Is the volume really necessary?

eqKneelo · Post by **eqKneelo** » Mon Sep 29, 2014 8:10 am

Ships have sails or engines.

Waves are a power source that fluctuates. When that power source fades the board sink.

KNEEBOARDS DONT FLOAT MOST GUYS. They are sinking up to their chests when they sit on them.

So your analogy counters your point.
Boards do not float these guys in flat water. Mine now do.

And I wanna be a speed boat... Not a tug boat.

I'd like anyone who has an opinion about what does or doesn't float a surfer 6'4 and 220lbs to:

- list their height and weight
- submit video of these mythical thin boards that surf so well

Video doesn't lie.
I have plenty video of myself bogging on thin boards. Not pretty.

crox · Post by **crox** » Mon Sep 29, 2014 8:27 am

eq said - "Waves are a power source that fluctuates. When that power source fades the board sink."

If the power source fades to the point at which your board is fully underwater & still somehow gliding along, I salute you sir!
I feel that the drag from your knees & deckpad might have an overriding impact at that point!

you also said - "KNEEBOARDS DONT FLOAT MOST GUYS. They are sinking up to their chests when they sit on them."

Sometimes true, but that has nothing to do with what I'm talking about!

eqKneelo · Post by **eqKneelo** » Mon Sep 29, 2014 9:38 am

Let's blame beer and move on.

crox · Post by **crox** » Mon Sep 29, 2014 9:42 am

eqKneelo wrote:

Let's blame beer and move on.

Bryn · Post by **Bryn** » Mon Sep 29, 2014 11:53 am

Isn't it Rob Rennie who rode those super thick tailed beasts with almost a platform on the back?

Ok, so why do you want to discount paddling speed and ease of use when it's probably 90% of the time we spend in the water?? For ultimate performance to matter you need the ultimate wave on tap or its irrelevant.

I understand what you're saying but the ship analogy only works for a static object not a moving planing craft. I've been windsurfing a huge amount over the last few years and have sailed speed boards smaller than Big Tonys kneeboard in volume (my smallest board was 43cm wide and 53 litres)!! The key with getting planing is having enough power to get up enough speed to over take your bow wake and release, then as you say volume doesn't matter when up and running to a point. As soon as that power backs off yes you stop and sink. The more volume under you the longer that process takes and the more opportunity there is to find another power source (be it gust or swell or reform etc) to maintain that momentum and accelerate again. I think this holds true between sections or transitioning between turns even. You then have the opportunity to sink as much foam in to the water as possible and get more return from your effort to accelerate (but obviously it still needs to grip and not just cork out). Hence getting it right for your individual weight is invaluable.

I think looking at Slater et al is a moot point because they don't ride in a fixed position on their knees and require different parameters for their equipment to work.

Agreed that responsiveness and feel are increased but I don't think the performance gains would be huge by losing an inch of foam, just makes the other stuff we spend more time doing a whole lot harder! But I would definitely be keen to have a blade in the quiver for the right days at home for sure.

Aaah it's good to have a nice technical discussion again, been a while!!

Bryn · Post by **Bryn** » Mon Sep 29, 2014 11:54 am

On a side note if you really want sensitivity, i've been riding surf mats a huge amount the last year. Nothing else like it!!!!!!!! Learned a whole lot of new things about waves for sure.

crox · Post by **crox** » Mon Sep 29, 2014 12:19 pm

Bryn said - "I understand what you're saying but the ship analogy only works for a static object not a moving planing craft."
The point I was making was that the added volume only comes into effect when the ship is immersed....much as on the board.

& also - "As soon as that power backs off yes you stop and sink. The more volume under you the longer that process takes and the more opportunity there is to find another power source (be it gust or swell or reform etc) to maintain that momentum and accelerate again. I think this holds true between sections or transitioning between turns even. You then have the opportunity to sink as much foam in to the water as possible and get more return from your effort to accelerate"

I answered this above -

" If the power source fades to the point at which your board is fully underwater & still somehow gliding along, I salute you sir!
I feel that the drag from your knees & deckpad might have an overriding impact at that point!"

It is only at that point the added volume would come into play.

You also said -

"Agreed that responsiveness and feel are increased but I don't think the performance gains would be huge by losing an inch of foam"

But the crux of it is, we have established that we are not riding the optimum shape for performance but we are compromising it by preferring an easier paddle.

Quote Bryn - "Aaah it's good to have a nice technical discussion again, been a while!!

