Turbo Tunnel Fin....more

General Discussion
1

I’ve read what I believe are all the posts re turbo tunnel fins and I would like to add my 2 cents worth…

Like all things there are some positives and negatives…first the negative, and it’s a big one. You absolutely cannot use this fin in waters where kelp grows without experiencing some frustration. This fin is a “kelp catcher” extraordinaire! It will catch kelp and pitch you off the front of your board faster than you can think “arrrghh!” It will also rip or snap full strands of kelp and drag them along with you. You can count on this for 15-25% or so of the rides you get in kelpy waters. The second bad thing about Turbo tunnel is the complete lack of customer service if you buy online like I did. The sellers do not respond to contact queries from the turbo tunnel website, nor do they respond to email replies from email they initiate (purchase confirmation). And finally a small but pesty thing when spending $80 bucks for a fin…you get a free t-shirt and they don’t stock size large…so you get what they send you. That may or may not be a problem for some of you.

The positive things are that this fin provides a great deal of longitudinal stability to the board. When nose riding (for definition here the front 25% of the surfboard) one can be much less precise in their footwork. Not to worry if you mis-step on the inside or outside rail, the board stays steady. Re nose riding I did not experience a noticeable difference from my other fin (Wingnut 9.5" Cutaway) re tip time. There was also no appreciable increase in drag with the turbo, although oddly enough the board feels like it’s dragging. But I can make as many “critical” sections with the turbo as with the wingnut. Turning the board with the turbo is also no problem. Whether you like to snap turn, throw a big cutback or make long sweeping bottom turns, the turbo tunnel did not fail and provided stability and drive throughout.

This feature of stability on the longitudinal axis of the surfboard is, I think, a big deal. Stability and lift can be built into the surfboard (shape) and to a lesser degree be enhanced by the fin you use (well, maybe not the lift). I think the claim turbo makes re lift is weak at best. Supposedly the built-in watershaft “sucks” the tail of the board down. That didn’t seem to be the case in my experimentation. Of course I tried the fin in a number of different positions in the fin slot and the further forward the fin placement, the “looser” the turns, but again there was no appreciable increase in tip time the further forward the fin was placed. (One might think this would be the case because the watershaft is deeper in the water, compensating for tail rocker.) I just purchased a Rainbow “Tomahawk” 10-inch fin. I’m interested in whether or not this fin will provide the same longitudinal stability as the turbo without the kelp catching defect of the turbo.

In Summary: The added longitudinal stability experienced with the turbo makes it worth the purchase. I think this would also add flexibility to a longboard primarily kept for smaller waves, in that the same longboard could be surfed in larger waves, where stability plays a more prominent role in the overall wave characteristics that would be encountered. Playing with fins is one of the funnest things you can do in experimenting around with your surfing, surfboard(s) and surfing style. Maintainng a “quiver” of fins is cheaper than buying a board every time you are looking for a change, and will add to your satisfaction and knowledge of surfing.

2

One of our grumbly older competition longboarders initially laughed at the tunnel. Then he rode it. Now he won’t take it off his board. He specifically likes

  1. longitudinal stability for noseriding

  2. rear end hold in floaters

He’s a good guy, and initial skeptic, and now a convert. It is somewhat amazing that they charge $80 for a fin that pops out of a casting mold, though. Starfins are made from the same material - for $45 AU dollars.

Not much kelp up here, though…I guess a plus for the tunnel.

3

O.K. I admit it. I’m also a skeptic. Sometimes I wonder if the unusual fin designs and configurations work because of the inovations or in spite of the inovations. I’ve ridden five fin boards and six fin boards. They both worked(five better than six). I tried the fcs “Free Willy” fin and it worked(not better than the Tom Carroll Model). I have not tried the tunnel fin but have seen them work. But, do they work better than a more traditional shape. It seems to me the place to look for a better fin design is in nature. Can we design a better fin than 30-50 million years of cetacean evolution? Or, design a better fin than 400 million years of fish evolution? A better fin than God? I saw a bitchen fin on the back of a dolphin a couple of weeks ago. Halycon’s new fins a couple of post back remind me of tuna fins. Speed and maneuverability.

4

Sounds like the tunnel fin has similar attributes to the Cheyne Horan star fin – bad kelp catcher but adds stability to the board. Nice for certain things (floaters, getting hit by white water). It’s really different than standard fins in that respect. Can we design a better fin than God and/or evolution? I don’t think he’s tackled this particular issue, because fish, dolphins & sharks aren’t surfboards, so they have different needs.

5
Quote:

Can we design a better fin than God and/or evolution? I don’t think he’s tackled this particular issue, because fish, dolphins & sharks aren’t surfboards, so they have different needs.

Well said Keith…

6

True enough. But, fins on both have to slice through water, change directions, prevent spiralling outof control.

7

They tried making early flying machines to mimic birds. It didn’t work. Look where science and technology has taken the aircraft now. Fins must eventually go this way. Man is in control of the evolution of the surfboard, not nature.

8

Man-made fins are at 1/1-millionth the sophistication of nature’s. Ours are rigid, practically speaking; ours don’t attach to muscles (no self propulsion); our have no working coatings, scales, etc – much less self-healing capability. Ours barely work in the water/air interface and don’t adapt to differences between them…just compare a surfboard fin to the working end of a flying fish! we really are just bumblers in the grand scheme of things.

