Author Topic: Wing Board Tail Rocker - Thoughts  (Read 32567 times)

Solent Foiler

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Re: Wing Board Tail Rocker - Thoughts
« Reply #30 on: June 06, 2022, 06:36:49 AM »
I think it's worth mentioning (and to give him some credit!) that Patrice has already put this design feature into nearly all of the 2022 Gong boards, having first appeared on last year's Lethal.
I'm 5'10", 66kg riding:
Swift Foil Boards custom 4'10 x 19.5" 35L
Gong Lethal 4'6 65L
Axis ART 799, 899, 1099, HPS 880 US & CS Adv fuse, 85cm mast
Gong Fluid L-S, XXL-S on 85cm and 65cm mast
Takuma RS 5.1, 4.3, 3.5

JohnnyTsunami

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Re: Wing Board Tail Rocker - Thoughts
« Reply #31 on: June 06, 2022, 10:47:39 AM »
DW, what have you found are the benefits to the Kalama tail for winging? Does it help starting or is it more for preventing speed loss for touchdowns? Kalama says elongating the flat section, but why go so narrow in the tail on the flat part?

I’m making a new board for a couple reasons, one of which is that mine likes to nosedive when pumping up in chop and jumping.

My use case is small foils that force my board to fully plane to get going. I feel the board plowing and with enough wind or max pumping it then goes “pop” I’m up and planing. A couple pumps on a plane and I’m fast enough to lift off (600 an 800 cm foils). My thesis is that a flat sheet of plywood is ideal, but I must make concessions for chop and touchdowns. More nose and a little tail rocker might do it. I just don’t see how the Kalama tail and chines would help?!



Dwight (DW)

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Re: Wing Board Tail Rocker - Thoughts
« Reply #32 on: June 06, 2022, 11:51:47 AM »
DW, what have you found are the benefits to the Kalama tail for winging?

The long story…..

It started with an opportunity to SUP his 5’2 x 28. The force to pull the blade was half any other SUP. Clearly the concept of allowing water to flow around, and off the back, with the least amount of drag worked.

Next was to try the concept winging. My thought was if less paddle force, then less wind force needed. In testing, the concept gets under motion earlier, AND more efficiently in choppy seas or confused currents. While the full wide planing bottom board, often needs a cleaner patch of water surface to get onto plane.

It is just an all around better board and easier to get on foil, even with fast foils.


Dwight (DW)

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Re: Wing Board Tail Rocker - Thoughts
« Reply #33 on: June 06, 2022, 11:56:42 AM »
I think it's worth mentioning (and to give him some credit!) that Patrice has already put this design feature into nearly all of the 2022 Gong boards, having first appeared on last year's Lethal.

To my eye, the Gongs have more in common with Kalama’s prototypes before he went full point at the back.

This version never went to production, but we see many others went to production with something similar.

https://www.instagram.com/p/CaD7517LJ2-/?igshid=YmMyMTA2M2Y=
« Last Edit: June 06, 2022, 12:08:20 PM by Dwight (DW) »

jondrums

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Re: Wing Board Tail Rocker - Thoughts
« Reply #34 on: June 06, 2022, 12:31:00 PM »
probably worth reading through this thread from 2 years ago

https://www.seabreeze.com.au/forums/Stand-Up-Paddle/Foiling/early-release-experimentation?page=1

This was from before Kalama hit on the iconic triangular tail concept.  On the second page there is an iteration that the original poster says is even better than the first try. 

As always, we are debating about topics that depend so highly on how we want to ride and which conditions we have - so it isn't surprising that we disagree often.

Solent Foiler

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Re: Wing Board Tail Rocker - Thoughts
« Reply #35 on: June 06, 2022, 04:42:44 PM »
I think it's worth mentioning (and to give him some credit!) that Patrice has already put this design feature into nearly all of the 2022 Gong boards, having first appeared on last year's Lethal.

To my eye, the Gongs have more in common with Kalama’s prototypes before he went full point at the back.

