Forums > Stand Up Paddle Foiling

Prone Board design progression is an illusion

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Created by TooMuchEpoxy > 9 months ago, 12 Oct 2021
TooMuchEpoxy
269 posts
12 Oct 2021 8:03PM
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I don't think board design is really doing much for us, expecially in the prone space, but its really easy to be tricked into thinking it is.

For someone doing agressive pumping, riding several times a week the loads and stress on a board are immense. I havent found any board thats actually good for long term use, including my own massively overbilt carbon and divinycell monstrosities. Everything starts to develop movement between the boxes and the front foot eventually, often with 0 visable damage. This means when you hop on the new freshie crazy bottom contour carbon fantastic OF COURSE IT FEELS BETTER. Everything i stiff fresh. In reality though nothing has changed and your back in the same spot 6 months later.

I'd argue that board builders should be focused on construction instead of shape and we need some kind of repetitive stress testing protocol to design a construction system that starts stiff and stays stiff. I want a board builder to tell me 5mm deflection at 150LB load on front pad after 10,000 cycles.

But then again what board builder wants to make a board that lasts longer?

I dont think this is much of an issue on SUP(board prevents any real pumping) and 0 issue winging.

eppo
WA, 9372 posts
12 Oct 2021 8:33PM
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So is this a feel thing or can you visibly see more flex in these boards you have had?

TooMuchEpoxy
269 posts
12 Oct 2021 8:39PM
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Its really hard to even see. The trick is to have someone wrench on the foil while standing on the board and put your hands on the bottom of the board around the tracks. You can really feel the movememnt if there is any.

frenchfoiler
498 posts
12 Oct 2021 11:22PM
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Maybe you should avoird Chinese board and look for professional shaper that master carbon construction.

TooMuchEpoxy
269 posts
12 Oct 2021 11:29PM
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I've seen both custom and production carbon boards with this issue. I'm confident there isn't anything on the market that would offer appropriate long term rigidity. If there was a custom shaper who was willing to make a firm gurantee about rigidity 6 months or a year later i'd be more than willing to buy that board. No custom builder would be willing to do that because nobody is building for long term rigidity.

Hdip
384 posts
12 Oct 2021 11:30PM
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Ask the progression project. He had big complaints about board construction early on. Box installs seem to have been fixed now.
boards make a huge difference.

TooMuchEpoxy
269 posts
13 Oct 2021 12:21AM
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I think things have been fixed in that its moved from visible destruction - water intrusion, cracks, delamination - to less visible destruction - flex and power loss. Its very hart to measure and i'd imagine even for him it just manifests in new boards feeling "better"

"Oho yeah this new design is fire, way better than the old one" when in reality the new one will be in the same position in 6 months.

Grantmac
1953 posts
13 Oct 2021 1:35AM
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Have you tried carbon I-beams rather than relying on the rails for vertical strength?

TooMuchEpoxy
269 posts
13 Oct 2021 2:06AM
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Current board is based on a box stringer. Started with a piece of divinycell cut to the outside width of the boxes, glued in the boxes, then fully wrapped that (wrapping from the bottom to all 4 sides in 2X 6ox carbon) so i have a 2"X 4 5/8" carbon box connecting the tracks to my front foot. Then i built the rest of the blank around that and shaped, vaccumed, with a single 6ox carbon all around Plus a 12ox uni deck patch connecting the back of the board to my front foot.

