Ski dimensions

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Gilo
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Ski dimensions

Post by Gilo »

I've just posted over on the journal board some pics of 3 recent builds.

2 of the skis have the dimensions 181cm long, 140-100-121. The tip dimension of 140 worries me as I was aiming for something a bit less than that. I must have made a mistake when I was cutting out templates etc.

To the eye it looks okay but it is big

Does anyone have a view about this and what are the potential dangers of such a wide shovel?

thanks

Gilo
Gilo
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Post by Gilo »

Hello folks

I want to bump this one to the top again to see if I can provoke an answer

What is the relationship between nose width (in this case 140) and tail width (120)?

I am worried that the disparity is too extreme

Does anyone have a view/experience

Giles
skidesmond
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Post by skidesmond »

There's no perfect ratio or formula to follow that I've found. Look at the manufactures... I looked at a number of ski dims over the last couple years and the tail is generally 85%-90% less than the tip. Most of my skis I make fall into that range.

IMO 140 tip is pretty wide. Are these for big powder days?
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vinman
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Post by vinman »

20mm of taper is a lot but not totally out of the ball park on a big powder ski. This will allow the tail to sink more in relation to the tip. Go for it. Put a waist of 110-115 on it and you'll have a sweet deep pow slayer.
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Gilo
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Post by Gilo »

The skis are already made 140-100-122

I didn't mean for the tip to be that wide - I had 135 as my target but somehow cocked it up.

The ski is not really designed as a powder slayer - think Rossignol TI100. All mountain, do anything Subaru Impreza group 1 rally ski - crud and chop eater, groomer charger.

In surfing terms not a full on 9ft gun, but more a 7ft step up to give a bit more confidence and get you in earlier.

G
sammer
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Post by sammer »

Gilo wrote:The skis are already made 140-100-122

I didn't mean for the tip to be that wide - I had 135 as my target but somehow cocked it up.

G
I'm guessing you forgot to factor in the fact that edges are gonna add ~4mm to your overall width.

sam
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MadRussian
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Post by MadRussian »

Gilo wrote:The skis are already made 140-100-122

I didn't mean for the tip to be that wide - I had 135 as my target but somehow cocked it up.


G
if your plants was 135 and you got 140 it's no big deal only 5mm.
Probably you got rocker and sidecut radius continued into the tip make it wider.
In form of dimensions Salomon BBR come to mind. those have even more radical dimensions 145 – 88 – XX.

Ski season just around the corner 8) you'll find out in a short few weeks I suppose lol

personally wide skis with 140 tip I would do 110 – 120 waist
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vinman
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Post by vinman »

What Sam said. Edges are 2.2 mm wide, probably accounts for your extra width.
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pmg
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Post by pmg »

What radius do the skis have? sounds like something around 15-16 meters. In my opinion a bit small for a wider ski.
Gilo
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Post by Gilo »

According to the plan on boardcrafter the radius come out a 21m

Ski season coming up so we shall see!

G
pmg
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Post by pmg »

Just ran a calculation, a ski with 21m radius and 100mm underfoot has a width of 140mm 916mm away from the ski middle, and a width of 121mm 664mm away from the ski middle... So if your tip and tail are very race-like, the 21m could fit :) Well, winter is coming, I hope the skis come out nice and, more importantly, you have a lot of fun on them!
Gilo
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Post by Gilo »

Morning everyone - PMG, I've just measured my skis. All measurements are from the base

The ski is 180, therefore centre is @ 900mm. From that point to the widest point of the tail is 813mm and to the widest point of the nose 720mm.

The true centre of the ski (narrowest and thickest part of the core) is at 855 from the tail. From that point to the tail wide point is 760mm and from that point to the nose widepoint is 775mm.

How does this look when you plug those numbers into your box of tricks.

Obviously the proof of the pudding is in the skiing and they don't loo mis-proportioned, albeit being wide in the nose. If you want to look at pics of them go to the journal section and they are there under my "Summer Harvest" post.

Cheers

Gilo
pmg
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Post by pmg »

Hi Gilo,

with Ski middle I always mean the narrowest part where the middle of the ski boot usually is. => you call it true centre.

As the distances from the true centre to the widest point on tip and tail are nearly the same, your Ski obviously has a narrower radius towards the tip. Thats what a lot of Ski manufacturers do, like this the ski helps turning more but gets more nervous at high speed.

Just asked my little helper, telling me that 40mm difference on 775mm is roughly a 15m radius, while 21mm difference on 760mm is roughly a 27m radius.
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