13 SKIS Building proces

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dvollebregt
Posts: 23
Joined: Fri Jul 26, 2013 2:27 am

Post by dvollebregt » Wed Oct 04, 2017 9:05 am

So you suggest:

Flax 350
UD carbon
BCore
UD carbon
Flax 350

skidesmond
Posts: 2318
Joined: Tue Apr 07, 2009 3:26 pm
Location: Western Mass, USA
Contact:

Post by skidesmond » Wed Oct 04, 2017 1:14 pm

Yes, that how I do it.

SleepingAwake
Posts: 133
Joined: Mon Oct 11, 2010 11:06 pm

Post by SleepingAwake » Thu Oct 05, 2017 1:22 am

I strongly disagree with that and I know of a few cases where this lead to problems. You generally try to have a smooth transition in stiffness in order to avoid shear stress on the interface. So always core to biax to UD.

If you want to have the UD against the core I would recommend putting a very light glass or polyester fleece in-between core and UD to give it a little bit of a tougher interface.

Furthermore you would want to change the core profile as well when you switch around layers like that.

gav wa
Posts: 375
Joined: Tue Feb 18, 2014 8:58 pm
Location: Perth

Post by gav wa » Thu Oct 05, 2017 5:31 am

SleepingAwake wrote:I strongly disagree with that and I know of a few cases where this lead to problems. You generally try to have a smooth transition in stiffness in order to avoid shear stress on the interface. So always core to biax to UD.

If you want to have the UD against the core I would recommend putting a very light glass or polyester fleece in-between core and UD to give it a little bit of a tougher interface.

Furthermore you would want to change the core profile as well when you switch around layers like that.
Do you think this applies to triax glass as well?
So don't have the 0 degree fibre against the core?
Wouldn't there always be a big differential against the UD layer?

SleepingAwake
Posts: 133
Joined: Mon Oct 11, 2010 11:06 pm

Post by SleepingAwake » Thu Oct 05, 2017 7:55 am

gav wa wrote:
SleepingAwake wrote:I strongly disagree with that and I know of a few cases where this lead to problems. You generally try to have a smooth transition in stiffness in order to avoid shear stress on the interface. So always core to biax to UD.

If you want to have the UD against the core I would recommend putting a very light glass or polyester fleece in-between core and UD to give it a little bit of a tougher interface.

Furthermore you would want to change the core profile as well when you switch around layers like that.
Do you think this applies to triax glass as well?
So don't have the 0 degree fibre against the core?
Wouldn't there always be a big differential against the UD layer?
In theory this applies to fiberglass as well, but as your average carbon fiber is around 3 times stiffer than glass fiber the problem is less pronounced.

gav wa
Posts: 375
Joined: Tue Feb 18, 2014 8:58 pm
Location: Perth

Post by gav wa » Fri Oct 06, 2017 7:47 am

Thanks for the info. I have been planning to make a set of foldable approach skis that aren't heavy and unreliable like mtn approach. I have some carbon ready to go but now i might add a bit of light glass between the core and carbon.
Cheers bro.

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