Full agreement!

maxb · Post by **maxb** » Mon Sep 29, 2014 4:52 pm

My turn my turn. I surfed at PV Indicator with Wes this last winter, some waxes were WAY over 20 on the faces and yes I mean Way over, any way Wes rode a 5'8' X 2" THICK CHIP OF A BOARD, Eric Peterson rode a 5'8"X 2.5" thick both of those boards were 22 wide I rode the big board of the bunch a 5'10" 2.25 thick 23 wide fish, we all got our share of the BOMBS and also took some floggings. All of the boards worked well on the waves ,but lacked in paddling, but more effort meant more waves, well worth it.
I have a Romo we have deemed the Barn Door 5'8" x 24x20 nose x19 tail
and 2.25 thick very flat rocker, flat bottom and v starts between set of fins.
boxes are at 12 and 18 to the rear of boxes, very soft rails, sq tail round nose, i'm over 200 and 6' tall, this is my go to grovei board, very loose, paddles like a dream,and glides over the flat sections, in my opinion width can take the place of thickness, but that is just my opinion.
I love all of the new designs Romr and I have collaborated on recently, and so have a few others who have them,
Max

red · Post by **red** » Mon Sep 29, 2014 7:01 pm

Nice to see a passionate discussion on design.

Other surfboard design forums suggest that surface area is an important factor (as has been suggested above).

Volume distribution is another issue. Not much impact from a flat water perspective, but for wave catching and wave riding it's important. When you talk about a 2 1/2" thick board, is this thickest point, lowest rocker or what? With a flat top stringer, thickest is going to be at rocker low point and then thin out fore and aft. Is it right for volume to be concentrated? Is that the right place for volume to be concentrated? My boards are 2 1/4 thick and thin railed, but they are 2 1/4 thick over 2' of the board, not 2" where the rocker bottoms out. Works for me, maybe not for you.

How about domed vs concave decks? With light EPS cores surfers found that they couldn't get the boards thin enough with sufficient rail, so shapers started flattening and then concaving the deck (concave adds strength). Some surfers preferred the lowered position, some not (I think that's your answer, Chris). You can push the volume by flattening the deck and then bringing it down at the rails without pushing overall thickness much.

Most know I'm a bean pole (6'2" 170lbs), so I won't get into big guy discussions. The point of my paragraphs above is to point out that there are more variables to consider than volume @1l/3kg. Most important of these are rocker, surface area and volume distribution.

Tom Linn · Post by **Tom Linn** » Mon Sep 29, 2014 9:05 pm

"As soon as that power backs off yes you stop and sink. The more volume under you the longer that process takes and the more opportunity there is to find another power source (be it gust or swell or reform etc) to maintain that momentum and accelerate again. I think this holds true between sections or transitioning between turns even. You then have the opportunity to sink as much foam in to the water as possible and get more return from your effort to accelerate"

I think Byrn makes a good point here. His comment explains the improvement in performance that Ed is focused on.

crox · Post by **crox** » Tue Sep 30, 2014 5:41 am

Tom/Bryn, It is only the volume in the water that will make a difference. Very little of the deck rail gets immersed even in mushy waves and I'm not advocating thinner rails. As I've said before, the game is over at the point when your knee is immersed & apart from kicking out I can never remember that happening. I would say if this section of rail was an issue then we would all have recessed deck pads to improve water flow in that area as this would be more effective.

If we are talking about burying the nose & then it popping up...I'm not advocating removing foam from there. We can't compare this situation to a windsurfer as that has an external power source...akin to us having a motor to lift us out of the situation.
I think the perception eq probably has is from thin boards with correspondingly thin rails & just overpowering the board.

This board - album_showpage.php?pic_id=24397&mode=prev#TopPic was only 2 1/4" thick but full rails, I sold it to a heavier guy because I could not bury the rail.[it worked great for him] It was low volume. picked up waves super easy & paddled great. [I am 6' & 175 lbs]

Red....volume distribution is another issue. I have had people hold a board upright by it's nose with it's rail facing me and wax lyrical over it's foil [stringer profile]. The only thing that is relevant from a hydrodynamic viewpoint [when we are riding] is how that foil is where it meets the rail & will interact with the water. We don't need that foil in the middle of the deck....& again if it were to come into play we wouldn't have a kneepad to interrupt flow! We are back to the dome on the deck being there to aid paddling.

