Scaling Construction and Dimensions in Ski Design

Philpug

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This thread is for the general discussion of the Article Scaling Construction and Dimensions in Ski Design. Please add to the discussion.
 
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pchewn

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If the goal is to make the same sized turns on each length of ski, then yes, something else must be scaled to make that happen.

Which brings up another point: Why market the skis by waist width models? Why not market them by the optimal turn radius?
 
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If the goal is to make the same sized turns on each length of ski, then yes, something else must be scaled to make that happen.

Which brings up another point: Why market the skis by waist width models? Why not market them by the optimal turn radius?
If someone is looking for a soft snow biased ski, are they more concerned if the ski is 98mm underfoot or has a 17.8m radius?
 

Ron

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its not just TR, its also the energy required to bend the ski which is really what makes a ski turn. true turn radius is actually pretty theoretical given that each skier weight is different as are the forces applied. We can say a ski has X radius based on a mathematical formula but physics will say differently. Float, stiffness (vertical and horizontal ) contact points on hard or 3-d snow and other factors will greatly affect how that ski actually performs
 

Bad Bob

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To maintain the same characteristics wouldn't you have to play with the lateral rigidity of the ski as well? Unless you want to build an ice skate this would have to be a factor.
So, you would have to adjust:
Flex
points of stiffness (very few skis have a totally even stiffness tip to tail)
lateral rigidity
side cut
width
Turn radius
weight
and probably a dozen other things

When it is all over each length would ski differently based on the skiers weight and height.

This get complicated.
 
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To maintain the same characteristics wouldn't you have to play with the lateral rigidity of the ski as well? Unless you want to build an ice skate this would have to be a factor.
So, you would have to adjust:
Flex
points of stiffness (very few skis have a totally even stiffness tip to tail)
lateral rigidity
side cut
width
Turn radius
weight
and probably a dozen other things

When it is all over each length would ski differently based on the skiers weight and height.

This get complicated.
Absolutely it does, Volkl's Tailored Tital Frame addresses a lot of that.
 

bbbradley

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If the goal is to make the same sized turns on each length of ski, then yes, something else must be scaled to make that happen.

Which brings up another point: Why market the skis by waist width models? Why not market them by the optimal turn radius?
What exactly is "optimal turn radius?" It sounds like a subjective term, while the measurements are the measurements. I can take a 30m ski and with a copious deployment of edge angle make a smaller radius turn, the ski still measures/calculates at 30m.

From my limited knowledge of it, ski design, geometry, and construction is an art and science...complicated by the person attached to the ski.
 
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Yes, it is complicated. Which is why I think it is wrong to market skis with a single identifier (width) as the most indicative of the skis character.
I agree, otherwise you are limiting yourself and confusing the consumer. I think Sheeva 9, 10 and 11 is better than the Black Pearl 82, 88 and 97. Or with Head V6, V8 or V10 vs. Kore 87, 93, 99, 103... when only one of the models is that width in the latter example.
 
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bbbradley

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I agree, otherwise you are limiting yourself and confusing the consumer. I think Sheeva 9, 10 and 11 is better thant the Black Pearl 82, 88 and 97. Or with Head V6, V8 or V10 vs. Kore 87, 93, 99, 103... when only one of the models is that width in hte latter example.
Counter is that the mfg is making assumptions about what the consumer knows/interprets about the ski based on an arbitrary number.
  • High/Medium,/Low are interesting but can't be compared between brands
  • Raw data is interesting but can be confusing or overwhelming
Both describe the same ski:
"ski intended for high level racers"
"ski is 165 cm and measures 118/65/104"

*edit*
The mfrs don't help themselves when in the same ski, but different size (157) they use this:
"ski designed for elite-level athletes"
 

James

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I agree, otherwise you are limiting yourself and confusing the consumer. I think Sheeva 9, 10 and 11 is better thant the Black Pearl 82, 88 and 97. Or with Head V6, V8 or V10 vs. Kore 87, 93, 99, 103... when only one of the models is that width in hte latter example.
Why not just call it the Kore __ where blank is the actual waist width.
The confusion comes when a Kore 93 is only 88, in shorter sizes, and is so marked. I guess the Kore 87 would really be 82 in that size.
So, maybe I agree that where your scaling don’t use the waist with in the name unless it’s only 2-3 mm difference. Three tops.
 

bbbradley

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We have concluded that the metric system is an arbitrary unit of measurement in the ski industry.
Ahhh, but it is not, it is a standardized unit of measurement. 1cm = 1cm.

"It was decided that the new system would be based on a natural physical unit to ensure immutability. The academy settled on the length of 1/10,000,000 of a quadrant of a great circle of Earth, measured around the poles of the meridian passing through Paris. An arduous six-year survey led by such luminaries as Jean Delambre, Jacques-Dominique Cassini, Pierre Mechain, Adrien-Marie Legendre, and others to determine the arc of the meridian from Barcelona, Spain, to Dunkirk, France, eventually yielded a value of 39.37008 inches for the new unit to be called the metre, from Greek metron, meaning “measure.”
 

bbbradley

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Totally arbitrary.
Wide/medium/narrow is 100% arbitrary and impossible to define.

"defined as one ten-millionth of the shortest distance from the North Pole to the equator..." Better? It is standardized, which is far better than wide/medium/narrow. :P

You have to start somewhere and get an agreement for this measurement thing to work.
 

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An arduous six-year survey led by such luminaries as Jean Delambre, Jacques-Dominique Cassini, Pierre Mechain, Adrien-Marie Legendre, and others to determine the arc of the meridian from Barcelona, Spain, to Dunkirk, France, eventually yielded a value of 39.37008 inches for the new unit to be called the metre, from Greek metron, meaning “measure.”

Totally arbitrary.
The French- what have they ever done for us???

 

tromano

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Aren't there a few skis that do not measure in accordance with their reported sized either? Numbers are hard.
 
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