artisans in Telemark, Norway, invented

2914-421: The running surface slick for spring time alpine ski and snowboard. This technology was introduced to the market in 1986 by Hertel Wax. In 1990, Hertel filed for a U.S. patent on a "ski wax for use with sintered-base snow skis", containing paraffin, a hardener wax, roughly 1% per-fluoroether diol, and 2% SDS surfactant. Trademarks for Hertel waxes are Super HotSauce, Racing FC739, SpringSolution and White Gold. In

2976-429: The ski bottom and the wax that is applied to reduce sliding friction or achieve adequate grip. Typically, a sliding ski melts a thin and transitory film of lubricating layer of water, caused by the heat of friction between the ski and the snow in its passing. Colbeck suggests that the optimum water film thickness is in the range between 4 and 12 μ m . However, the heat generated by friction can be lost by conduction to

3038-466: The ski. Before a ski can slide, it must overcome the maximum value static friction, F m a x = μ s F n {\displaystyle F_{max}=\mu _{\mathrm {s} }F_{n}\,} , for the ski/snow contact, where μ s {\displaystyle \mu _{\mathrm {s} }} is the coefficient of static friction and F n {\displaystyle F_{n}\,}

3100-422: The skier's foot and extending, somewhat forward, that is formed by the camber of the classic ski, called the "grip zone" (or "kick zone"). The presence of camber allows the skis to grip the snow, when the weight is on one ski and the ski is fully flexed, but minimize drag when the skis are weighted equally and are thus less than fully flexed. Grip waxes are designed for specific temperature ranges and types of snow;

3162-426: The snow pack until spring thaw. Then the snowmelt drains into watersheds, streams, lakes and rivers, thereby changing the chemistry of the environment and the food chain. PFASs in ski wax are heat resistant, chemically and biologically stable, and thus environmentally persistent. They have been shown to accumulate in animals that are present at ski venues. The International Ski Federation (FIS) announced to introduce

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3224-533: The snow, especially during icy conditions. The angle from the plane of the bottom of the ski is set, depending on the type of skiing anticipated, as follows: Edge shaping may be done daily with carborundum or diamond stone to remove imperfections. Tuning the edges requires a series of applications of sharpening tools and stones, working at approximately right angles along the metal edge. Base repair : Ski base repair has three levels: cleaning, filling imperfections, and surface preparation. Ski wax Ski wax

3286-579: The varying properties of snow, including crystal type and size, and moisture content of the snow surface, which vary with temperature and the temperature history of the snow. Glide wax is selected to minimize sliding friction for both alpine and cross-country skiing. Grip wax (also called "kick wax") provides on-snow traction for cross-country skiers, as they stride forward using classic technique . Modern plastic materials (e.g. high-modulus polyethylene and Teflon), used on ski bases, have excellent gliding properties on snow, which in many circumstances diminish

3348-453: The verb "to ski". Skis appeared before the wheel , with the oldest wooden skis found in Russia (c. 6300–5000 BCE), Sweden (c. 5200 BCE) and Norway (c. 3200 BCE) respectively. These early skis were not designed for recreation, transportation, or speed; their sole purpose was to keep the user on top of the snow while hunting or when at war . Early skis were generally accompanied by

3410-461: The way, 2) deformation of the snow over which the ski is traveling, 3) lubrication of the ski with a thin layer of melt water, 4) capillary attraction of water in the snow to the ski bottom, and 5) contamination of the snow with dust and other non-slippery elements. Plowing and deformation pertain to the interaction of the ski, as a whole, with the snow and are negligible on a firm surface. Lubrication, capillary attraction and contamination are issues for

3472-405: The weight and height of the skier. Annual maintenance assures that settings continue to be correct. For rental skis, such an adjustment is required for each change of customers. Waxing : Most ski wax minimizes gliding friction on snow. " Grip wax " promotes grip on snow for cross-country skis. Wax may be applied in three ways, melting on, rubbing on and as a paste. Edge shaping : Edges engage

3534-414: The wood and creates a hydrophobic surface that minimizes suction from water in the snow, yet has sufficient roughness to allow traction for forward motion. In the 1920s and 30s, new varnishes were developed by European companies as season-long ski bases. A significant advance for cross country racing was the introduction of klister, for good traction in granular snow, especially in spring conditions; klister

3596-901: The word is ski and the pronunciation was originally [ˈɕiː] as in Norwegian, but since approximately the 1960s changed to [ˈskiː] . In Welsh the word is spelled sgi . Many languages make a verb form out of the noun, such as to ski in English, skier in French, esquiar in Spanish and Portuguese, sciare in Italian, skiën in Dutch, or Schi laufen or Schi fahren (as above also Ski laufen or Ski fahren ) in German. Norwegian and Swedish do not form

3658-436: Was also documented in 1761. In 1733 the use of tar was described by Norwegian colonel Jens Henrik Emahusen. In the 1740s Sami people use of resin and tallow under their skis is recorded in writing. Beginning around 1854, California gold rush miners held organized downhill ski races. They also discovered that ski bases, smeared with lubricants brewed from vegetable and/or animal compounds, increased speed. This led to some of

3720-455: Was invented and patented in 1913 by Peter Østbye . In the early 1940s Astra AB , a Swedish chemical company, advised by Olympic crosscountry skier Martin Matsbo , started the development of petroleum-based waxes, using paraffin wax and other admixtures. By 1952, such noted brands as Toko, Swix and Rex were providing an array of color-coded, temperature-tailored waxes. In the last quarter of

3782-556: Was used at least in northern Finland and Sweden until the 1930s. On one leg, the skier wore a long straight non-arching ski for sliding, and on the other a shorter ski for kicking. The bottom of the short ski was either plain or covered with animal skin to aid this use, while the long ski supporting the weight of the skier was treated with animal fat in similar manner to modern ski waxing . Early record of this type of skis survives in works of Olaus Magnus . He associates them to Sami people and gives Sami names of savek and golos for

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3844-469: Was wrong." Line Skis , the first free-ski focused ski company inspired the newschool freeskiing movement with its twin-tip ski boards in 1995. The first company to successfully market and mass-produce a twin-tip ski to ski switch (skiing backwards) was the Salomon Group , with its 1080 ski in 1998. Described in the direction of travel, the front of the ski, typically pointed or rounded,

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