Yes, concave decks are my preference, they also work well with the split flextails creating a corrugation that provides more twang in the tails. All my boards are EPS.

Max, great to have the info on the boards that you are surfing there & that you are prepared to trade paddling for performance.

eqKneelo · Post by **eqKneelo** » Tue Sep 30, 2014 7:21 am

in my opinion width can take the place of thickness

That's very true, Max... But what you also have working in your favor is your boards are very flat. The lack of rocker keeps your boards from plowing. (The original Lis Fish's were also very flat and fast.)
Once you introduce rocker to a board, you need to start stretching out the length, but then the volume and how it's foiled becomes key to allowing the rider to maintain speed and exploit the performance aspects of the rocker.

Crox- at 175lbs, think about how different the same waves energy is for you and I.

Not a 10ft wave... We're both hopefully going faster than slater

But a shoulder high wave is going to give you a much better push than it will give me. If on a scale from 1-10, the waves energy is only a 3, and I weight 45lbs more than you, of course you're going to be up and riding sooner and faster unless I have AT LEAST a proportional amount of foam.
(Yes, I could ride a short flat board, but I wouldn't be surfing the way I want.)

crox · Post by **crox** » Tue Sep 30, 2014 7:38 am

Ed, I fully agree you would need more foam & more so with big Tony.
That is not the point I was trying to make....but I can't think of any more ways to say it.

OceanTrends17 · Post by **OceanTrends17** » Tue Sep 30, 2014 12:55 pm

In the early to mid 80’s I had a surfboard sponsor so I was able to have a lot of boards made. I worked closely with my shaper to get the size and shape dialed in for my boards. I was 6’1” and 150 pounds then. I quit altogether in 1985. Last June, 28 years later, I returned to the sport. The same basic dimensions, with slight modifications since I now weigh 190 pounds, still work for my style of surfing.

While it was never really considered part of the equation back in the 80’s, high volume was not something I went for; it still isn’t. I attempt to go for the least amount of volume possible. As a result, Slow, mushy reform is something I struggle with in contests but honestly, I wouldn't surf in those conditions by choice anyway, so I have never ordered a board to perform in such.

My boards are basically the same shapes then as they are now, though I have gone from 12” noses and 2 ½” foam to slightly fuller noses (13-14”) and 2 5/8th” foam. All of my boards have a good rocker to them; the template being basically the same for all my boards. They are CNC shaped now, with all my designs stored on a computer program.

In smooth conditions I use boards with Brewer (low) rails and in choppy conditions I use boards with fuller, boxed, rails. The bottoms of all my boards are the same, hard rail transitions to a flat bottom with Vee through the tail; no channels or concave. The flat bottoms skim along the surface, the same principles as a hydroplane or skimboard. I have no issues “sinking” or bogging out unless the wave has no juice to it at all. One note: though I do surf beach breaks, I have my boards made for point and reef surf. All are epoxy glass over poly foam.

I have included video (for Ed) showing my boards in both fast and slow conditions. I don’t have much video to choose from but the basic illustration is that my boards all float about the same, they just perform differently, or force me to perform differently, based on the wave’s energy. I wouldn’t consider any of my boards (I have 7 at present) particularly high volume.

http://youtu.be/2EyoHFV-lco

hankj · Post by **hankj** » Tue Sep 30, 2014 1:25 pm

fwiw to me less volume surfs better and feels more alive but surfing is the total experience and I'll give up a little performance to be able to catch more waves and glide through the doldrums more easily, not bog at the top when a wave backs off on a snap, float higher out of the frigid water up here in WA, etc.

The board I'm on now is a scaled up knock off of a Romo that's the best surfing board I've ever been on, 2 inches longer and thickened up and flatter rocker under my chest when paddling. It's a high-performance shape but rides just a hair fun boardy because of its fattish rails and doesn't roll to a carve quickly or have that "tour pro" feel the Romo did, but in the end it catches a lot of waves and easily surfs well enough to get me a seat high enough in the pecking order around here to get left alone and not snaked. It feels about as good to surf as the Romo although it might not look quite as rad from the perspective of a spectator.

I think it's a style thing too - I tend to push whatever board into doing what I want it to by being more forceful, so whatever the loggy-er board lacks in radness mostly gets made up by force that's not displacing subtlety I don't have anyway. Plus I don't get to paddle often enough to get really strong like back in the day, so a little extra float is nice. It's good enough to keep the Romo in the bag almost every session even though the romo is a straight up wave murdering machine.