Surfing Waves

Long board - faster, holds a line better, more stable.
Short board - more manouverable, better for tricks (but not all tricks...), harder to start out on for a beginner.

Is the above anywhere even near the truth? Or am i oversimplifying?

That's a wee bit over-simplified, but yes.

The only thing actually wrong is saying longboards are faster. Generally a shortboard would be considered faster (although obviously depends on board, wave, surfer etc).

They're so very different we could post pages and pages about it. Best way is to find out yourself. Learn on a mini-mal and see in which direction you progress, have a go on both, see what you like.

Drowning.....did you get my PM?

yep, id say shortboard is faster and holds a line better, but thats by the by.

like drowning said, go for a minimal or foam board when your a beginner, ten as you progress youll naturally come to a desision on what board you want next. If you find your wanting to do quicker manouvers and rip up a wave then move smaller, if you find your happy just cruising along on mellow waves then youll go for a longboard. But i wouldnt choose either to learn on.

Well on the skiing front im into my big lines down deep powder, cliff drops and speed - i can take or leave the park, i dont really care for it all that much. tricks arent really my forte. i usually ski on things that are 10-20cms "too long" for me, really, for the extra speed and stability.

so translated into surfing, i guess i would go for a longboard... but yeah, i'll learn to walk before i start running! and when im good enough, i'll try both long and short, and see what they are all about.

Cheers guys, you are all being phenomenally helpful to an ignorant beginner such as myself


edit - so hold on, a lot of people are saying shorter board - holds a line better and is quicker... with skis this is the exact opposite... longer skis, more speed, shorter skis, more manouverable. this is getting a bit too abstract for my tastes!

i only say that as longboards can slip sideways on steep waves, not an expert on them as ive only been on a longboard once.

Some of you are going to squeal.

But I think people interpret "speed" incorrectly.

A shortboard accelerates more easily. Combined with it's greater manoeuvrability it results in a board that dances in and around the pocket. And looses power quickly once it gets out of it.

A longboard has more inertia. Combined with the way it holds lines it makes for a craft designed to trim and is easier to hold in the pocket. This also means that a longboard can continue to glide for longer once it's out of the pocket.

Just my interpretation, tho.

I think it's a personal choice and a mood thing.

-doug

This is all nonsense so far because length is only one board design factor, it is really silly to start saying that board speed or holding in ability is dependent upon length because whichever side you take there are a designs which disprove your position.

Board speed is dependent upon the thrust/drag ratio of the board and the size and length of the wave.

Thrust/drag ratios are not simply board length dependent.

Hi Roy,

Of course other things matter. Rail profiles, for example... I suppose when someone asks something like this I automatically assume the increased mass that goes along with a longer board. Perhaps that's a bad assumption.

Comparing a 5'9" shortboard and a 12' longboard, where both are of "normal" width and thickness for a board of that type, the longer board will have more mass, surface/wetted area and inertia. Probably best not to get into "true wetted area" on here (maybe leave that for Swaylocks.com - what do you think?).

Perhaps you would care to share with us your view of the impact of length where all other factors are (roughly) equal?

-doug

Good, discussion on the physics of boards. I feel a lot less confused now!!

How would you feel if i started talking about the comparative merits and weaknesses of a 110 underfoot against a 69underfoot with a smaller sidecut radius?

dougirwin13 wrote:Some of you are going to squeal.

But I think people interpret "speed" incorrectly.

A shortboard accelerates more easily. Combined with it's greater manoeuvrability it results in a board that dances in and around the pocket. And looses power quickly once it gets out of it.

A longboard has more inertia. Combined with the way it holds lines it makes for a craft designed to trim and is easier to hold in the pocket. This also means that a longboard can continue to glide for longer once it's out of the pocket.

Just my interpretation, tho.

I think it's a personal choice and a mood thing.

-doug

few things wrong with that. most people believe that intertia is how much force an object has...which is completely wrong. the bigger the inertia is for something, the harder it is to move. such is the more mass you have, the more inertia, which makes it harder to move like a big rock compared to a small rock. so a longboard does have more inertia than a shortboard, but that definately does not make it hold lines and trim faster. take for instance, a longboarder and a shortboarder catching a wave and going straight towards shore without turning. the only reason you can stay on a longboard longer is because it of course, it has a bigger bouyant force than the shortboard. bigger weight to bouyant force ratio or itll keep you floating longer because there is more foam. i was a physics major...

but i think all speed depends on the surfer, sure the type of board helps, but its all the abilities of the surfer, although certain types of boards will help you fly faster

What most people ignore when talking about heavy versus light boards is that surfboards are powered by gravity, and gravitational potential energy is proportional to mass. Thus a heavier board has more mass and more inertia, in fact light and heavy boards both have the same ratio of mass to inertia, and thus have the same potential for acceleration, the actual result in practice being due to the actual thrust/drag ratio.

