what's better kevlar or carbon for surf ski

i currently have Fenn Swordfish Vac-Glass was thinking of upgrading to Kevlar or even Carbon for the added lightness . besides being lighter is it better for strength i dont really go into areas that going to smash the ski or waves. just knowing its stronger it gives me a bit more security on the water. any advice would be great.

thanks in advance

How much material & how it's layed up (direction of layers, thickness of each layer, amount of resin, etc) probably has far more effect than what the material is. Also strength can mean amount of rigidity or flexibility, or puncture resistance, etc. This topic won't have a simple answer.

Ditto on the challange of a definitive answer to the question. Of note is the "trend" towards "hybrid" layups using various combos of material. Also important are coring materials and layup tech ( pre-peg , vacuum infusion ,etc. ) . My Hybrid Huki S1-XL (carbon cockpit and strategic carbon placement else where) is pre-pegged vacuum bagged epoxy resin w?a proprietary core material came out stiff and strong at 25 pounds.

All this is true and simplification doesn't necessarily give good answers. But for want of a simple answer...

Carbon is better.

Think of the typical uses for each of the fibres. Kevlar is used in flack jackets. Carbon in structural components of formula 1 cars. The fibres in Kevlar resist parting more than the other fibres so are much better for (not) being spiked. So maybe a better choice for flatwater racing over fence star pickets and the like.

Carbon will hold more tensile force and should be more rigid than glass or kevlar. All other things being equal carbon will flex less and the ski will hold it's shape better.

As mentioned, the start for lighter but no impact to strength is pre-peg and vacuum techniques. Glass can be fabulous and quite light in this case. And sometimes racing versions of carbon skis have chased weight reduction so excessively they can have strength problems. This isn't the fault of the fibre.

I've always thought that carbon was used for its light weight and stiffness and Kevlar for its toughness like for skis that will take a beating in shallow rivers, etc. where carbon would be a disaster, on the bottom of the ski at least. I've never heard of a 100% Kevlar ski as I think it would be too heavy but it would have tremendous impact resistance. When Kevlar is used I believe it is usually used in combination with carbon whereas some skis are 100% carbon where lightweight and stiffness are the most important factors.

That's my $0.02 and that's about what it's worth.

This should answer some questions.

www.christinedemerchant.com/carbon-kevlar-glass-comparison.html

"Kevlar layups will flex more than carbon designs of the same weight. Kevlar is strong under tension but weak in compression" is me just parroting lore I have heard and read, but it jibes with my experience owning boats with carbon, kevlar, and blended weave fabric.

But I will say one thing with 100% confidence - it is much harder for me to repair kevlar than carbon.