Necky Carbon Layup

guessing it’s mostly theoretical
I think the amount of each material has more bearing than on where it’s located with regards to resisting the forces that would fracture the laminate. I could see the rational that reducing point impact on the carbon by putting it behind kevlar/glass would reduce the peak loading that could take the carbon to failure but honestly that’s such a high loading anyway. There’s a neat book out there about whitewater composite kayaks and various tested laminates. The optimal glass/kevlar ones had the high compressive strength s-glass on the outside with the high tensile strength kevlar on the inside. That would lead me to believe carbon/glass on the outside with kevlar on the inside would make sense. But I’m wondering if seperate laminates of carbon/kevlar make sense as opposed to carbon/kevlar weave cloth on the inside with core materials and s-glass on the outside.

What does the Onno/Tideline (forgot your name) fellow say?

QCC boats do not usually endure the
sharp, deep blows to the hull experienced by whitewater boats. For whitewater boats, the outside layer is usually S-glass, sometimes a composite of Kevlar and carbon, occasionally pure carbon. If carbon is the inside layer on a whitewater boat, and if the hull is flexible, then the inside carbon is going to split.

I bought a used slalom c-1 from an Olympic paddler which had S-glass outside, carbon inside. It is extremely stiff, and just hasn’t ever deformed inward enough to split the carbon. But at the time ('96), the boats were considered virtual throwaways, and on the Olympic course, they were unlikely to strike rocks. I am a careful paddler, so I haven’t had problems, but if I had ordered the boat “new,” I would have asked for S-glass outside and Kevlar inside.