Polyester fleece or fleecing a carbon fiber ski

For discussions related to ski/snowboard construction/design methods and techniques.

Moderators: Head Monkey, kelvin, bigKam, skidesmond, chrismp

Post Reply
poikenz
Posts: 1
Joined: Sun Feb 23, 2020 5:34 pm

Polyester fleece or fleecing a carbon fiber ski

Post by poikenz » Sun Feb 23, 2020 6:00 pm

I've heard mention of putting a thin layer of fiberglass or polyester "fleece" between the core and carbon fiber to promote adhesion and prevent sheering and I was hoping someone could shed some more light on what sort of polyester you have been using, where you get it (if needed) and what results you have had.

I'm new to posting here but I am on my 6th set of skis. my current layup is:

ash veneer, Uni glass, biax carbon, ash core, biax carbon, uni glass.

One issue I have is a constant delamination in a single tip of one ski. I hit jumps on ice, so the tip flexes and sheers under the stress. I don't wish to rivet so I was hoping that I could sand and put a piece of polyester in the tip to improve it's chances of not sheering.

Any thoughts on the subject would be greatly appreciated.

User avatar
chrismp
Posts: 1314
Joined: Fri Feb 13, 2009 9:00 am
Location: Vienna, Austria

Re: Polyester fleece or fleecing a carbon fiber ski

Post by chrismp » Mon Feb 24, 2020 12:37 am

There is indeed some sort of fleece fabric that can be used to improve bonding (we were donated some remnants of this stuff), however I don't have any Information on the manufacturer or the type of material. It is a very thin white non-woven mat, so I guess it could be both fiberglass (most likely c-glass fleece, as most regular glass fleeces are thicker) or polyester. I would prefer fiberglass over polyester in this case as polyester doesn't really form a matrix with epoxy, it just "floats" in there.

Another option might be to use a larger patch of VDS rubber as a bonding agent and shear layer.

SleepingAwake
Posts: 139
Joined: Mon Oct 11, 2010 11:06 pm

Re: Polyester fleece or fleecing a carbon fiber ski

Post by SleepingAwake » Mon Feb 24, 2020 1:03 pm

My local supplier has a 30gsm glass veil that works well, but it really shouldn't make much of a difference what exactly you use as long as it has a decent bond with epoxy and will form a resin rich bond line.

K2skier
Posts: 1
Joined: Tue Feb 25, 2020 9:20 pm

Re: Polyester fleece or fleecing a carbon fiber ski

Post by K2skier » Tue Feb 25, 2020 9:26 pm

So does the "fleece" create a host for a thicker resin layer? Is that the point? Just wanting to understand why it helps... :idea:

User avatar
chrismp
Posts: 1314
Joined: Fri Feb 13, 2009 9:00 am
Location: Vienna, Austria

Re: Polyester fleece or fleecing a carbon fiber ski

Post by chrismp » Fri Feb 28, 2020 12:21 am

Yes, the point is to keep a certain amount of resin between two layers of different materials where one material might absorb too much resin from the bond line between the two layers.

Post Reply