Core is 100% 3lb divinycell

Hdip
384 posts
13 Oct 2021 2:06AM
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Isn't this a problem with actual surfboards too? Team light glassing that pro's ride is basically disposable. I have a west coast foil club board that's all poly and never had an issue. Rode it solid for 2 years. I'm on a 52 foil co board now and it's holding strong a year later. I have to put my foot on the board and pull on my lift wings and slap them with my hand to get the fuse off the mast and I haven't felt any movement. I'll pay more attention next time I disassemble.

tomooh
275 posts
13 Oct 2021 3:24AM
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The small footprint of the mast base and the amount of leverage makes it hard . Something could be done with aluminium box section stringers connected to the mast and running through the standing area that wouldn't flex. Small alloy step ladders are pretty solid. Maybe too heavy but would be good to have a board that lasts. A lot is being asked of plastic fin boxes glued into foam and wrapped in fibreglass.

jondrums
154 posts
13 Oct 2021 6:19AM
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One thing I find very interesting structurally is that it is apparently pretty difficult to manufacture a mast due to the transition between the vertical mast and mounting "plate". See the NoLimitz thread for the founder of Project Cedrus talking about this. Then we have a tough time making boards stiff and strong enough connection between the deck and the dual boxes.

It seems to me that we are ripe for another step improvement. If we could come up with a way to bring back something like the tuttle connection - but somehow change it to allow adjusting it fore/aft like the boxes. I believe we could make the masts a bit lighter, and we could go to single stringer boards, which would also be lighter (likely). And we would smooth out the bottom obstructions for less drag during takeoff.

DarrylG
WA, 494 posts
13 Oct 2021 6:34AM
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Maybe it is time to try Tuttle box instead of tracks. Lighter and stronger. Still the preferred option for windfoil race boards, which have to deal with much higher loads

FoilAddict
95 posts
13 Oct 2021 8:24AM
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A Light carbon board is only really snappy for like 100 hours under a good rider. The best construction I've found for longevity is dual stringers attached to the boxes with additional reinforcement around the feet and boxes. Relying on the bond between composite and foam as little as possible is key.

paul.j
QLD, 3300 posts
13 Oct 2021 12:01PM
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Not sure what the problem is, I have over a year's use on my 4'5 full PVC molded sandwich prone board which i try and trash as much as possible and it's as good as the day i got it. I use it for both prone and on the ding from time to time plus i also use it as my Tow foil board and have run it over a few times with the ski. Light and tough as nail and still feels the same as the day i got it. www.oneoceansportsaustralia.com/shop/foil-prone-boards

We do spend a small fortune making our stuff though so maybe that's partly why

Grantmac
1953 posts
13 Oct 2021 10:10AM
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An adjustable tuttle would be possible IF you had a super strong box top that the foil mast fully engaged with then completely ignore the tapers. A mast with a flange could help too.

jonescb
NSW, 29 posts
13 Oct 2021 4:27PM
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Select to expand quote
Grantmac said..
Have you tried carbon I-beams rather than relying on the rails for vertical strength?


Carbon I-beam construction along each box works for me - no failures with my 85kg and my boards stay super stiff under foot.

hilly
TAS, 7195 posts
13 Oct 2021 4:35PM
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paul.j said..Not sure what the problem is,

+1, but possibly our foils flex and take some of the stress off the board or we are not aggressive enough riders to damage the boards we ride.

kobo
NSW, 1063 posts
13 Oct 2021 5:54PM
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On my 3rd prone board and I ride 5-7 times a week and never had a problem,hit the bottom a few times at full speed too.It does amaze me considering the forces involved that nothings happened . 1st board I had was a slingshot sandwich construction which seems stronger than the lighter fanatic boards I have now, I like the concept of the Armstrong boards with dual carbon stringers connecting to the box tracks and running up the board. I don't own one but it sounds good in theory.

TooMuchEpoxy
269 posts
13 Oct 2021 5:45PM
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I've seen other people not notice absoltely terrible flex. I myself had a board that looked like it was showing 0 movement, no flex no movement, where i could feel something was off and ended up trying a dozen different things before i realized it was the board

I gurantee someone out there is stalled in their progression becasue their board isn't transfering power right and they don't know because it still looks fine.

What i'm saying is this is a deficiency in the industry and what we need is standardized TESTING that board makers can subject their equipment to so we can have some real numbers around how different constructions behave over time. Deflection at load, deflection at load after 10,000 cycles. Some numbers here would be much more significant than weight or volume in how a board is going to preform on foil, expecially over time.

