Ok , this could be a can of worms, and i may get 2 different schools of thought, but here goes.
So, if you had a board, board A, say 6’4’’ x 15n x 20.5 x 15 1/2’’ x 3’‘, and you took the template and cut it down 4’’ from the nose, and 2’’ from the tail, and ended up with a 5’10’’ x 16.5 x 20.5 x 16.75 x 3 ( board b ), which one paddles better, catches waves better etc. To my mind it would seem a shorter, wider, flatter board would paddle, and catch waves better, BUT, the longer board would have more surface area, and more foam, so, wouldn’t it float better, which would therefore help paddling, and wave catching??. The shorter board would also have a straighter outline.Im confused.
BTW, im not interested in how the board rides, just paddle, and wave catching ability. Oh, and the board would be for small waves up to head high only. Mainly beachies.
Here are my thoughts: Assuming we all have enough weight to submerge both boards below the surface when sitting/paddling…
There are a number of factors here, but they’re not all equal in terms of how they effect paddling/wave catching. I think volume is the most important factor here. More foam=more volume=more displacement=more boyant force. With that in mind, the greater the volume, the faster the board will get on top of the water when paddling into a wave.
The other factors still impact paddling, but matter much less than volume, because we’re talking about very low speeds. Added rocker on the longer board would have the second most impact… it should slow down the paddling, But I think the additional volume more than makes up for it. You lose a lot of volume chopping off 6 inches.
The other factors still impact paddling, but matter much less than volume, because we’re talking about very low speeds. Added rocker on the longer board would have the second most impact… it should slow down the paddling, But I think the additional volume more than makes up for it. You lose a lot of volume chopping off 6 inches.
I think those two boards would paddle pretty much the same. I did a test in boardcad and the difference between a 6’4 and 5’10 in volume is only .8 liter on a 31 liter board, 2%. Difference in area is pretty minimal too. Somehow I doubt you would notice this much, depending on how much you weight of course, what you had for lunch or if you did go for a pee before you went surfing. Given you take the same blank and don’t mess around too much with the foil and rocker (thin the ends from deck), the rocker that is in contact with the water when paddling into a wave is going to be pretty much the same on the same wave. When you paddle on flat water the board will be pretty much submerged. I don’t know which is going to push water more, the flip in the longer boards last few inches of nose or the submerged nose on the shorter one (or try to get the tip of the shorter above water and paddle it at an upward angle->drag).
So you’re saying the 2% is negligible at paddling speed… makes sense.
How much did the volume change in the nose vs. the tail?
My sense is that 2% out off the ends matters more than 2% out of the middle. Let’s say 1% of the total volume came off each end. Now consider the volume of the first and last foot of board. Now that 1% becomes 25% (?) of the volume in that area of the board. That’s a major change.
I don’t think that the changes matter that much at the nose/tail as long as the balance is the same. If your remove one liter at the nose and none at the tail you will need to paddle the board from further towards the tail to keep the nose from pearling which may have a very substantial effect on how the board paddles. If you remove the same volume at nose and tail, the balance stay the same and you don’t get those problems. Which is why I think foil is somewhat underrated for paddling power and one of the design concepts I keep screwing up…
You don’t specify whether it’s flat water paddling or into waves.
I won’t comment on the flat water except to say that wider boards are harder to paddle (but them I am comparing 22" wide 6’ to 23.5" wide 6’ boards). As you get narrower you probably notice the effect less.
If the tail on the shorter board is thicker, then it will catch waves easier. I think this is due to the tail lifting up the face, rather than sinking in it. Steeper angle = more pull down the face.
You might also find it’s easier to “rock the pendulum” on the shorter board - to move weight forward when paddling in with a similar result to the above idea.
End result is it depends on the wave more than the board. A longer board is probably better on a gently shelving wave, where the shorter board fits better with jacking waves
Can you run that program again and do nose/tail volumes?
I did it again and tried to do it more accurately to the board dimensions this time around. I was so puzzled by what I found that I had to check the volumes in akushaper too, wondering if there was a bug in boardcad volume calcualtions. They do show somehwat different volume, but the conclusion is still the same. The difference is roughly 0.1 liters at each end. What matters more for the volume is very subtle changes in the foil. It’s incredibly hard to match the same foil with these program to the accuracy required to really compare these volumes. A subtle change in the deck foil will make the shorter board the one with the highest volume. It would be better to use achimedes and dip 4 inches of nose of a board and see how much water it displaces.
Ever wondered why fish boards paddle so well despite the short length?
Interesting stuff guys. I have thought about making a round nose fish 4’’ shorter than what i ride now, but not sure about paddling etc. I’d probably widen the nose by an inch, and the midpoint by 1/2 or so. Just a bit worried about paddling it. Food for thought for sure
Volume distribution relative to rocker and the way your body composition is correlated has a huge affect on a boards paddling ability for me…
Im very very top heavy as I have chicken-hawk syndrome so I try to build my boards with more volume in the chest area and take alot out of the tail.
When I first started shaping I made two boards, a 6’6’’ with super flat tail rocker and a 16 inch tail, and another board, a 6’3" with probably 2.5 inches of rocker but all the volume in the belly/chest area. Both boards were made for the gulf, I made the 66 for myself and the other to sell and ended up trying the other one and i could paddle circles around the other board…
That second board was also a little flatter in the chest area with later nose entry but never had problems making drops no matter how late, you dont want your tail lifting and your nose sinking
Tail area/volume definetly means alot, but I think having the volume in the right places so when you make the drop you dont eat it is equally as important
For me, wider > thicker, easier to really plant the rail
Volume distribution relative to rocker and the way your body composition is correlated has a huge affect on a boards paddling ability for me…
Im very very top heavy as I have chicken-hawk syndrome so I try to build my boards with more volume in the chest area and take alot out of the tail.
IMHO the change in foil you do matter more than cutting of a couple of inches in length as far as volume go. On the other hand the lift from a flipped nose may not be negligible and may have a certain effect when paddling into a wave. I’ve said this before but I’ll say it again: foil is underrated for paddling performance. Pooling it in the center/just ahead of center is probably the safest bet, though I’m a bit puzzled about how little the center of gravity (balance point of the volume distibution) move when you change the foil on a thruster. Glad red brought up the subject about the board fitting into a wave as I’ve cut of 6" on a fish (6’8" → 6’2") and found that it now catch waves better…