Carbon kevlar fins

This may be new to some of you or not so new to others, carbon kevlar is a material that can be used to make fins. Some manufacturers are experimenting with kevlar and it may be the next trend. It is said that the carbon kevlar material is superior to carbon as far as strength and durability but is just as light. These are the carbon kevlar fins we are now sampling. The format (length, width and shape) is the same as our carbon blades. I used a digital scale to weigh the blades, the CK is 314g vs the carbon at 304, only 10g heavier. I don't think I'd be able to feel 10g if it was put in my hand. To talk about durability I don't know what I'd have to do to the blade to test it. You've seen me drive over the carbon blade, I'm sure the CK blade will take it no problem.

Looking at the pics you will see that surface of the blade has a checkered pattern. What you're seeing is the carbon interweaving with the kevlar. The carbon is black and the kevlar is light green. Kevlar can be made in a variety of colors which will allow for very interesting product differentiation from a manufacturers stand point. These blades are just samples that were not made to our specs, so I can't make a final call on the qualities of the blade. If we were to go with it we would use this material instead.

All in all kevlar presents some very interesting possibilities for application in fins.

Cost will be the same as carbon blades.

Have you ever had a fin fail completely? If so how?

When we're talking about durability and strength it would be helpful to define the point at which we consider the blade to have failed. Obviously if it breaks in half or breaks along the screw holes line it would be considered a complete failure. A strong hit perpendicular the front edge of the blade will likely chip all blades. Cosmetic scratches will happen immediately when reef bottom hunting. So what kind of durability are we looking for exactly?

With the carbon blades for example I believe no kicking effort in open water will break the blades. I also believe no impact such as jumping into the water off the boat will break them. Weight being thrown on top of them will also not break them unless the blade was placed on it's side edge. What can we do underwater to make the blade fail? Push off the bottom possibly? I would like to devise a test with input from you guys and am willing to put a pair of carbon blades and a pair of kevlar blades through it.

I used the carbon kevlar blades on one outing which was enough to give me a good idea of how they perform. We covered depths from 30ft to 60ft and did some moderate surface swimming. The blades did their job well without making me tired at all and no ankle or knee pain. I found them to be not as fast as the carbons, meaning the blades don't snap back into straight as fast as the carbons. This factor is apparent to me after how many fins I've been experimenting with lately. The carbon kevlar blades are comparable to good fiberglass blades, but are a little lighter. The durability factor I have not been able to ascertain because that takes a long time.

In conclusion I'll continue using the Speardiver carbon fins I found nothing better and doubt that there is. The pretty colors available with Kevlar is not enough of an incentive. In theory Kevlar is a material that's good at dissipating energy, think Kevlar bulletproof vest, not ideal for fins where you need the energy back as efficiently as possible.