Fins split or paddles??

[bradshsi]

But, then this begs another question, which foot get's which fin?

I guess the answer to that is that you put the faster fin on the left foot if you want to turn right and vice versa

Careful with you ultimate answers Quarrior, you might start a new fashion trend...

 

[Charlie99]

What I was pointing out in my previous post, was that to claim "Split fins are no good in current.", is a wild illogical oversimplification.

The fact remains that current has no influence on the fin performance. In the end if you pick the fin that gives you the best speed performance, you will have the fin that performs best in a current.

And to say that current has no influence on fin performance is a mild oversimplification. Yes, finning at 2 kts in still water, or staying in one spot above ground in a 2kt current is equivalent. But what happens in real life is that a diver gets into a 3kt current and start kicking harder and wider rather than faster. The splits just don't respond to big powerful kicks as one would expect. If the diver isn't used to splits, or doesn't have the discipline to keep finning away with a small amplitude flutter but faster and faster rate, then that diver is going to not increase his speed like he wants.

Twin Jets and Apollo BioFins are awesome fins. On my first dives with splits, my buddy had to repeatedly motion for me to slow down. Only by looking at the bottom go zooming by did I realize how fast the fins were pushing me for how little effort I was putting into finning. Very efficient, very easy to use, but they require some skill to get the very best performance/highest speed.

My experience with splits matches Mambo Dave's ----

Split fins are faster, granted, but it seems to me that the already fast kick needed for splits can't be sped up much more to counter currents. They can't be loaded, i.e. kicked with force, as their design flops over on itself like a wet noodle. Similarly, big kicks didn't seem effective during my test of them.

 

[tjmills]

And to say that current has no influence on fin performance is a mild oversimplification. Yes, finning at 2 kts in still water, or staying in one spot above ground in a 2kt current is equivalent. But what happens in real life is that a diver gets into a 3kt current and start kicking harder and wider rather than faster. The splits just don't respond to big powerful kicks as one would expect. If the diver isn't used to splits, or doesn't have the discipline to keep finning away with a small amplitude flutter but faster and faster rate, then that diver is going to not increase his speed like he wants.

Twin Jets and Apollo BioFins are awesome fins. Very efficient, very easy to use, but they require some skill to get the very best performance/highest speed.

My experience with splits matches Mambo Dave's ----

Man, I know that it feels that way but I have to tell you that the results don't hold up that way. They feel flimsy and it doesn't seem like you are getting much out of them until you look down at the bottom going by. Every piece of evidence that studied the results and reviewed the products certainly don't support your threory here. Not one.

I do know what you mean by FEELING and its actually hard to let yourself get used to kicking that easy but it really does work with much less effort which does equal much less air consumption. Now granted, I am not diving with doubles and triple redunency HOG rig and a dry suit with an anvil tied off to my weight belt but I can't believe the results would be any different.

Quite frankly I didn't believe all the hype and marketing either but after using them last week in Bonaire I did find they were much more powerful and easier to dive with. I haven't mastered all of the kicks with them yet but I will be selling my Quattros now. I do agree, at least at this point, that precision control isn't easy with them so some activities like penetration and precise photography might be better with jets or others but than again....nothing is better than excellent buoyancy skills anyway.

 

[bradshsi]

Yes, finning at 2 kts in still water, or staying in one spot above ground in a 2kt current is equivalent. But what happens in real life is that a diver gets into a 3kt current and start kicking harder and wider rather than faster. The splits just don't respond to big powerful kicks as one would expect. If the diver isn't used to splits, or doesn't have the discipline to keep finning away with a small amplitude flutter but faster and faster rate, then that diver is going to not increase his speed like he wants.

That sounds like a good explanation to me and agrees with my own (limited) experience. Although it might be semantics, I would say that your observation shows that while the fin's performance is unaffected by the current, the diver's is not

Interestingly, testing by Grier seemed to show that small amplitude rapid kicks were better for both split and paddle fins (at least for flutter kicking). See the link below for a full discussion on this.

http://dive.scubadiving.com/members/gearreviews.php?s=502

 

[Charlie99]

Man, I know that it feels that way but I have to tell you that the results don't hold up that way. They feel flimsy and it doesn't seem like you are getting much out of them until you look down at the bottom going by. .....