I don’t see anything wrong with emulating a magnificent creation such as a dolphin or skipjack - mankind has always looked to nature for ideas and inspiration. But, it’s like a crayon drawing of the Mona Lisa, and will always be that way…

9
Quote:
Quote:

Can we design a better fin than God and/or evolution? I don’t think he’s tackled this particular issue, because fish, dolphins & sharks aren’t surfboards, so they have different needs.

Well said Keith…

true…never seen a fish or a shark hang ten…they don’t need to. a surfboard is not a fish and never will be, get over it.

10

I have tried both the turbo tunnel and the winged keel which I sell. I really did not see a huge difference in the turbo tunnel and the wingnut cut away and I thought the turbo tunnel had a bit of drag to it. The keels seem to me to drive better and accelerate through turns much better. Also $80.00 for a popout fin seems a bit high.

11

Actually,Keith’s second post said way better than I could. What I’m thinking is we should look to nature to make better inovations in fins and boards. Its pretty obvious a surfboard is not a fish. But, all surfboards that I have seen are variations of the basic fusiform shape. Like most fish and whales. 99% of the fins I have seen on boards I have also seen on fish or whales. The inspiration is already from nature. Like I said, “I’m a skeptic.” When I see a hole in the middle of the fin like the tunnel I think Hmmm. Does it work because of the inovation or inspite of the inovation? Mr. Shipman. What am I supposed to be getting over? Just throwin in my two cents. You can print it and use it to wipe your fanny if thats what you think its worth. I don’t care. Mike

12

fat penguin…turbo tunnel fin…keep em coming

13

Put a powered propellor in the tunnel fin, then you might have something, something I wouldn’t want to surf.

14

Bert, what do you think of the Horan star fin? (I’m assuming you’ve tried one at some point…) Anything there worth pursuing, or just another experiment?

15

Keith, I too hope to hear Berts feedback. In my experience with the star fin it went pretty fast, which was good, but too many other drawbacks for me. It caught seaweed and my leash constantly. It provided too much lift for me on rail turns, I’m about 60kg. I made myself a smaller one, better but still had leash problems. Very easy to pivot, but didn’t feel nice for me on drawn out turns due to the vertical nature of the fin. I didn’t like the knify leading edge foil, a fuller forward foil was smoother in transition. Only my opinion, hope it helps.

16

I don’t wear a leash when I use the star fin, and I don’t use it where there’s seaweed – as you say, 2 big issues with that fin. I never noticed the excess lift problem – could be that you had it in a board with a lot of tail rocker, which could effectively change the angle of attack of the wings… I felt like it held the tail into the face of the wave when doing more vertical maneuvers, and it added something to the board’s stability when getting slammed by a lot of white water… a very weird sensation to ride, overall.

One other thing on the plus side, its a great conversation piece. A couple of times I made some quick friends at otherwise hostile breaks just by having that fin as an icebreaker…

17

Hi - my first post - I’ve used Star fins on and off for a lot of years. The legrope hangup is a serious issue. There were some hollow legropes around when they first came out in the 80s that floated up and away from the fin. There wasn’t such a problem with the things then. Its a serious bummer when you go trip to the tip and come up a couple of feet short.

The other thing I noticed was that they don’t have the same kind of ability to draw a long turn like a raked fin. Seem to be more efficient in getting vertical and for real tight turns on boards shorter than 8 foot - the shorter the better really - which is exactly what Cheyne Horan had in mind, I guess.

18

Hey DMAN – glad we could lure you out of “lurker mode” – always nice to see a new face, so to speak. Are you in OZ?

19

Yeah Keith

The land of OZ, on the Gold Coast in Queensland. And I have been a ‘lurker’ for a while. Didn’t want to rabbit on without something to say.

20

yes keith i did have one in my colection as a kid, i made one as a school project in 83 after seeing the americas cup winner finnally unveiled here in perth on the news one night,thought it might work in surfboards,i made a full single fin one like the winged keel and also made a small tail fin version for a thruster…i used perspex ( acrylic plastic) glued two 5 mm peices together heated and bent the tips for the wing…

at that time i really had no idea design wise was just doing stupid stuff with 1,2,3 and 4 fin boards …

i personally dont think they are a valid design for performance surfing, but i wont completly write them off coz like alot of designs they sometimes have a particular time and place where they do function…

the observations you guys made are completly correct from the point of veiw of foils physics and what the fin should feel like…

the wing will have an affect either to pull you down lift you up or be neutral depending on the rocker of your board and if your box is set level…

also a more vertical fin will have a more pivoty feel but lack drive out of turns coz there is no resistance from the tip of the fin ,where as a raked fin gives drive out of turns especially in soft waves ,also a raked fin resists stalling ( like a delta wing aircraft) a vertical fin that has a lot of leading edge will react very quickly when given an angle of attack ,the wave needs to be sucky so once youve done your pivoty turn you basically fall back into the wave to keep the flow …a vertical fin in soft waves will have a turn and stop feel…

for peformance shortboarding ,na you wouldnt waste your time

the only area i could see any advantage would be for a 9’ plus longboard noserider,the deep vertical aspect of the fin would help with stability in walking forward and back ( not so tippy) and if the wing angle was set right it could create down force on the tail thus enabling good hang time …it would be the sorta thing you could use to nose ride when the waves are real soft and you cant get the curl of the wave over the deck …the fin would create enough down force to ride the open flat face on the nose …you would have to design the board around that theme tho…so it would be very specific…

interestingly…even tho the fin has limitations they would actually go best in a MCcoy style design ,coz in small waves they would lack drive out of turns which is made up for by the wider tail which could still drive off a flat section…and give some pivot to an otherwise hard to get on the rail board…

still not a good package overall tho…

regards

BERT