Vinylester & Carbon

[idkfa]

Both Columbia Yachts and McConaghy have new VE-carbon boats.

Surely they are not using csm between the layers???

I've seen this done with fibreglass, is this "normal"?

Should one think of VE more like PE or Epoxy? Is it an adhesive or just bonds well to itself? Or it depends on the VE?

[Eric Sponberg]

Idkfa,

There are a few different kinds of vinylester, some based on epoxy formulations, other based more on polyester formulations. Both types use styrene as the monomer in the chemical reaction when it cures, VE much more so than PE. That's part of what makes VE so sticky and impervious to liquids, like water, passing through it. VE, besides being more sticky, is also just not very porous. To use it with carbon fiber is not unheard of, and care should be taken to assure that the carbon fiber is "sized" (i.e. coated) properly so that the resin will stick to it. All composite fabrics are sized with a sizing material, and most carbon fiber is sized to be compatible with epoxy resins. So you get the best marriage of VE and carbon fiber is the VE is one that is based on epoxy chemistry.

No, I very much doubt that there would be mat between the layers of carbon fiber.

Eric

[Herman]

If shrinkage of the VE is limited, (it usually is) there is no real need for CSM, especially if multiaxials or UDs are used, which do not generate large resin rich spots. With infusion you are even better, as resin rich spots are even more prevented.

Also see this PDF file, which has some info on different sizings.

My supplier for carbon multiaxials (http://www.multiaxialfabricselcom.com/) stocks a type suitable for polyester, and a type suitable for epoxy. VE is on request.

[idkfa]

Thanks guys, considering this for it is compatible with gel-coat in a mould.

[tunnels]

For just plain hand laminating using fabfrics i always use a 225 gram csm between to help tie the just resin layer between the layers . even with a good quality Vinylester !! This helps when it comes to shear and have never been able ever to simply peel layers when csm is used . Peelablity is a good test of resin strength
Its amazing how easy some resins are able to simply peel the layers of fabrics of just glass without any csm between ,its down right scarey infact!!.

[Herman]

Using fabrics and hand laminating, yes. Using multiaxials and infusion, no.

Many multiaxial producers offer their multiaxial with 150 gr.m2 CSM for hand laminating with low shrink resins.