Maybe it starts simpler @paul.j maybe its just a matter of bolting an old board to a big piece of metal and seeing how much it moves when you stand on it like you would foiling

mcrt
611 posts
13 Oct 2021 6:32PM
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Don't know how you ride the proneboard but it must be really intense for a board to show any signs of mushiness or lack of energy transfer as you describe in 6 months.

I know we do not pump the wing boards much but i ride fast through chop,do millions of S-turns,DW, maneuvers etc...
In the last two years i have winged a lot, i do not think anybody can spend as much time on foil prone surfing for 6 months as i have winged in those two years.

If the construction was as bad as you say my Naish Hover Ultra should be falling to pieces,but it is good as new.None of the symptoms you describe.I just checked.

I watch all the Insta ripper vids and prone surfing is getting more aggressive every day but 90% is pretty mellow riding even at the top level.
As for the pumping, it is a very repetitive load but not that big, have no way to measure it but i do not think it is bigger than an upwind wingfoil run through 18kt chop.And wingfoil boards have a lot more inertia than prones.

www.instagram.com/p/CU8xaceDjVG/?utm_medium=copy_link

Not doubting your what you posted,if you say your boards degrade in 6months i believe you,but it does not fit my experience at all.

hilly
TAS, 7195 posts
13 Oct 2021 9:56PM
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TooMuchEpoxy said..
I've seen other people not notice absoltely terrible flex. I myself had a board that looked like it was showing 0 movement, no flex no movement, where i could feel something was off and ended up trying a dozen different things before i realized it was the board

I gurantee someone out there is stalled in their progression becasue their board isn't transfering power right and they don't know because it still looks fine.

What i'm saying is this is a deficiency in the industry and what we need is standardized TESTING that board makers can subject their equipment to so we can have some real numbers around how different constructions behave over time. Deflection at load, deflection at load after 10,000 cycles. Some numbers here would be much more significant than weight or volume in how a board is going to preform on foil, expecially over time.

Maybe it starts simpler @paul.j maybe its just a matter of bolting an old board to a big piece of metal and seeing how much it moves when you stand on it like you would foiling


Can you post a vid of you riding it will help us see why you are having issues.

eppo
WA, 9372 posts
13 Oct 2021 8:32PM
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mcrt said..
Don't know how you ride the proneboard but it must be really intense for a board to show any signs of mushiness or lack of energy transfer as you describe in 6 months.

I know we do not pump the wing boards much but i ride fast through chop,do millions of S-turns,DW, maneuvers etc...
In the last two years i have winged a lot, i do not think anybody can spend as much time on foil prone surfing for 6 months as i have winged in those two years.

If the construction was as bad as you say my Naish Hover Ultra should be falling to pieces,but it is good as new.None of the symptoms you describe.I just checked.

I watch all the Insta ripper vids and prone surfing is getting more aggressive every day but 90% is pretty mellow riding even at the top level.
As for the pumping, it is a very repetitive load but not that big, have no way to measure it but i do not think it is bigger than an upwind wingfoil run through 18kt chop.And wingfoil boards have a lot more inertia than prones.

www.instagram.com/p/CU8xaceDjVG/?utm_medium=copy_link

Not doubting your what you posted,if you say your boards degrade in 6months i believe you,but it does not fit my experience at all.





Select to expand quote
mcrt said..
Don't know how you ride the proneboard but it must be really intense for a board to show any signs of mushiness or lack of energy transfer as you describe in 6 months.

I know we do not pump the wing boards much but i ride fast through chop,do millions of S-turns,DW, maneuvers etc...
In the last two years i have winged a lot, i do not think anybody can spend as much time on foil prone surfing for 6 months as i have winged in those two years.

If the construction was as bad as you say my Naish Hover Ultra should be falling to pieces,but it is good as new.None of the symptoms you describe.I just checked.

