Talk:Ski

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Alpine ski

There are many missunderstandigs of skiing mechanic (forces, bending deformations of skis, torsional deformations of skis)in general and also in porfessional public. Statment like "While old fashioned "straight skis" which had little side cut could carve turns, great leg strength was required to generate the enormous pressure necessary to flex them into a curved shape, a shape called reverse camber. " reapear in the text. This is copletly wrong and misleading. It is even contradictory to the very next sentence "When a modern ski is tilted on to its edge, a gap is created between the ground and the middle of the ski (under the binding) as only the sides near the tip and the tail touch the snow. Then, as the skier gently applies pressure, the ski bends easily into reverse camber." Therefore I ask some native speaker to correct this and write it in proper English (not like mine:-) taking into account following:

1. Bending of the ski on the edge depends on sidecut only - make following experiment: stand still on the slope with your skis edged. Ask one of your friends to observe the ski and anotherone to climb on your back. Even in moderatly soft snow, the ski will not bend more because of additional load, this can happen only in deep powder. 2. Skier can apply pressure to the ski. This statment contradict with Newtonian mechanic. Forces on skier are result of acceleration (speed and turn radius) and not result of muscularactivity. Inertia of body mass is producing force to the ski! Therefore independent of ski construction or skiers ability, skiing the same curve with the same speed will produce exacly the same force on skis. Corect statement is: Inertial forces on skier generate load on the ski (please help to repair this).

3. Carving turn is a geometrical problem. Carving turn is possible only when curve of the turn and curve of the ski edge on the snow have same radius AND same center. Practicaly edging angle (angle between running base and snow surface) can be between 0 and 60 degrees and therefore carving radius can be between sidecut radius and 1/2 of sidecut radius (Carving radius = cos (edging angle)* sidecut radius) (see also http://en.wikipedia.org/wiki/Carve_turn)

4. "The ski is turned by applying pressure, rotation and edge angle". I have already explained why applying pressure is not possible - it is the end result, not the reason. There are two types of turns: carving turn and skidding turn with different mechanics. I have explained carving turn already, so let me explain skidding turn in short: Skidding turn starts with rotating skis out of direction of skiing by either external momentum (ski pole...) or internal twist of skiers body. From this point on diffeence in edging friction between portion of the ski in front of center of gravitiy and behind center of gravity (please note - not ski boot, but center of gravity) starts to rotate the skier. If center of gravity is behind 'neutral point' the ski will rotate to support the turn (it will rotate in the direction of the turn). At the same time skier must increase edging angle to increase overal edging friction. This will result friction force pependecular to the ski. Because the ski is not pointed in the direction of skiing, only one component of edging friction will be pependecular to direction of skiing and will force skier into curved path. The other component will be used for drag only and will reduce acceleration because of 'downhill' orientation of the skier during the turn. At the end of the turn skier moves the center of gravity forward of neutral point and resulting difference in friction between part of the ski in fornt and behind center of gravity will procude momentum that will stop rotation and skier can therefore sart another turn or continue to ski straight.

Above explanations and theory is supported by measurements and this model is used in the industry (in R&D departments, not in marketing or racing departments :-)

Because this article is rated important and Strat-class at the same time, please translate above into more english form

Jurij Franko — Preceding unsigned comment added by Jurefr (talk • contribs) 17:52, 24 January 2011 (UTC)[reply]

Old myth

I deleted the following nonsense:

"Snow skis glide on snow because downward pressure, as well as heat from surface friction, melts a thin layer of snow directly under the ski. This creates a very thin layer of water directly under the ski upon which the ski glides. Ski wax is used to decrease drag by increasing the water repellent properties of the base."

If anything it could be rewritten to make clear that the reason a lot of things slide on ice is very complicated, and that although it was previously thought to be the case melting due to friction or pressure does not play a role, even in ice skating. —Preceding unsigned comment added by 62.243.195.138 (talk) 19:16, 13 January 2009 (UTC)[reply]


History of ski or skiing

Are the latest edits here better suited under skiing rather than "ski"? - See revision WinterOfDiscontent 09:38, 8 December 2006 (UTC)[reply]

I think they should be moved to skiing, since they are more about the sport than the equipment. This article should be "a technical article" about different ski types. But I also think this article should have a history of skiis.Labongo 19:28, 8 December 2006 (UTC)[reply]

Backcountry & Alpine Separated?

