Split fin versus the blade

[terson]

Hi Guys,
I always hate it when the guy in front swims off and leaves a cloud of sand in place of the critters that I'm looking to photograph.
I really hated it until I saw a video of myself under water and was completely embarrassed when I saw a cloud of sand rise up behind me when I moved from one subject to the next.
After watching the video carefully, it was obvious that the split fins were sucking up the sand into the water column when I started finning.
I'm now wondering if there is any documented proof that a blade fin is any better at NOT kicking up sand than a quality split fin?
Note that I said "documented" proof, not wive's tails. I'm looking at buying new fins to try and alleviate this problem, so I don't want to throw good money after bad. . .
Thanks for taking the time,
Bruce

 

[Bubbletrubble]

I can use either splitfins or blade-style fins near the ocean bottom without kicking up any silt.

It's not the fin design, per se, that causes one to kick up silt during a dive.
It has more to do with how close the diver is to the bottom, the type of "sand" on the bottom, and the type/amplitude of the kick being used.
A frog kick directs water movement directly behind the diver. (BTW, it is possible to do a frog kick with splitfins...it just isn't as efficient as with blade fins.)
A flutter kick creates a fair amount of water movement downward and upward, in addition to backward. The downward water movement is what causes the silting.
A bent-leg modified flutter kick is less likely to kick up silt than a traditional flutter kick.

I'm not sure what qualifies as "documented proof" in your book. I've recorded video clips of my buddies using various fins with different kicks. They've recorded me using various fins with different kicks. My findings above are based on what I've observed. Surely, you could conduct similar studies with local divers in your area.

 

[Pullmyfinger]

There is no documented proof, just some "Bigfoot sightings".

Both styles will propel you through the water.

One one cooler than the other, sort of like shoes vs. Crocs.
It is up to you to determine which is which.

It doesn't really matter, because all the cool people are in the Force Fin forum. hee hee.

-Mitch

 

[RJP]

I'm now wondering if there is any documented proof that a blade fin is any better at NOT kicking up sand than a quality split fin?

Fins don't kick up sand... divers do.

 

[Teller]

Your trying to fix a technique issue by applying an equipment solution. The issue is not your fins. You can do the same kicks with split fins as you can with paddle fins however in my opinion paddle fins are more efficient at certain kicks such as frog kicks and back finning. Learn to frog kick and try to stay of the bottom.

 

[JamesK]

A nice stiff blade no gimmick fin like Dive Rite EXP's or Jet Fins coupled with a good technique are the answer. I only mention the fins because they are more efficient for non silting kick types then a split fin. Whatever fin you have work on technique. Like mentioned above using a frog kick, modified frog kick, or modified flutter kick, coupled with good trim, will keep that silt down. I mention trim because using any kick and not being in good trim will still direct the force from your kick to the bottom and cause silt. As you get closer to the bottom, start bending those legs so your feet are higher up away from the silt then your body.

I also prefer a regular fin because they make a backwards kick much easier.

My YouTube is acting crazy right now, but if you look for videos with the tags of "cave diver fin kick", you should get some good "how to" videos showing these kicks.

 

[TSandM]

Bubbletrubble pretty much nailed it -- controlling silting is more a matter of controlling trim, and using a kick that propels water BEHIND you, than it is the fins you use. However, it is my observation that, because the twin blade of splits are so soft, and twist so easily in the water, it is more difficult to control the precise path of the water coming off them. Even when frog kicking, some water is propelled downward.

My suggestion would be to get some coaching in trim and propulsion techniques, and then have someone video you again. If you aren't happy with the results you've achieved, change fins. (But one warning -- it is FAR more difficult to learn the new kicks in splits, simply because they don't give you the same proprioceptive feedback that blade fins do.)

 

[TheYellowSubmarine]

Frog kicking (or "

cave diver fin kick" to some ​

) works wonders for not disturbing sand.
With shorter stiffer fins (Jet Fins or something similar) some of the more versatile kicking styles (back-finning, helicopter turns) are much easier too.
Not silting up is very important in tech/wreck/cave diving, which is why so many tech divers use these fins.

The ability to back-fin to hold my place in current/surge makes photography much easier

 

[boulderjohn]

The ability to back-fin to hold my place in current/surge makes photography much easier

I think this is an important point. Not only will those kicking techniques help keep the sand in place, you will become a much better photographer as you learn how to control your direction and your position in the water this way. You will be very happy to learn the back kick, and it is much more efficient to do a back kick in a stiff blade fin than in splits or a soft fin.

 

[jghflash]

proprioceptive feedback......cool!