Critique please and questions - I want to get laid properly

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Gilo
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Joined: Sun Feb 03, 2013 7:36 am
Location: Somerset - the flatlands

Critique please and questions - I want to get laid properly

Post by Gilo »

I am in the design phase of building my first pair of skis - I have built boards before and I have posted some pics in the log section if you want to look

I want to build a pair of AM skis.

Dims are going to be 122 99 111. Early rise nose and slightly rockered tail.
Probably 10mm of camber under foot.

The core will be made of poplar and ash with ash sidewalls. core dims are going to be 2mm - 11mm - 2mm. I intend to put a 50mm flat spot under the boot centre point.

Question 1.

At what point on the core do I start the transition from the 2mm tip up to the 11mm point? this applies to the tail also. I know that each ski has a different profiled core but a general rule where should I start?

The lay up will be thus:

15.5oz biax
3.5oz UD CF (full width)
Core (11mm)
3.5oz UD CF (full width)
15.5oz biax
fabric
Topsheet

Question 2

is this a sensible lay up?

Question 3

Would it be possible to swap the positions of the CF and FG around in the lay up so that the top of the ski would show the CF. I would then dispense with the fabric and just put the top sheet on top of the CF? It's a cosmetic thing!

Thanks in advance for your views - they really are very helpful to a ski build virgin

Gilo
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MontuckyMadman
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Joined: Fri Jun 20, 2008 9:41 pm

Post by MontuckyMadman »

10cm
Yes
yes
Idris
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Post by Idris »

1. without seeing a diagram of you'r skis I'm guessing - but based on what I build go for 20cm back form the tip and 10cm in from the tail.
If you realy want to go for a flat bit, go for ball of foot, not boot center. This should also bee your cores thickest point.

2. If you've built boards before then you should be able to answer this...but if you've not played with these materials before and these are your first skis I would just go for 22oz triax glass top and bottom, and no or plain topsheet - get some experience in seeing what works , then experiment.

3. See 2. But should make no decernable difference
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twizzstyle
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Location: Kenmore, Wa USA

Post by twizzstyle »

There is no rule of thumb with profiles, everyone has their own favorite profile, and small changes can make big differences, especially near the tips. My profiles are not linear, they have a smooth curvy transition so my tips are fairly soft, with fairly stiff waists (if that makes sense).

I've never done anything other than 20oz triax fiberglass with uni carbon added, so I can't help with the materials. Seems reasonable.

If you flip the CF to the top, you may as well flip it on the bottom (so the CF is the bottom-most layer). That will reduce the likelihood of camber changes (won't eliminate it, but may help)
Dtrain
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Location: Prince Rupert/Terrace B.C.

Post by Dtrain »

15.5 biax carbon is too heavy. The worn even flex torsionaly. Some peoples idea of a great carving ski, but not all. Those are not pinner dims your planning for this ski. You go heavier on the uni and thin the core out a bit more?
Dtrain
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Joined: Wed May 18, 2011 12:03 pm
Location: Prince Rupert/Terrace B.C.

Post by Dtrain »

I lied....99mm underfoot. Toothpick
Gilo
Posts: 62
Joined: Sun Feb 03, 2013 7:36 am
Location: Somerset - the flatlands

Post by Gilo »

Thanks for the input guys - I'll keep you posted.

Gilo
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