Is the difference between the backcountry ski and the alpine touring ski pronouced enough to justify two separate categories? The two seem to be functionally identical. The descriptions only suggest differences in the manufacturers or the part of the world they are used in. I suggest combining the two!


Much may better be moved to ski or skiing. Patrick 13:01 Jan 6, 2003 (UTC)

Exactly! The austrian alpine history can also be placed under alpine skiing.

This article needs to be synchronised and heavily cross-linked with the http://en.wikipedia.org/wiki/Skiing page.

"Telemark" is a county in Norway, and the Telemark should cover that IMHO.

"Telemark" is also a downhill skiing event with traditions from Telemark, and should have an article, I would suggest "Telemark skiing"

"Telemark" is not a synonym for "ski" YES Renebach 12:19, 19 June 2006 (UTC)[reply]

What about water skiing ?

That should be added elsewere ! Renebach 12:46, 19 June 2006 (UTC)[reply]

We should have one top topic (top entry topic): skiing Renebach 12:46, 19 June 2006 (UTC) as it exists already ! The topic there should be improved:[reply] 

  - The olympic disciplines  This should be documented in more detail on the skiing page
 downhill, super geant , geant, slalom. I can write something, but I'd like the author(s) of the skiing page to contact me
  - ski-cross (4 racers against each other)
  - jumping - arials (twists and summersault (spell ')
  - dancing - ski ballet ?? making figures
  - freestyles (combination of jumps and moguls)

2. snowboards 

  - general description (style, material, ...)
  - olympic desciplines: slalom, pipes, ... ??

...

5. water skiing

6. MISC. other definitions: ski for snow-mobiles 

                           ski for the ski-bobs (sitting on a frame with two skis, one being connected to a handle-bar), mono-ski (two feets looking forward on one larger ski)

Egil 00:52 Jan 26, 2003 (UTC)

Since much of the material was historic, I moved it all to History of skiing, and also added a few minor articles on Sondre Norheim and Morgedal.

I've also made a page for the county [[Telemark] akin to other couties in Norway. The Telemark ski is now just that. Telemark skiing is the modern sport.

Wrt. the Telemark ski, I did not rewrite the description, but perhaps it should be rewritten to say that the Telemark ski has a "sway" or "swing" in the profile? I'm not sure what the common english term for this is. Because that is the crux.

Egil 11:26 Jan 27, 2003 (UTC)

The local slang for "Twin-slip skiing" is "freestyle skiing" or simply "freestyle". (By Local, I mean in Canada. I suspect the same slang is used across North America.) I haven't heard the term "twin-slip" until reading this page.. (which doesn't make it wrong, of course.) -g 01:22:14 Dec 20, 2004 (UTC)

I just made a new section for backcountry skiing. The reason I did this is that standard alpine skiing is done via lift access at a ski area/resort. Whereas backcountry skiing is accessed by climbing uphill similarly to nordic skiing but then skied down in a regular alpine fashion without stepping foot in a lift access skiing area. Burger101(talk) 20:06, 21 February 2021 (UTC)[reply]

I also just added an introduction to the alpine section and a few more skis that fall within the alpine category. Burger101(talk) 11:00, 21 February 2021 (UTC)[reply]

Bigfoot and Skiboards are not skis

No offense to those who may like these things, but I don't think we can call everything that straps to your foot and slides on the snow a ski. Aside from being poorly written and lacking any citations, this paragraph just doesn't belong here. This is a page about skis, not every novel product that may resemble a ski (of which there are far more than just the bigfoot and ski board). I'd suggest creating a separate page on Variations of the Ski or Alternative Winter Sports, and restrict the content on this page to, oh I don't know... skis? Below is a copy of what I deleted. --Atomicskier 22:59, 3 January 2007 (UTC)[reply]

... but the article starts with "A ski is a long flat device worn on the feet designed to help the wearer slide smoothly over snow". When is a wakeboard a monoski?

