absolute definitive answer for the hard of thinking - me!

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Gilo
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absolute definitive answer for the hard of thinking - me!

Post by Gilo »

Before anyone says "do a search" I have but am still unsure about the answer to this question, so please bear with me......as I said hard of thinking.

So here goes:

If we take an all mountain ski as the example - 132-100 124

Core 2-12-2

when I design the ski I centre the middle of the sidecut and the max thickness of the core with each other.

1. How do decide where that point is on the ski in relation to the true centre (ie the 90 cm mark)?
2. where should that thickeness/sidecut midpoint be in relation to the boot?

I have got rather confused about this.

Thanks

G
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Akiwi
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Post by Akiwi »

Thanks for the question Gilo, I am currently designing a similar ski and had exactly the same question.
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pmg
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Post by pmg »

I always have all 3 centres aligned. So foot centre = sidecut centre = thickness centre.
And that's where I start designing from. So I do not think "My ski is 180cm long, where should I put the sidecut centre in there?" But "My ski centre is 98mm wide, 180cm long, I would like my tip to be 12mm wider than the tail, so lets look how long the forward and backward section get."
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vinman
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Post by vinman »

When I draw up a new ski I take the length and divide by something in the range of .53-.55 (53-55% back when measured from the tip.) depending on what type of ski it might be. If I want a ski that will initiate a little easier I place the waist closer to 53% from the tip. If the ski is meant to be a more surfy powder ski I'll place the waist back just a little more.

Some of this depends on what the purpose of the ski is and to some extent what looks right when I begin drawing. Some of this might depend on how if the ski is rocketed in the tip or tip and tail and if there is any reverse side cut in the tip.

The When I profile my cores I place this mark at the thickest part of the core.

When I press the ski this spot will also be at the highest spot of the camber.

So essentially I do the same as PMG but I do think about where the true waist of the ski will be before I start building anything.
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pmg
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Post by pmg »

Well, I also dras before I build anything :) If the full-size drawing on the wood the template will be made of looks right, I start working.
twizzstyle
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Post by twizzstyle »

If you use a circular sidecut, and pick your three widths, the center location is chosen for you. Alternatively, you can choose two of the widths, and the location of the waist (minimum width), and the third width will fall out.

I, too, try to put my max thickness, sidecut waist, and boot center all at the same location. If your profile center is further forward, it will feel like you have VERY soft noodly tails.
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falls
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Post by falls »

I usually put boot centre, thickest point and sidecut centre 6.5cm behind true centre of the ski (true centre being half the length of the ski AFTER it has been moulded). This puts the ball of my foot (mondo 27.5 boot, 318mm BSL) on the true centre point.
Often I have a flat thickest area under foot then taper after the binding screw mounting points. Other times just a curved profile with thickest point at boot centre.
Highest point of camber is sometimes a bit variable with the way I generate the camber with heat, but it is under the boot in all cases.
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