turbo tunnel fin!?!?!?

[surfrguy91]

does this actually make a difference???? or is it there to charger u more money

[Roy Stewart]

They work, but Vort-X works far better !





Tunnel fins are one of the new frontiers of surfing.

[surfrguy91]

do u hav tha site for tha vort-x?

[bluesnowcone]

i used a turbo tunnel on my 9' perfromance board at saunton in the uk and it made a huge difference. i used the 7.5 version and i could hold hang 5's longer, the board was more stable, but what suprised me is the tunring of the board was alot better. over all they are realy good

[Phil]

ive heard alot of mixed views on them best to try one out if you can before you spend the cash and find out its not for you

[Roy Stewart]

Hello Phil,

I think I can clarify the issue here.. . . .

The main reason for 'mixed reviews' regarding the turbo tunnel is in my opinion due to the fact that the turbo tunnel marketing does not fully explain what the fin does. . . . . this leads to it being 'bolted on' to a lot of different boards without an understanding of how to set it up for the best results. Specifically, the lift angle of the tunnel in relation to the bottom rocker is critical, and also the rider position determines whether or not the fin is lifting for drag reduction or pulling down for noseriding. Basically it's like having a new dimension in surfing control. . . ideally the surfer needs to have a mental picture of how the controls work. . . without this some people will get lucky and have a good experience with the fin while others won't. It's pretty simple once you understand it, but it really needs to be explained.. . . . and just 'trying one out' won't necessarily help unless you know what to expect.
These comments apply to all horizontal area fins.
A secondary reason for mixed results with the turbo tunnel is that it does have some design drawbacks. . . . .. the Vort-X tunnel is a much more versatile and powerful solution. I can explain why if you like.


Regards,
Roy

[Roy Stewart]

i used a turbo tunnel on my 9' perfromance board at saunton in the uk and it made a huge difference. i used the 7.5 version and i could hold hang 5's longer, the board was more stable, but what suprised me is the tunring of the board was alot better. over all they are realy good

Yes tunnel fins provide loads of drive and lift and holding power which can really help the turning of the board by maintaing speed through the turns.

.

[Roy Stewart]

do u hav tha site for tha vort-x?

Hello Surfrguy91.

If you hang around at http://www.olosurfer.com in the next week or so then you will see a Vort-X tunnel fin page appear, we are just waiting on a small shipment of Vort-X tunnelfins and there will be some for sale on the site. We will do a special introductory offer for the first few.

The 6 inch tunnelwhich will be available is a reproduction in glass of the tunnel on my 'Resolute Salmon' foilboard, it is a very powerful fin, and very fast.

The tunnels are glass on only, however due to the incredibly strong shape of the Vort-X tunnel they can be applied with a few drops of superglue or resin, so no need to pay a manufacturer to install them.

The Vort-X site will have have all the necessary infomation needed to fully understand the Vort-X fins and how and where to nstall them.

There are a few pictures of tunnels on olosurfer at present.

[GowerCharger]

gimmick.
There was loads of these types of things about in the 80s.

[Roy Stewart]

Tunnel fins are most certainly NOT 'gimmicks', and furthermore, there were not 'loads' of them around in the eighties. . . .. . there were a few primitive attempts at horizontal wing fins, they were not fully understood or developed at that time, but they are very well developed now.

There were a few tunnel fins built in the 60's which resembled the Vort-X fin, but again, they were not fully developed.

Tunnel fins and other horizontal area fins deliver significant gains in speed. . .. . the simple fact is that underwater wings have a far superior lift/drag ratio. . . ... . and this means less drag and more speed. . . . particularly in the case of the Vort-X fin.

[Phil]

the Vort-X tunnel is a much more versatile and powerful solution. I can explain why if you like.


Regards,
Roy

please do

[Sweet!]

I had a go with one but there were too many other things that could have accounted for the difference. The board wasn't as thick, different rails, different pretty designs on it... oh...I couldn't tell if it made much difference.

I'd love to try one on my own board tho.

yay.

I still haven't tried a single fin yet. I've got a thruster set up, I'm still confused:

Single fin is more stable?

Thruster set up is more manouverable?

yes??

So what happens when you have one big fin... and then the other two also.

And roy... what the hell is that?? looks.. interesting?

[grub]

Still hard to believe there are people on these forum that haven´t seen big Roys fin . Mate the end view is magic, pity about the side . A couple of points that I would like your view on Roy...

From what I understand with regards to tunnel fins, board design in terms of rocker and inparticular tail rocker dramatically effect the performance characteristics of such fins far more than conventional fins. This inturn is one reason for which many people either give them the thumbs up or start going off about them being the equivalent to having a bag of cement straped to the back of their board.

With respect to the tunnel fin trade marked "TURBO TUNNEL". That is a mass produced item aimed at a mass market and consequently promoted to achieve the financial results. Therefore this fin is a generic item with no provisions built into the design inorder to permit the user to fine tune such an item that undoughtably requires it.