I watch all the Insta ripper vids and prone surfing is getting more aggressive every day but 90% is pretty mellow riding even at the top level.
As for the pumping, it is a very repetitive load but not that big, have no way to measure it but i do not think it is bigger than an upwind wingfoil run through 18kt chop.And wingfoil boards have a lot more inertia than prones.

www.instagram.com/p/CU8xaceDjVG/?utm_medium=copy_link

Not doubting your what you posted,if you say your boards degrade in 6months i believe you,but it does not fit my experience at all.






Select to expand quote
mcrt said..
Don't know how you ride the proneboard but it must be really intense for a board to show any signs of mushiness or lack of energy transfer as you describe in 6 months.

I know we do not pump the wing boards much but i ride fast through chop,do millions of S-turns,DW, maneuvers etc...
In the last two years i have winged a lot, i do not think anybody can spend as much time on foil prone surfing for 6 months as i have winged in those two years.

If the construction was as bad as you say my Naish Hover Ultra should be falling to pieces,but it is good as new.None of the symptoms you describe.I just checked.

I watch all the Insta ripper vids and prone surfing is getting more aggressive every day but 90% is pretty mellow riding even at the top level.
As for the pumping, it is a very repetitive load but not that big, have no way to measure it but i do not think it is bigger than an upwind wingfoil run through 18kt chop.And wingfoil boards have a lot more inertia than prones.

www.instagram.com/p/CU8xaceDjVG/?utm_medium=copy_link

Not doubting your what you posted,if you say your boards degrade in 6months i believe you,but it does not fit my experience at all.



Nah big difference to using wing power than generating your own speed pumping the hell out
of a board back out to a wave. Your turns also can be more aggressive. Will see how the armie prone board goes i suppose. As hilly attested to there is inbuilt flex in the armie foil setup so maybe the attrition mushiness is not as noticeable. ?

TooMuchEpoxy
269 posts
13 Oct 2021 11:36PM
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oho i'm riding micro prone boards. The weight of a SUP is like a mass dapener, limiting the force and power you can put into that foil. I don't imagine this is much of a problem on SUPS

an example of some average riding for me www.instagram.com/p/CTDSJ1ylN6e/

kobo
NSW, 1063 posts
14 Oct 2021 6:24AM
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Select to expand quote
TooMuchEpoxy said..
I've seen other people not notice absoltely terrible flex. I myself had a board that looked like it was showing 0 movement, no flex no movement, where i could feel something was off and ended up trying a dozen different things before i realized it was the board

I gurantee someone out there is stalled in their progression becasue their board isn't transfering power right and they don't know because it still looks fine.

What i'm saying is this is a deficiency in the industry and what we need is standardized TESTING that board makers can subject their equipment to so we can have some real numbers around how different constructions behave over time. Deflection at load, deflection at load after 10,000 cycles. Some numbers here would be much more significant than weight or volume in how a board is going to preform on foil, expecially over time.

Maybe it starts simpler @paul.j maybe its just a matter of bolting an old board to a big piece of metal and seeing how much it moves when you stand on it like you would foiling


I don't think I've ever seen that kind of scientific testing standards applied anywhere in the surf industry ....first it has to be a big enough problem ,and you also have to get all the manufacturers to agree.It would be nice but unlikely,It's not like a safety issue in the car industry.

Piros
QLD, 6879 posts
14 Oct 2021 7:44PM
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I've never had any issue of board flex or crushing decks in my custom DC prones or JP Australia or Sunova boards . Plus no box failures . I don't ride production foil boards now due the fact we have been reducing volume and rail profile to engage the board off the wave and foam ball and release like a short board . JS make a beautiful board and you just need to watch Adam Bennett's just shred on them . The JS for bigger guys can be a bit hard to paddle in on and not super tough . So we built our our own DC customs on 2 pound foam and double layer of 6 oz top and bottom . This video is from 2.5 years ago on my old 4-4 and other than jet ski impacts and dropping it , it's still solid . ( I'm 90 kg )

