Can somebody tell me what is faster to paddle on the flat ?
Single
Twin
Tri
Quad
I would suspect single fin ?
On a wave the answer may be very different ?
I suspect you have a "normal" (allround) board with many boxes, and want to know what fin setup to use, I will answer for this case
(If you were to build a board, the answer would be different)
Single.
On a wave, things are totally different, as the propulsive force is not given by the paddle but the interactions of the waves and the push of your legs on your fins & hull. So the answer depends on how you surf and your conditions.
But as you seem a beginner (for asking this question), single will be faster until you know how to turn and use the wave power.
Select to expand quoteLondon said..
Can somebody tell me what is faster to paddle on the flat ?
Single
Twin
Tri
Quad
I would suspect single fin ?
On a wave the answer may be very different ?
Single.. for both flat water and wave.. IMO.
Well, it would be perfectly possible to create a twin or Tri setup that is faster in flat water than a single, by for instance having no toe-in or cant on the side fins and having a smaller total fin area than on the single you were comparing it to. So it's probably not *necessarily* the case that a single would create less drag than a multi-fin setup. But in current practice right now with the designs we have, both of fins and boards, generally a single is faster than a multi-fin setup, although some fin pioneers have been experimenting with multiple fins (eg. Larry Allison, or take a look at the Coreban Turbo).
Select to expand quoteArea10 said..
Well, it would be perfectly possible to create a twin or Tri setup that is faster in flat water than a single,
That's why I said "If you were to build a board, the answer would be different".
Note that you could have a twin set up that could be nearly as fast as a single, but not as fast. why? because the single is already in the optimal place where the water flow is assured to be straight. Whereas twins are in a place where the water flow is not, and how much angle the water flow have relative to the stringer depends on the hull shape, the water speed, and the depth: on most boards the water will have more angle close to the hull than deeper...
This means that it will be possible, but quite tricky, to have twin fins aligned with the water flow... and only for a specific speed.
Of course, you could have a design that could offset the induced drag by a better stability in chop so that the rider could apply more paddling power
Select to expand quotecolas said..Area10 said..
Well, it would be perfectly possible to create a twin or Tri setup that is faster in flat water than a single,
That's why I said "If you were to build a board, the answer would be different".
Note that you could have a twin set up that could be nearly as fast as a single, but not as fast. why? because the single is already in the optimal place where the water flow is assured to be straight. Whereas twins are in a place where the water flow is not, and how much angle the water flow have relative to the stringer depends on the hull shape, the water speed, and the depth: on most boards the water will have more angle close to the hull than deeper...
This means that it will be possible, but quite tricky, to have twin fins aligned with the water flow... and only for a specific speed.
Of course, you could have a design that could offset the induced drag by a better stability in chop so that the rider could apply more paddling power
We brought 2 naish beginner windsurfing boards to teach kids ..identical shapes ...one was a twin fin the other a single ..the twin fin was more stable and turned better but the single was way faster ..we did get the twin fin to get almost as fast , by putting smaller fins on it .but the single ,always was faster ......