• As I understand the Vort-X was modeled off your tunnel fin that was attached and tested on one of your olos. How relevent is this design without alterations when applied to a std. type Longboard having (as you would term) no definate or single “sweet spot”.
• To achieve the best results from fins such as your example named the Vort-X tunnel wouldn't they require some eliment of consideration with respect to the rocker on the board for which they are to be applied too?
• Is the Vort-X tunnel designed to increase speed and if so do you feel it is of an advantage to fit such a fin to std longboards designed to impair speed inorder to increase their nose ridding ability?

I always like to here your opinion Roy; you help keep the cogs turning in my head, keep up the good work...

[Roy Stewart]

As I understand the Vort-X was modeled off your tunnel fin that was attached and tested on one of your olos. How relevent is this design without alterations when applied to a std. type Longboard having (as you would term) no definate or single “sweet spot”.

Hi Grub,

Glue on on and find out !

To achieve the best results from fins such as your example named the Vort-X tunnel wouldn't they require some eliment of consideration with respect to the rocker on the board for which they are to be applied too?

Yes, the standard Vort-X fin is set up parallel to the bottom, so the lift angle is largely determined by the tail rocker around the fin. If the standard Vort-X is set up on a board with pronounced tail rocker it will pull the tail down whenever the rider moves forward off the tail, and will thus act as a noseriding aid. . . . this is a legitimate use for the fin, but just isn't my kettle of fish, which is why I recommend using the fin on a flatter tail rocker.
For the adventurous rider, the fin can be set up with a positive angle of lift in relation to the bottom. .. . thus if there is pronounced tail rocker, the fin can still be used for increased speed by setting it at an angle of lift which represents a flatter tail rocker. . . . as the board speeds up it will lift the tail, and effectively act as if the rocker is flatter. The biggest speed gains are to be had be using this trick, regardless of the rocker. . . because it takes more load off the bottom of the board. . . but it isn't for the faint of heart, because the acceleration can be dramatic and at times, unexpected. When set up at a positive angle of lift in relation to the bottom, the board should be pumped for speed. . ... drive hard off the surfboard bottom, and then release to let the wing take over, repeat.

Is the Vort-X tunnel designed to increase speed and if so do you feel it is of an advantage to fit such a fin to std longboards designed to impair speed inorder to increase their nose ridding ability?

Yes the Vort-X fin is designed to increase speed, essentially it is a wing, and the pilot can direct the wing by trimming the board fore and aft, trim aft for speed, and forward to noseride ( )

If you want to noseride and slow down, the fin can be used for that too, anytime you are on the nose it is going to hold the tail down, but it will still make you go faster when on the tail ( ).

We use the Vort-X fins on shortboards as well, at least my son James does. . . he has had several pairs of boards where one has the Vort-X and the other doesn't. . . he is addicted to the tunnel.

Then there's the increased holding power on steep walls. . . ..

Thanks for your questions, sorry if the answers are rather general.

.

[Roy Stewart]

BTW I have published a few of these questions on olosurfer.com, please let me know if it isn't cool

[Roy Stewart]

the Vort-X tunnel is a much more versatile and powerful solution. I can explain why if you like.


Regards,
Roy

please do

As far as the Vort-X being a more powerful fin than the Turbo, it is mainly due to lift area . . .. the turbo has about the same as a toilet roll approximately 8 square inches, whereas the Vort-X 6 has 24 square inches. . . . which means that you fly earlier and faster. The diameter of the water vortex leaving a turbo is about 2 inches, whereas the Vort-X 6 has a vortex diamter of 6 inches. Remember that more tunnel equals more lift, and the nore tunnel based lift you have, the more speed you have. . . . increasing the role of the underwater tunnel in the surfboard equation reduces drag and increases speed. There are so many pounds per square inch of lift generated by underwater foils, so more foil equals more lift.

As for versatility, here are a couple of reasons:

1) The angle of attack able to be handled by a long skinny tunnel like the turbo is much less than a wider mouthed shorter tunnel like the Vort-X, this, combined with the greater power of the Vort-X, means that the Vort-X will be working more often than the turbo. . . . to put it simply, the narrow entrance of the turbo will start funnelling under a much narrower range of water flow angles. ... . the wider opening of the Vort-X will handle a wider range of angles during turns.

2) The centre of the turbo is misaligned with the fore and aft axis of rotation of the surfboard, this restricts rail to rail movement and turning ability, particularly as the board goes faster. . . and sets up heavy side loads on the turbo fin. . .. . this is, in my opinion, one of the reasons why the turbo fin has a small tunnel. . .. . a bigger tunnel would rip the fin out of the box. . . . . we had a turbo style fin (we call it the tunnel on a stick model) with a four inch diameter tunnel on it, and it destroyed itself due to side loads. . . . Cheyne Horan had one which was very similar ( a big tunnel on a stick) and he told me the same story. . . he wrecked the fin at backdoor pipe just by riding it. . . . the board will also tend to 'trip up' on the tunnel when going rail to rail.
Vort-X fins on the other hand, have the axis of rotation very close to the axis of rotation of the board, this means that the fin is very unobtrusive in it's rail to rail handling characteristics because it offers zero rail to rail resistance.
3)In terms of efficient water flow the Vort-X wins also. . . . the annular wing form of the Vort-X has the lowest drag of any fin shape due to the fact that it has no fin tip turbulence (it has no fin tip) . . . . parking a tip on the tunnel is not ideal.
4) Also regarding water flow efficiency and low drag, the tunnel fin configuration does not require a thick fin wall. . .. . the thinner the fin wall is in relation to its length, the less drag the fin produces . . .. . the turbo has a very thick fin wall (which is also obstructed in two places by the vertical fin it is mounted on) . .. . whereas the Vort-X fin is only 2 millimetres thick. . . . . an impossibility with conventional fins. . . . . and the payoff in terms of low drag is more speed.

