Editing Ski (section)

===Modern skis===
[[File:Wilhelm Pohl Ski 003.JPG|thumb|Wooden skis with [[cable binding|cable (kandahar) bindings]] and bamboo poles]]
[[File:Cross-country equipment--Skate and Classic.jpg|thumb|Modern cross-country skis from synthetic materials, with poles and shoes.]]
Around 1850, artisans in Telemark, Norway, invented the cambered ski.<ref>Penn, Robert (2016) [https://books.google.com/books?id=wRqZCgAAQBAJ&pg=PT94 ''The Man Who Made Things Out of Trees''] W.W. Norton  {{ISBN|9780393253733}}</ref> 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 a sidecut that narrowed the ski underfoot while the tip and tail remained wider. This enabled the ski to flex and turn more easily.<ref name="Evolution of Ski Shape">Masia, Seth (2005) [https://books.google.com/books?id=clgEAAAAMBAJ&pg=PA33 "The Evolution of Modern Ski Shape"] ''Skiing Heritage'' pp. 33-37</ref>

Skis traditionally were hand-carved out of a single piece of hardwood such as [[hickory]], [[birch]] or [[Ash (tree)|ash]].<ref>[https://books.google.com/books?id=8NVGAQAAMAAJ&pg=PA498 "The Fine Points of a Ski"] ''Outing Magazine'' v69 #4:498 1917</ref> 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 the invention of the laminated ski.<ref name="Skiing Heritage Journal">Masia, Seth (2003) [https://books.google.com/books?id=rVgEAAAAMBAJ&pg=PA14 "The Splitkein Patent"] ''Skiing Heritage Journal'' p13-16</ref> 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.<ref name="Skiing Heritage Journal"/>

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 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,<ref name="Skiing Heritage Journal"/> 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, 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.

[[File:Cross-cut of laminated ski.jpg|thumb|Cross-cut of Howard Head's design (ca. 1965)]]
In 1950, [[Howard Head]] introduced the [[Head Standard]], constructed by sandwiching aluminium alloy around a [[plywood]] core. The design included steel edges (invented in 1928 in [[Austria]],<ref name="Evolution of Ski Shape"/>) 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.<ref name=fry>{{cite book|last=Fry|first=John|title=The story of modern skiing|year=2006|publisher=University Press of New England|location=Hanover|isbn=978-1-58465-489-6}}</ref>   
1962: a [[fibreglass]] ski, [[Kneissl]]'s White Star, was used by [[Karl Schranz]] to win two gold medals at the [[FIS Alpine World Ski Championships]].<ref name=fry/> By the late '60s fibreglass had mostly replaced aluminum.

In [[FIS Nordic World Ski Championships 1974|1974]], [[Magne Myrmo]] became the last world champion (Falun, 15&nbsp;km cross-country) using wooden skis.<ref name=Saur>Saur, Lasse (1999): ''Norske ski – til glede og besvær.'' Research report, Høgskolen i Finnmark.</ref><ref>{{cite web |last1=Kirkebøen |first1=Stein Erik |title=Magne Myrmo siste VM-vinner på treski |url=https://www.aftenposten.no/norge/i/vgdll/magne-myrmo-siste-vm-vinner-paa-treski |publisher=[[Aftenposten]] |access-date=9 November 2019 |language=no |date=15 April 2003}}</ref>

In 1975, the [[torsion box]] ski construction design is patented.<ref>{{cite web|last=Bjertaes|first=Gunnar|title=Patent number: 4005875 Ski construction of the torsion box type|url=https://patents.google.com/patent/US4005875|publisher=US Patent Office|access-date=15 November 2012}}</ref> The patent is referenced by Kästle, Salomon, [[Rottefella]], and [[Madshus]]. In 1993 [[Elan (company)|Elan]] introduced the [[Elan SCX]] model, skis with 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 cross-country skis have little sidecut.<ref>Kuzmin & Fuss (2013) [https://books.google.com/books?id=MQoKAgAAQBAJ&pg=PA172 Cross-country Ski Technology] ''Routledge Handbook of Sports Technology and Engineering''  pp171-188</ref> 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.<ref>Masia, Seth (2004) [https://books.google.com/books?id=_7YDcDEqBcEC&pg=PA18 Milestones and Detours in Ski Design] ''Skiing Heritage'' p18-22,36</ref> Other companies quickly followed suit, one Austrian ski designer admitting, "It turns out that everything we thought we knew for forty years was wrong."<ref name="Evolution of Ski Shape"/> [[Line Skis]], the first free-ski focused ski company<ref name="afpworldtour.com">{{cite web|url=http://www.afpworldtour.com/news/the-history-of-competitive-freeskiing|title=afpworldtour – the history of competitive freeskiing|access-date=2015-04-09|archive-date=2015-12-22|archive-url=https://web.archive.org/web/20151222233133/http://www.afpworldtour.com/news/the-history-of-competitive-freeskiing/|url-status=dead}}</ref> inspired the [[Freeskiing|newschool]] freeskiing movement with its [[twin-tip ski|twin-tip]] [[Skiboarding|ski boards]] in 1995.<ref>{{Cite web|url=http://lineskis.com/innovation|archive-url=https://web.archive.org/web/20131007000859/http://lineskis.com/innovation |url-status=dead |title=Skiing the wrong way since '95|archive-date=October 7, 2013}}</ref> 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.<ref name="afpworldtour.com"/><ref>{{Cite web|url=https://www.youtube.com/watch?v=x4A3FfgCRkU |archive-url=https://ghostarchive.org/varchive/youtube/20211211/x4A3FfgCRkU| archive-date=2021-12-11 |url-status=live|title=Salomon Freeski TV episode 3 – 1080|via=www.youtube.com}}{{cbignore}}</ref>