Quite frankly I didn't believe all the hype and marketing either but after using them last week in Bonaire I did find they were much more powerful and easier to dive with.

My intial response was similar to your and Bradshi's ---- finning into a current isn't any different than finning high speed in still water. OTOH, there are many people that report problems in currents. Too many to discount as just an oddball case of someone who has some ulterior motive for bashing split fins.

With split fins (specifcally Apollo Bio-Fins) I get great speed with amazingly little effort in normal conditions. But if I use big, powerful kicks, then the splits don't work so well. My guess is that the "don't work in currents" reports are from people that got excited, tried to fin hard and big rather than fast, and the splits didn't perform well.

I dive with lots of people that use them and swear by them. They are diving on reefs, and while they may do a helicopter turn here and there, they don't have any real need to fin backwards. Great fins for what they do.

My post simply puts forth a hypothesis about why there can be such radically different opinions about split fins from well intentioned divers.

 

[claplant]

One thing that I really like about my appolo is that they are great while diving, but I think that they are even greater when snorkeling.

 

[O'Malley]

I have only ever dove splits, SP Twin Jets, and gotta say...I love 'em. But this year, I have gone dry and opted for paddles, SP Jet Fins.

 

[Sasquatch]

Started years ago with paddle fins and had few complaints. Switched to TUSA Zoom splits and really like them. Just last week practiced fin turns and reversing, they performed very well indeed.

Sea ya!

 

[Dive-aholic]

Is there some analogy between split fins' performance, speed and in current, and sport bikes? Please bear with me here as I explore this line of thinking out: Sport bikes are arguably some of the fastest vehicles on our roads, but just because they can do 170 miles per hour, does that automatically mean they'll pull a 5000 lb. trailer better than my truck?
My last truck only had 120 hp from the factory, but it was a 300 cubic inch six cylinder. Its peak torque was at 2000 RPM, and it had a good amount of it. My last sport bike came close to the hp rating of my truck, but it still wasn't meant for hauling. (The old engine adage 'There is no replacement for displacement' may apply here, but I'm still not sure)

Split fins are faster, granted, but it seems to me that the already fast kick needed for splits can't be sped up much more to counter currents. They can't be loaded, i.e. kicked with force, as their design flops over on itself like a wet noodle. Similarly, big kicks didn't seem effective during my test of them.

A paddle may not be as fast, but they can be powered, if need be, to effectively displace more water per kick in a load situation than a split (which is seemingly at its limit for normal waters). What i am claiming is that me way be looking at the displacement of water when the going gets rough. It seems to me that a large paddle would, by default, move more water, albeit slower, than a split fin. (So I guess this means a split fin aims it's lower water displacement better to use as thrust?)

In engine terms, an effective paddle (I'm thinking Jet fins here) can produce more usable torque, while a split fin may have more horsepower.

What fire hose is going to be tougher to hold steady - a small hose pushing forth a good amount of pressure, or a large hose at a moderate pressure?

I'm not claiming that I have the answer here, but I'd like some of ya to consider analogies to the split vs. paddle in current debate, as I am just as curious. In fact, I'm dead set on buying a set of split fins - probably Apollos at this point.

Personally, I'd like to test out multiple fins in an endless pool (the pools that keep water flowing). http://www.endlesspools.com/index.html

Best,

Dave

Brad, do we have another honorary engineer???

 

[Dive-aholic]

Ok, here's the final and all encompassing answer.

Use one of each.

But, then this begs another question, which foot get's which fin?

Brilliant!!! If I only hadn't sold my old splits. That's okay. I'm going on a camping/diving trip next weekend. I will borrow a split and go diving. I'll find some current too. I'll be able to determine which works better by which way I turn as I fin. The hard part will be doing the flutter with the split foot while I do the frog with the paddle foot!!!