The Vort-X has very low drag and very high lift

[grub]

Thanks Roy, as a result of past discussions with you I have set about designing a wooden board modeled more closly to the conventional longboards as opposed to your olos. Don’t worry though still havn’t disregarded your olos for the future.

I will give this fin some more thought but at this stage I was planning a more traditional keel fin for my first “atempt”... old school, less performance but a style of board that I have been interested in for a while. Almost completed the initial planning on paper but would like to model it in 3D just for the fun of it (there goes a few more months). I am at the stage where I need to find out what woods are available.

• Have you ever experimented with woods of different modulus of elasticity for the tail compared to the rest of the board?
• I am thinking to build the tail different hopping to add a bit more flex into it, what are your thoughts on this?

I won’t go into detail on the design yet as every time I look at it, it changes... for now I plan to start with a small 9’6”, if everything goes ok I will look into something a bit bigger for the future. If possible Roy, I would appreciate if you could have a “captain cook” at my production plan to give me your opinion.

[Roy Stewart]

Happy to have a Captain Cook (James) at your design, a tunnel can be added behind your traditional keel fin later !

Just leave about 4 inches of space behind the keel fin

Regarding tail flex, I haven't tried to concentrate flex around the tail as this has the slowdown effect of creating an accelerated tail rocker during turns,I prefer to have the entire board behind the riding position flex during turns to create a nice fast even curve. . . thus we allow the whole board to flex. By the way a tunnelfin increases board flex a lot because of the vertical power of the tunnel. . . the board tail will not sink under load, wasting power, rather it will transmit the power effi=ciently i the same way as a dolphin tail does.

Timber wise, if you want more flex at a given board thickness then I suggest using balsa, it is softer and flexes a lot more,making it easier to get flex over 9 feet. for even more flex the deck balsa can be laid diagonally.

For the most overall flex at any given board volume, use a profile as close to the parallel profile as you can . .. having the board thicker in the middle concentrates flex at the ends, a no no in my book anyway.

Cheers, thanks for a great rave, time for a Billy cuppa made on the open fire.

Dog ate my pipe

[grub]

I have already planned 45 degree dark/light wood alternating clading for the front 3' and back 2'. I was planning to stear clear of balsa in this section (although I know it would have good flex properties) for the light wood dark wood alternation as the dark wood is almost certainly going to be a hard wood to achieve the color variance. By using balsa for the lighter colour wood I was worried about the large variance in material properties (between hard wood and balsa) and have concequently steared clear. the main suporting members in this area are the rails and so called stringer althought the stringer is more a supporting member for the hull than that of a conventional foam/stringer combination.

I was thinking of using it in the center section of the deck where the rails are thicker and consequently lack flexability. I feel that by using such a material in this section that is more flexible than the rails the likely hood of delemination (ahh yes I am planning a volan deck patch in this section) is less likely to occur.

The design is slightly different to the examples I have found as the supporting structure is the rails and the center piece that I am at present calling the stringer. I guess the structure is more like a crustation then a bone structure of a fish... I don't like the idea of constructing an internal structure through which the outer material is atached, I have opted to produce the outer structure and build onto that.

My idea around the slightly flexable tail when compared to the rest of the board is that it would slow down as you tightened in the bottom turn absorbing energy in the tail section and releasing as you exit the turn providing further forward thrust. Also antisipating that it would serve benificial to forces durring nose ridding. Maybe I am wrong, just turning a few cogs in my head. Enjoy your cuppa mate.

[surfrguy91]

do u hav tha site for tha vort-x?

Hello Surfrguy91.

If you hang around at http://www.olosurfer.com in the next week or so then you will see a Vort-X tunnel fin page appear, we are just waiting on a small shipment of Vort-X tunnelfins and there will be some for sale on the site. We will do a special introductory offer for the first few.

The 6 inch tunnelwhich will be available is a reproduction in glass of the tunnel on my 'Resolute Salmon' foilboard, it is a very powerful fin, and very fast.

The tunnels are glass on only, however due to the incredibly strong shape of the Vort-X tunnel they can be applied with a few drops of superglue or resin, so no need to pay a manufacturer to install them.

The Vort-X site will have have all the necessary infomation needed to fully understand the Vort-X fins and how and where to nstall them.

There are a few pictures of tunnels on olosurfer at present.

thanx im getin a shortboard pretty soon (could be months )and wanted somthin different for it