To put it bluntly, long heavy boards can accelerate as fast as, and faster than shortboards, it is really just a matter of design.

dunno what kind of surfing youre doing, but my surfboard is powered by waves not gravity. The reason most would say a shortboard is faster is that longboards generally travel along the wave in a straight line, or at least in mellow arcs. Whereas a shortboard NEEDS to be moving quickly in order to remain planing so is usually surfed up and down the wave a lot more generating speed from turns to keep the board going, therefore covering a greater distance along the same wave in the same time = faster average board speed
In terms of paddling however longboards are faster as the float and have less drag then shortboards at slow paddling speeds.
The fastest board tho has gotta be either a gun or a tow in board
not that any of this really helps the OP with his question

Hey Baja Fresk,

Not bad. But surfboards aren't displacement vessles when they are on a wave (just when they are floating or being paddled). They are a planing hull. By the tim ebuyoancy comes into effect the wave will pass you. Even on a longboard.

-doug

GowerCharger wrote:dunno what kind of surfing youre doing, but my surfboard is powered by waves not gravity.

Your board is powered by gravitational potential energy which is imparted to it when the wave lifts the board up. The wave does not push the board, the thrust which drives board and rider is in direct proportion to the combined mass of board and rider.

GowerCharger wrote:The reason most would say a shortboard is faster is that longboards generally travel along the wave in a straight line, or at least in mellow arcs. :

In my opinion most people consider that shortboards are faster because of the fact that the current state of longboard design creates remarkably slow boards due to the noseriding requirement, which entails boards which are generally slow and hard to handle at speed.

.

Without rider intervention I reckon long and short boards would go the same speed if all other variables were equal. Short boards would accellerate faster but have less momentum and so slow down quicker than longboards due to differences in mass and drag/friction/resistance.

But the biggest defining factor involved is the rider.

Think of it as going on a normal swing.


Without moving whilst you swing you have no part in helping it move, other than your mass being affected by gravity - so the swing will stop moving quite soon.
But when on a surfboard on a wave, what the surfer does massively affect the movement of the board - like if you stand on the wooden swing and pump whilst moving you can get the swing to go forever or even get the thing to go right over the top if you want .
This pumping action is the same as when a surfer pumps on a wave to go faster. It is quite simply using gravity to generate speed - you make yourself heavier on the bottom of the pump and lighter at the top. And it is this thing above all else such as size, weight of board, rail shape, rocker shape etc. that will affect the speed of a surfboard - unless we are talking about the rare situation of riding a 30ft big wave where you are just gunning it straight down the face, but even then you could gain an advantage by pumping when first taking off to accellerate faster.

So bassically I'm saying its the surfer that powers the board more than any other factor - long or shortboard. But gravity, wavepower, rail shape, rocker shape, tail shape, board mass etc. all have some affect but not as much as the rider.

All else being equal shortboards will not accelerate faster, that is a myth which is based on the mistaken idea that the thrust which drives a board is constant, regardless of board and rider weight, which it isn't, it is directly in roportion to rider and board weight. In many situations a heavy board will accelerate faster. .. .

if it helps, two skiers of 65 kilos, one on a pair of 165s and one on a pair of 185s, the one on 185s will go faster.

that is all.

All surfing speed conversations should ideally, in the future, in my opinion, include gps based speed readings. . . . if we all do it we will get an overall picture after a while of what different designs can do speed wise, and in what conditions.

Imagine if speed runs at Bonneville were not measured, it would be kind of confusing to figure out who was fastest, perhaps the amount of dust produced? Perhaps the logo? Or the fastest looking posture?

peds wrote:if it helps, two skiers of 65 kilos, one on a pair of 165s and one on a pair of 185s, the one on 185s will go faster.

that is all.

The skier on the longer skis must then be experiencing less friction, in spite of having potentially moe ski in contact with the snow. Would you say that the skier on shorter skis is slower because he can't carve long lines and produces friction with short turns? Or is it the case that if both skier just head straight downhill then the guy on longer skis is faster?