===Skiboards and Bigfoots ===
Bigfoots
Skiboards are built like tiny snowboards, typically 90-130cm in length, marketed originally as a more convenient method of skiing, but now for those who want extreme freestyle on the slope. True skiboard bindings are mounted in the center, are non-releasable, and require an ankle leash due to the absence of a braking system. Before this time period the Austrian ski company Kneissl produced a short, foot shaped ski called the Bigfoot. The Bigfoot was popular during the late 80s and early 90s. The Line ski company has manufactured skiboards since the mid 1990s and is credited with the creation of the first modern skiboard. Skiboards, when at going at high speed and on the flat bottom of the skiboard, tend to vibrate, and thus some people prefer to skiboard on the edge of the skiboard in order to decrease the vibration and have more control of the skiboard. Others, especially veterans, find the vibration to be a non issue. As with skis, the edges can still be used to decrease contact with the snow (and thus increase speed).
Due to their much shorter size, skiboards can be easier to learn on, and much more agile, than conventional skis. Compared with traditional skis, they can make blue trails as easy as green; make moguls a non-issue; facilitate uphill climbing; aid tricks (by being easier to turn in the air); and be carried and stored more easily.''

Carving on straight skis

The following revision keeps getting thrown in, "Straight skis can not be used to carve turns short enough to be practicaly useful for simple geometrical reason." I'd guess this was written by someone who either has never skied on a straight ski or never learned how to do it right. If you don't believe straight skis can make a tight carve, watch Glen Plake on his 218 straights ski circles around pros on shaped skis.--Atomicskier 16:18, 5 February 2007 (UTC)[reply]

Carving on straight skis

Hi Atomicskier! I have been skiing straights skis for quite long time togehter with world cup racers:-) The whole idea of carving skis started with geometrical definition: Threre is no skidding if every point of the ski edge travels trough the single point on the snow surface, hope you agree! This is only possible when radius of a turn is equal to the shape of the ski edge on the snow. It is common misunderstanding that the ski will deform proportional to the force of the skier to surface. But take any ski (straight or carving) and press it flat to the flat surface (table, floor, snow) and you will learn that from the moment the ski underfoot touches the surface, it will not deform any more. The same will hapen if you press it angulated. So the deformation of the ski is not proportional to the load any more but is defined by sidecut only. The shape of the ski edge on the slope when the ski is angulated is aproximately sidecut radius * cos (angulation angle). As a result, straight ski with sidecut of 50m will carve turn with radius between 25 and 50 (60 degrees angulation) and ski with sidecut radius of 12 m will carve between 6 and 12m radius. There is a lot more stuff behind this short explanation but you can check my short comments in http://skiinghistory.org/sidecut.html. I tried to be very precise in straight ski carving definition and I hope now you understand why. If you need additional explanations or have any other questions, let me know.

Jurij Franko —The preceding unsigned comment was added by Jurefr (talk • contribs) 15:36, 9 February 2007 (UTC).[reply]

Design features/explanation

I've been shopping for new skis and so trying to understand what attributes to look for for particular kinds of skiing. Here are some things/terms that this page should explain:

  • Width under foot (more for flotation... I'm not sure why less is good...)
  • Sidecut (How much less is the width under foot than the width at the tips/tails
  • Camber
  • Bending stiffness (I've been told that more is good for high speed, less is good for not getting tangled in moguls.)
  • Torsional stiffness (I think more is better but I imagine it is more expensive)
  • Turning radius (Presumably this is a function of camber and sidecut.
  • "Rocker skis" for powder. The tip and tail are concave up rather than down. Apparently this derives from water ski design.

There are more. —Ben FrantzDale (talk) 17:50, 30 November 2008 (UTC)[reply]

