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Carbon Fins

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Jun 21, 2002
In my videos i always see that top european speros use carbon fins.
Does anybody knows why they are using carbon and not the fiberglass? I guess about few possibility, that time there was not fiberglass fins, or they know how to protect the carbon fins (in rocky area), or they just don't care about it when it broke (economiacally).

Any thoughts?
Top Euro spearos are all sponsored by dive gear manufacturers.

None of the larger brands have other than carbon fins as their top of the line fin product.
Their top divers naturally dive with top of the line gear.

They do not care wheter they break them or not....they are free for them.

Then again on material side...
Carbon fibre (CF) indeed has superior shape memory to fibreglass.
Both actually have very good memory but CF returns to its original shape much faster. Does this mean that all CF blades are superior to fibreglass blades...in most cases just the opposite as the CF blades are made of plain sheets of CF and fibreglass ones are laminated to taper and produce a live and gradually power releasing blade. So as a material CF is ideal (excluding wear resistance) but the outcome is mostly up to the process and the person producing them.

This is an very complex issue and simply looking at the materials will not take one anywhere.

Only safe thing to say is.....plastics are passé.

Did this make any sense at all???

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I bet all of us will vote in favor of carbon fins if we are all sponsored :D "Who cares about kicking the floor?" :D
Yes Mikko thats a good answer. Thats why i saw alberto march kicking all orund the rocks with CF (retail price is 500 dollars here) fins.

But they are other spero who is using CF fins as well like Fabrizio (Italian) and Dapiran (italian also), since those videos were old i guess there was no fiber glass fin few years ago.....

Mikko, since you are producing fins (CF as well for monofin), do you know anyway to make Cf fins unbreakable? Is this breaking problem is due to the material itself, or production process?
Hey Memo, picture this, you are Alberto March and using Omer Carbon Fins. You dive to 45 m and shoot a big grouper. You kick off the bottom and one of your free fins snaps. :(

I think he doesn't want that happening to him down there.

He must have some confidence in the product, same for all other pros using carbon.
Sure he has, If I am Alberto March, I would swap the scratched fins to increase my confidence :D

its for sure that they know how to use the cf fins. At least they should have learned it from the hard way. :)

It is very difficult to produce a CF fin that is resistant to wear and tear. Unbreakable.....never!

CF as a material is very hard and a strand of CF is very tough to break. Problem is that CF is usually used in weaves...and it is essential to make sure that this is not exposed as it may open and start "running".

I can only say that it probably could be done but not at reasonable costs. We are after all talking about dive gear not space ship parts.

We tackled this problem by using kevlar/CF weave instead of pure CF. This is considerably more wear resistant and offers almost identical memory and "snap speed". Also, we decided not to make the fin 100% of this weave as there are parts in the fin where only thing that matters is reliable rigidity (under the pocket). Hence we used the same multifibre that we had used previously in other types of fins with great success.
Also this fin benefits of having a protective laminate added that will positively prevent any scratch from reaching the actual fibres.

So, this fin has a multifibre core, kevlar/CF weave to boost the memory and a protective coating...hence, Hybrid.

Also, this type of construction allows producing the toe angle with relative ease, keeping the price in less than astronomical figures.

The monofin is an different issue, but as it is most certainly less resilient, this material option was reserved for pure freediving equipment only. However, there are further projects sprouting, so stay tuned....

Shaca....you are right......
Problem with CF is not so much the threat of suffering a terminal blade failure..it is more the fact that they start to deteriorate and lose their qualities in heavy use.

OMER carbons are/were actually one of the best designs out there in terms of protecting the CF weave from running. It has some kind of finish on it (urethane??)...and this VERY efficiently keeps them together. Problem is that they tend to start breaking from the tip(split along the length of the blade). Also as they are not laminated to have a tapering profile, they are naturally more solid as the blade is almost as thick from the tip as it is under the pocket. Well.....as far as I understand, OMER carbons are now history and will be followed by BAT family.

Hope that helped??

Good info mikko,

So your hybrids are not fiberglass. Based on your explanation, hybrids are perform like CF fins (since made from Carbonfiber with kevlar protection) with more tear resistance but still not as much durable as kelpie(made from fiber glass) ? But has better snap and memory than kelpie.....

If we assume your hybrid performs same as traditional CF fin, what is the performance advantages over kelpie? by numerical explanations. Like you can gain that much seconds with hybrid over kelpie while diving to 30 meters...

You info also explains why CF speargun are not breakable but on the other hand fins are not....
thats interesting info mikko.
i am curious as what weight and how tight a weave you use for your fins. also, i know UV durability can be a problem, so many people add some kind of mixture to the epoxy resin, do you use this as well?
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Hybrids perform like...well, Hybrids.
There are no 100% CF blades in existence produced with similar method and I'm very reluctatant to compare them to any CF blade currently on the market. Users of Hybrids can comment on this.

I can say that they indeed provide VERY good thrust and "snap".