This version never went to production, but we see many others went to production with something similar.

https://www.instagram.com/p/CaD7517LJ2-/?igshid=YmMyMTA2M2Y=

I'm not saying they're identical, but there is more than a little resemblance between the tail on the KD board on the previous page, and the current tail of the Mint, for example. (If I was vaguely internet literate, I'd post some pics.)

They're all variations of a theme, which is not straight tail (that's is so 2021 🤪), but a displacement, low drag style. I'm curious which other production boards have also got that?
I'm 5'10", 66kg riding:
Swift Foil Boards custom 4'10 x 19.5" 35L
Gong Lethal 4'6 65L
Axis ART 799, 899, 1099, HPS 880 US & CS Adv fuse, 85cm mast
Gong Fluid L-S, XXL-S on 85cm and 65cm mast
Takuma RS 5.1, 4.3, 3.5

burchas

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Re: Wing Board Tail Rocker - Thoughts
« Reply #36 on: June 06, 2022, 06:04:14 PM »
They're all variations of a theme, which is not straight tail (that's is so 2021 🤪), but a displacement, low drag style. I'm curious which other production boards have also got that?

It certainly look that way. Maybe because Kalama has more clout or maybe his execution is just better that put him as the poster boy for this theme.

F-One incorporates something similar in some of their rocket boards, tail rocker however, is in all of their boards. I believe they got the right idea.
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Wave Chaser

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Re: Wing Board Tail Rocker - Thoughts
« Reply #37 on: June 06, 2022, 07:32:39 PM »
Things are changing so fast... We have all joked, "That's so 2021" about one thing or another in this crazy fringe sport.  But now that I purchased a 2022 Axis Froth (and by the way I think it's awesome) about a month ago and it's already outdated I guess I have to start saying my new beautiful board is so 2022?  The year is not even half over yet!  Will I be considered a Luddite if I am still using my 2022 gear later this year?
Age:  61
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Axis HPS 830, Ultrashort fuse, P350 tail, 86cm carbon mast, 45l Axis Froth board

Dwight (DW)

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Re: Wing Board Tail Rocker - Thoughts
« Reply #38 on: June 07, 2022, 03:27:22 AM »
Kalama is a straight tail. A planing flat out the back tail. A planing bottom that allows water to flow around the back to improve water release.

burchas

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Re: Wing Board Tail Rocker - Thoughts
« Reply #39 on: June 07, 2022, 07:23:40 AM »
I'm not subscribing to a certain magic shape or design attributes. Seems like the level of execution and implementation has more impact than a specific feature.
I've been riding SlingShot Wing Raider 4'10" x 27" @90L back to back Vs 2022 Fanatic 5'4"x26@95L. The WR pumps better and releases faster than the Fanatic.
stability is on par with the Fanatic comfortably schloging and knee starting from around 8knots and.

After seeing the 2022 Fanatic shapes on paper I thought they would perform like a Dwight board since the shape looks very similar.
Riding one of Dwight's FSM 4'10"x25.5@85L in marginal conditions, the difference in performance and stability over a Fanatic of a similar size was noticeable,
it's more on par with the Wing Raider. Two slightly earlier versions of the FSM didn't have quite the same magic.

The bottom of the Wing Raider is a double concave at the nose to a single concave all the way through the back. The wetted surface is under 4' long on 18.5" at the widest point
Looking at design features of the Wing Raider like a huge Kick tail and bottom concave, after spending enough time on the forums, you'd think the board literally sucks. Not the case.
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kwhilden

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Re: Wing Board Tail Rocker - Thoughts
« Reply #40 on: June 07, 2022, 10:36:05 AM »
Burchas... thanks for sharing the Wing Raider photos. 

It's an interesting design.  And helps confirm my theories about the physics going on here.  The key is to prevent large volumes of water from bending around big corners to fill a pressure void area.  Because the WR has a low angle step with low angle side corners, water can bend around easily, thus reducing drag in displacement mode.

I'm cracking the whip on my glasser as hard as I can, so I can get my board this week. 