Design features explanation
  • Width under foot gives you floatation in deep snow and more stability at great speeds, but slows down transition from one turn to another - therefore racers uses as narrow skis as possible (FIS rules are the limit)
  • Sidecut and ski length determine the ski turning radius - shorter ski gives smaller radius. So does greater sidecut.
  • Bending stiffness is somehow complex to explain. In a racing skis stiffer ski gives you more rebound at the end of turn, but too stiff ski would limit the capability of making tight carved turns. For amateurs stiffer ski is a better "platform", but too stiff ski is hard to be rotated by feet, and so on...
  • Torsional stiffness gives the ski more grip on hard, icy slopes. Also the ski becomes more "aggresive" when entering turns.
  • Turning radius (if talking about the radius given by the ski manufacturer) is a function of sidecut and ski length - camber affects the real turning radius (more you bend the ski, tighter the turn will be), while the parameter given by manufacturer is rather a kind of indicator of what the ski is capable of. The smaller the radius is, the ski turns faster, but is not stable at high speeds. :Long radius gives you more stability at high speeds, but is less agile.
Hope it will help a little, but someone will have to translate it into english first ;)
Devastator pc (talk) 10:31, 2 December 2008 (UTC)[reply]
Thanks for the reply; that's really helpful. That all sounds plausible. I'm curious what you mean by "rebound at the end of [a] turn". —Ben FrantzDale (talk) 12:11, 8 December 2008 (UTC)[reply]
by the term "rebound" I mean the effect when the skier ends the turn, and the ski "unbends" (becomes flat again) giving the skier additional speed. Devastator pc (talk) 17:22, 8 December 2008 (UTC)[reply]

No mention of ski maintenance

Maybe this article should include a section on the maintenance of ski equipment? Ski and snowboard equipment require much more maintenance than most equipment found in other sports/activities. Maybe just a picture of someone tuning a ski on a ski tuning machine? I do not have one. - tbone (talk) 17:49, 2 December 2010 (UTC)[reply]

I just started a maintenance section talking about waxing, edging, and base repair. Some photos would definitely be great if someone has any. User:Burger101 (talk) 1:24, 22 February 2021 (UTC)

Thank you for your efforts, Burger101. Unfortunately, your contributions have two problems:
  1. WP is not a how-to manual. See WP:NOTHOWTO
  2. Your sources are WP:BLOGS, which are not a preferred reliable source, unless the blogger is a published author.
I hope that this information can guide you in restructuring an otherwise meritorious addition. Cheers, HopsonRoad (talk) 16:23, 22 February 2021 (UTC)[reply]

Hey HopsonRoad, Thank you for your concern however I would like to note that the information I provided on ski maintenance is not a how-to manual, it more a definition of the different types of ski maintenance. Also, I would like to mention only one reference in this new section is from a blog. The one blog post was written by Steve Kopitz, the CEO of Summit Sports and operator of the Skis website at the time, who has many years of experience in the ski industry. User:Burger101 (talk) 7:26, 26 February 2021 (UTC)

Hi, Burger101, and thanks for your reply. I'm fine with the facts presented and the structure of presentation. It's just that WP:TONE suggests that, "Articles and other encyclopedic content should be written in a formal tone." There are a few instances where "you" and "your" could be omitted to avoid the "how-to" feel of the language. As to references, only one is a blog, but it is used in three of the four times where a reference is cited. Perhaps you can find the same material covered in ski magazines, which would count a reliable sources. I searched on "ski tuning" under books and got several hits. Cheers, HopsonRoad (talk) 14:19, 26 February 2021 (UTC)[reply]
Hey HopsonRoad, Thanks for the suggestions, ill see if I can find any good references on the matter as well as change the tone in the new section. User:Burger101 (talk) 15:08, 26 February 2021 (UTC)

Sondre?

Hi,

The section "Modern Skis" reference Norheim, but without his full name and without linking to his wiki bio page (http://en.wikipedia.org/wiki/Sondre_Norheim), something of an omission, I think, esp. wrt. the first point; it makes the paragraph somewhat enigmatic. PLS some EN native speakers correct this ...?

MVH, T 2001:4610:A:5E:0:0:0:713F (talk) 01:37, 15 March 2015 (UTC)[reply]

'The late 1900s'

Not clear what this means - it isn't natural English, at least when referring to a period that ended only 15 years ago. If it means 'the late 20th century', that's what should be there. I've just found (and corrected) another piece of incorrect English ('has been used' referring to a period that has now ended - that should read 'was used'), and now suspect this whole article was written by a non-native user of English. Especially on a subject as important as ski-ing, that's really not a good idea!213.127.210.95 (talk) 16:43, 31 March 2016 (UTC)[reply]

Elsewhere, it was rendered as 1800s, in fact such skis were being manufactured as late as 1930. Non-native speakers are welcome to edit here with the understanding, as with all editors, that some cleanup may be required! User:HopsonRoad 00:18, 1 April 2016 (UTC)[reply]

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