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Slouppi • View topic - Use of 'chalk' in rock climbing: sine qua non or myth?

Slouppi

Rock climbing and Bouldering in Finland
It is currently Wed Sep 26, 2018 01:47

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 Post subject: Use of 'chalk' in rock climbing: sine qua non or myth?
PostPosted: Tue May 16, 2006 11:35 
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Li, F X. Margetts, S. Fowler, I. kirjoittavat lehdessä nimeltä Journal of Sports Sciences. 19(6):427-32, 2001 Jun

Abstract:
Magnesium carbonate, or 'chalk', is used by rock climbers to dry their hands to increase the coefficient of friction, thereby improving the grip of the holds. To date, no scientific research supports this practice; indeed, some evidence suggests that magnesium carbonate could decrease the coefficient of friction. Fifteen participants were asked to apply a force with the tip of their fingers to hold a flattened rock (normal force), while a tangential force pulled the rock away. The coefficient of friction--that is, the ratio between the tangential force (pulling the rock) and the normal force (applied by the participants)--was calculated. Coating (chalk vs no chalk), dampness (water vs no water) and rock (sandstone, granite and slate) were manipulated. The results showed that chalk decreased the coefficient of friction. Sandstone was found to be less slippery than granite and slate. Finally, water had no significant effect on the coefficient of friction. The counter-intuitive effect of chalk appears to be caused by two independent factors. First, magnesium carbonate dries the skin, decreasing its compliance and hence reducing the coefficient of friction. Secondly, magnesium carbonate creates a slippery granular layer. We conclude that, to improve the coefficient of friction in rock climbing, an effort should be made to remove all particles of chalk; alternative methods for drying the fingers are preferable.

Kaikkea sitä tiedemiehet pystyy osoittamaan. Liekö itse kiipeilijöitä. :)


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PostPosted: Tue May 16, 2006 11:47 
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Joined: Sun Apr 02, 2006 11:56
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Location: Helsinki
jotenkin tuntuu siltä että tässä "tieteellisessä tutkimuksessa" tutkijoilla ei ollut mitään hajua mankan käytöstä joten laitettiin sitä sitten oikein kunnolla. :roll:
Ainakin omasta mielestäni mankka huonontaa kitkaa VAIN jos sitä on liikaa käsissä.

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ATC; Addicted To Climb


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 Post subject:
PostPosted: Tue May 16, 2006 12:10 
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Joined: Wed Dec 19, 2001 02:00
Posts: 333
Location: nybacka - uusmäki
no teoriassahan toi voi pitää paikkansa. ainakin jos koe-eläinten kädet olivat kuivat toisin kuin kiivetessä, kun kädet hikoilee. toisaalta: legenda kertoo myös, että liian kuivat kädet ovat todella liukkaat. kiipeilijät, jotka ovat "katkaisseet hikikanavansa" (tai whatever..) käsistään, joutuvat sylkemään käsiin kitkan lisäämiseksi. näitä tyyppejähän riittää. sangen faschinoivaa...


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 Post subject: Re: Use of 'chalk' in rock climbing: sine qua non or myth?
PostPosted: Tue May 16, 2006 15:05 
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Joined: Tue Apr 11, 2006 16:56
Posts: 50
Tämä oli kyllä mielenkiintoinen tulos:
Quote:
Finally, water had no significant effect on the coefficient of friction.


Ei voi enää sadettakaan pitää tekosyynä reitiltä pakittamiseen.


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 Post subject:
PostPosted: Tue May 16, 2006 15:44 
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Joined: Fri May 10, 2002 02:00
Posts: 1001
Location: Imatra
huh... no mä olen kyl tehnyt hieman testejä just ton saman jutun mukaan ja kieltämättä sisällä kiivetessä puulistoilla ja -sloupeilla hieman (!!!) nihkeenkostee iho on ihan kitkainen. aika sama kuin mankka. kivellä taas... no en kyl kuuna päivänä kupperluijaa käyttäs kivellä vettä kitkoittimena... mut pakko se on uskoa ja jatkossa jää kyl selittelyt märistä reiteistä...


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 Post subject:
PostPosted: Wed May 17, 2006 08:41 
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Joined: Fri Apr 26, 2002 02:00
Posts: 276
Vesi ei ehkä lisääkään käsien liukkautta niin hirveesti, mutta mitens kenkien kumin? Formulat sadekelillä...


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PostPosted: Wed May 17, 2006 09:53 
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Joined: Fri Jun 14, 2002 02:00
Posts: 42
En ihan tuohon tutkimukseen rahojani pistäis.. Tutkien saa sen tuloksen minkä haluaa, kun tollaisella 15 henkilön määrällä tutkii asiata jossa on sata virhelähdettä ja muuttujaa.


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 Post subject:
PostPosted: Wed May 17, 2006 21:34 
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Joined: Fri Feb 14, 2003 02:00
Posts: 301
Location: Espoo
samppa wrote:
no teoriassahan toi voi pitää paikkansa. ainakin jos koe-eläinten kädet olivat kuivat toisin kuin kiivetessä, kun kädet hikoilee. toisaalta: legenda kertoo myös, että liian kuivat kädet ovat todella liukkaat. kiipeilijät, jotka ovat "katkaisseet hikikanavansa" (tai whatever..) käsistään, joutuvat sylkemään käsiin kitkan lisäämiseksi. näitä tyyppejähän riittää. sangen faschinoivaa...


Eihän tuon toteamiseen tarvita kuin kevyt viikon kuuri Antihydralia ilman kiipeilyä. Sen jälkeen sormissa on kellertävät nahkat ja voi pojat - luistoa löytyy :D


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 Post subject:
PostPosted: Mon May 22, 2006 15:00 
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Joined: Sun Jan 20, 2002 02:00
Posts: 84
Location: Nastola
Aivan! Ja löytyy myös syviä halkeamia nivelten taitekohdissa. Mitä tulee käsien kuivaamiseen Antihydral on minun valintani. Vaikuttava aine formaldehydi saattaa aiheuttaa nenän limakalvon syöpää joten nenän kaivamista en suosittele.


Last edited by EVi on Tue May 23, 2006 11:42, edited 1 time in total.

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 Post subject:
PostPosted: Mon May 22, 2006 17:05 
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Joined: Sat Dec 22, 2001 02:00
Posts: 125
...ja jos meinaa pitää ainetta sormissa yön yli suosittelen aika timakkaa kuminauhaa pyjamapöksyihin, jottei purppurapääsoturi kuivaa itseään tarpeettomasti.


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