My take on how to solve this problem is different than anything else I've seen.  In total of course, as I'm blending a number of ideas into one design.
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JohnnyTsunami

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Re: Wing Board Tail Rocker - Thoughts
« Reply #41 on: June 07, 2022, 11:26:09 AM »
To summarize, how I understand this, is it's about speed. Can we agree on the below 2 things?

1. ~ 0-6 mph - A more round canoe style is easier to accelerate at these speeds. Rounded edges everywhere or deep chines, tail kick, canoe stern. 

2. ~ 6-10mph - Hard edges in the tail area are better as the water will release cleanly at planing and near-planing speeds.

- A foil that gets going at 6mph has no benefit to #2 designs and should be simply #1.
- A foil that needs 10mph needs to get going should be #2 design, however, it will be a bit harder to get initial speed.

Foil takeoff speed varies between rider weights and foil characteristics.

My use case is that I'm not willing to give up planing ability to make things better at the low speed. I can feel things are hard to get going at low speeds on my #2 board, but if there is wind to take off, I can pump through this. However, I hate the feeling of getting within 1-2mph of foiling speeds pumping like mad and having my board "suck" at the tailkick. Maybe I'm just a fat guy with a tiny foil.  :P


Dwight (DW)

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Re: Wing Board Tail Rocker - Thoughts
« Reply #42 on: June 07, 2022, 02:16:01 PM »
To summarize, how I understand this, is it's about speed. Can we agree on the below 2 things?

1. ~ 0-6 mph - A more round canoe style is easier to accelerate at these speeds. Rounded edges everywhere or deep chines, tail kick, canoe stern. 

2. ~ 6-10mph - Hard edges in the tail area are better as the water will release cleanly at planing and near-planing speeds.

- A foil that gets going at 6mph has no benefit to #2 designs and should be simply #1.
- A foil that needs 10mph needs to get going should be #2 design, however, it will be a bit harder to get initial speed.

Foil takeoff speed varies between rider weights and foil characteristics.

My use case is that I'm not willing to give up planing ability to make things better at the low speed. I can feel things are hard to get going at low speeds on my #2 board, but if there is wind to take off, I can pump through this. However, I hate the feeling of getting within 1-2mph of foiling speeds pumping like mad and having my board "suck" at the tailkick. Maybe I'm just a fat guy with a tiny foil.  :P

You’re spot on. That’s why I didn’t make a Kalama clone a year ago. It wasn’t until a friend let me try his, then built one for me, that I discovered it does both in one. It’s a planing bottom, no tail kick. The pinned tail further reduces drag. The pinned back makes it work like it has rocker, without having it. It just does everything better. Easier for beginners, easier for racers. Try one.
« Last Edit: June 07, 2022, 02:41:41 PM by Dwight (DW) »

cnski

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Re: Wing Board Tail Rocker - Thoughts
« Reply #43 on: June 07, 2022, 06:18:43 PM »
JohnnyTsanami- How much you weigh? What 600 and 800 cm2 foils are you using?

surfcowboy

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Re: Wing Board Tail Rocker - Thoughts
« Reply #44 on: June 07, 2022, 07:51:07 PM »
Calling back to the "push volume down with less effort" (needed to clean that up lol.) The thing about pushing down is that you won't reduce the effort for the same volume, that's fixed. But your mind says that the angled wedge should require less effort at the same volume. This issue is that the wedge will always be less volume at comparable dimensions. 2 liters takes n amount of force to sink/displace.  This is what Pono was calling out. Additionally if they were the same volume you might assume the wedge might save effort because of drag but that would be minimal in 4-6" pump travel. Califoilia isn't wrong with that design or his feel. I'll bet it does pump easier than a blocky tail, because there's less volume back there.

Moving to Kalama best of both worlds. As usual DW explains it. Of course it's a #1 & #2 in one. The canoe shape gives you #1 low speed and the hard edges and bottom give you #2. Cool stuff.

I feel better now because people say all my boards are a big number 2. (I had to)


 


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