What fin set up are people using on directional?

[Do-it]

Nay nay nay..... thrusters are for bigger waves and higher winds.. quads only slightly more up wind but way slasher.

[BWD]

What size find did you swap out? All 4?

http://www.surffcs.com/shop/surf-specia ... pc-tri-set

these, i have run as both a twin and with the stabilizer fin as the call it. I find it much smother with the stabilizer.

I usually use the futures version of this type of set up, "AMT" set, with my all-around surfboard that I kite and surf (5'11", 34L)

Thrusters with full size trailers give a little more slash-ability with predictable release for good waves but give up speed and upwind.
Downsizing the trailer reduces the drag but helps keep the tail under control. Running as a twin only and the tail skates out a little wildly if your pivot point/pressure is not exactly right, but that's fun too.
Quad gives tracking, easiest jibes and best upwind, not so fast carving. Can help hold things under control but if too large can act like hydrofoils and do the opposite.

Next experiment for me will be quads with tiny trailers...

[magic%20Ed]

When searching you should be able to find enough fin discussions (here and somewhere else).

About one setup turning faster then the other: this needs a bit more specification. In general a thruster will turn easier on a smaller surface (a small arch), but a quad will turn with a higher arch speed (but a bigger arch). When to use a quad, when a thruster? Each board rides best with a specific fin setup depending on the conditions (and your level of riding). So buy a 5 fin set and try! You can hardly go wrong with a medium setup, unless you are really heavy.

[tegirinenashi]

Why such thing as quad even exists? Those pairs of fins on each side are so close to each other, that begs a question: wouldn't just two slightly bigger fins be indistinguishable from quad? And, before you ask, windsurfers use just one large fin and they are fine making tight turns, even with humongous board hulls.

voodoo indeed.

[BWD]

well, 4, 4" fins will give -almost always- more hold and drive than 2 bigger fins with the same surface area. but the quad can be broken out easier, too, on most set-ups...
...and 4 higher AR fins may give more lift, with little or no drag penalty compared to 2 keels, so great upwind.
...and having quads, with flat foiled fronts and rears foiled symmetrically or 80/20, will avoid the problem of all fins hooking up or breaking out at once, leading to awkward turns or spills...
but twin plus trailer is fun, so are twin keels, sometimes.

[knotwindy]

Also remember, the water of the front fin can change the water flow across the back fin, so it may not be the same as one larger fin. Depends on toe, angle, speed, pressure, etc.

[tegirinenashi]

The idea of splitting surface area into numerous fins is flawed. Suppose, 4 fins are better than 2. Then, perhaps 10 fins are even better than 4? Where does this proposition end?

As for the idea of front fin changing the water flow across the back fin, I can't see how this can be beneficial in any way. Yes, front fin can disrupt the flow, but the effect is creating a turbulence behind, and turbulence can't be good for grip.

[knotwindy]

Those are two interesting assumptions, based on what? How about diminishing returns, some small # of fins might improve things but more might make it worse? As for water flow across surefaces, are you a hydrologist or studied this in detail? Do channels on the bottom of the board help channel water flow? So why not fins?
To be clear, I have no idea if these are true or not. I am asking, is it possible?

[Koura]

Stiff glass fins on the side, smaller (quad fin) in the centre.

[Onthewater860]

Has anyone tried a stubby 5th fin?