You have to bear in mind that 50/50 kevlar/CF still has some CF in it and as long as it is in there, it can break.....with kevlar supports this is much less likely and with added protective laminate, even more so.

" But has better snap and memory than kelpie....." Correct!

Numerical explanations can not be given as they vary so greatly from diver to diver. These figures have not been given by any other fin manufacturer as they are 100% sure to cause some very mixed reactions and will be challenged.

Kelpie/BW/Hybrid core is not of fibreglass!!! Only Spearo Line fibreglass blade is the Classic, this one is translucent compared to common yellowish colour usually seen in fibreglass blades.
Others are made of Danish multifibre that is designed for aeronautical and sports applications. It has superior shape memory to fibreglass and with special equipment it can be laminated to an desired angle.

Now, it is much better that their performance will be reviewed by people who use them (other than me) as I can not give you an unbiased opinion. I can only comment their structure details and reasons behind them. Sven has prepared a review which should be out anyday now here in DB and there will be review of these in next issue of HSD.

I'd need to check this from our production manager.
I can yet say that you should use pretty small mesh size as they are more likely to produce uniform flexibility and are less prone to run.....unfortunately smaller the mesh size...more expensive it gets.

The lamination resin used by SpecialFins is not epoxy based.
We tackle this problem by adding one extra protective laminate on top.

We have not noticed any problems with UV durability.
One thing that CF is prone to is excessive heat buildup when left unprotected in direct sunlight. Due to its colur it can heat up pretty rapidly. There are numerous reports from motorcycling world where CF bike parts have been destroyed in sun light.

CF is a great material but comes with several limitations.
So, assuming that CF is always good..................wrong.

In guns CF is a great material as all the gunparts made of CF can be of uniform thickness. No lamination needed. CF is perfect for applications like this. When you need to make the structure tapering, you need to think again.........

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Thats good info mikko. Its a good behaviour not to compare your products with others in public. The sentence that used "assume performs same like Cf fins". This was the result of my logical thinking, i thought if its made from CF with kevlar protection it should perform same. I did not aware of the ratio of the composition and did not intend to force you compare your products with other manufacturers....

Overall i belive this is enjoyable/usefull thread.... If anybody have an idea on this, don't hesistate to comment about it...
I have a friend who was in Italy recently and spoke to the owner of C4 about his fins. He stated that his recent fins are actually very resilient. And that they are much more impact resistant than plastic blades and are approaching that of fibreglass blades, while retaining superior performance characteristics. Much of the hype about carbon blades being fragile seems to be misplaced...at least in c4's case. I have heard about tons of the Sporasub Pure and Variant carbons snapping under normal use, but I have plenty of friends diving the c4's who are abusing them on reef, rock, and wrecks and they have all held up very well. The only breakage I have heard of occured in a boat as the blades were stepped on.

Second-hand accounts aside, I was wondering if any of you have actually snapped a pair of C4's during normal use? If you did, what were the circumstances, and how easy was it to get them replaced under their warranty??? I am just wondering how much of the "carbon fragility hype" stems from, "my friend's , uncle's brother-in law has a friend whose brother cracked a pair of carbon fins.....so on and so forth". I am considering a pair of c4's for my deeper diving/spearfishing, and I am curious what type of experience you guys have had with this.

Originally posted by Mattedhead
I have a friend who was in Italy recently and spoke to the owner of C4 about his fins. He stated that his recent fins are actually very resilient. And that they are much more impact resistant than plastic blades and are approaching that of fibreglass blades, while retaining superior performance characteristics. Much of the hype about carbon blades being fragile seems to be misplaced...at least in c4's case. Thanks-

Hey matt do you have any info/price about those new concept fins????

No...I will ask my buddy though. He was actually talking about the regular c4's although I hear there is a new fin in the works. I'll keep you posted if I get any additional info. Until then, here is an interesting pic--


  • c4.jpg
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I have broken a pair of Sporasub Carbons before, but I have never had a problem with my C4's. I like them so much that I am even thinking about a second pair. Right now I have a pair of 40's, but am thinking about a pair of 30's or 25's. Any recommendations from people who have tried both of those?


I have been thinking hard and reading lots of review on fiberglass, hybrid and carbon models. I made up my mind and will go for C4-Falcon 30's in a few weeks time.
Testing scheduled sometime in April, I'll post feedback.

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if ya want durable carbons, go with C4's. i was over at the technosport/omer warehouse talking with mark and he told me of a little experiment he did. he took 3 types of fins, omer millenium(plastic blades), omer bats(fiberglass blades), and C4 carbons. he then proceeded to smash each fin over the fork on their forklift, in an overhead fashion, the results are as follows. the millenniums busted up (shattered) on the first smash. the bats broke apart, but not as bad as the millenniums, on the first smash. then he smashed the C4's not once but twice without even cracking them. i'd say thats pretty durable. at anyrate, if you want durable carbons, go for C4's.
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