I'm into about my 5th custom DC , I've got a 4-2 ,4-4 , 4-6 &. 4-8 . We have dropped the 2 pound foam and gone to the lighter version with the double layer 6 oz carbon wrap and are still solid . I have had more bottom high velocity bottom strikes than you have had hot dinners and never once a box failure .

martyman
WA, 314 posts
3 Nov 2021 12:31PM
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Select to expand quote
TooMuchEpoxy said..
Current board is based on a box stringer. Started with a piece of divinycell cut to the outside width of the boxes, glued in the boxes, then fully wrapped that (wrapping from the bottom to all 4 sides in 2X 6ox carbon) so i have a 2"X 4 5/8" carbon box connecting the tracks to my front foot. Then i built the rest of the blank around that and shaped, vaccumed, with a single 6ox carbon all around Plus a 12ox uni deck patch connecting the back of the board to my front foot.

Core is 100% 3lb divinycell


The Reality is with your hard/aggressive riding style and Large size you may just have to accept swapping boards every 6 months while you re-do the boxes

Kami
1566 posts
26 Dec 2021 7:10AM
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I hope those two stringers made of Divinicell 100 kg/m3 of 15mm thick would help hold the flexion between the Divincell 80kg/m3 block of the mast root and the 5mm cork deck reinforcement, glass lamination but the lam expensive carbon only around the mast root position.
I want the prone foil board of my son lasting his foiling beginnings for the little money I can spend.

Toomuchepoxy, would you put more carbon in this double stringers construction?






Ju_foil
NSW, 114 posts
26 Dec 2021 10:38AM
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Select to expand quote
TooMuchEpoxy said..
I don't think board design is really doing much for us, expecially in the prone space, but its really easy to be tricked into thinking it is.

For someone doing agressive pumping, riding several times a week the loads and stress on a board are immense. I havent found any board thats actually good for long term use, including my own massively overbilt carbon and divinycell monstrosities. Everything starts to develop movement between the boxes and the front foot eventually, often with 0 visable damage. This means when you hop on the new freshie crazy bottom contour carbon fantastic OF COURSE IT FEELS BETTER. Everything i stiff fresh. In reality though nothing has changed and your back in the same spot 6 months later.

I'd argue that board builders should be focused on construction instead of shape and we need some kind of repetitive stress testing protocol to design a construction system that starts stiff and stays stiff. I want a board builder to tell me 5mm deflection at 150LB load on front pad after 10,000 cycles.

But then again what board builder wants to make a board that lasts longer?

I dont think this is much of an issue on SUP(board prevents any real pumping) and 0 issue winging.


If you are a larger unit on a quest for ultimate stiffness maybe GoFoil Tuttle is your system.

I wonder if your needs are unique, Im 70kg and my Amos is about a year old and I think it's as stiff now as the day I got it but someone who is putting more load through their gear may be able to find the structural limit sooner.

TooMuchEpoxy
269 posts
26 Dec 2021 8:39PM
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Select to expand quote
Kami said..
I hope those two stringers made of Divinicell 100 kg/m3 of 15mm thick would help hold the flexion between the Divincell 80kg/m3 block of the mast root and the 5mm cork deck reinforcement, glass lamination but the lam expensive carbon only around the mast root position.
I want the prone foil board of my son lasting his foiling beginnings for the little money I can spend.

Toomuchepoxy, would you put more carbon in this double stringers construction?







@Kami Those divincell stringers are definately better than nothing but at the end of the day its just foam/woodfoam(cork). I think some kind of carbon is needed bridging the deck and bottom or transfering the forces to the rails. For the cork, its only going to make a real difference if there's laminate under it (cork sandwich).

@Ju_foil the thing that makes the tuttle great is the strong connection between the bottom and the deck. We're re-creating that with chinook boxes, building them into a carbon strcture thats tied into the bottom and deck laminates. The last board is holding up pretty well.

Also, as boards and foils get smaller having the ability to tune everything is essential. Mast placement + mast shim are essential tools for getting the most out of a setup, and often make the difference on something being rideable. Even same foil different wings, or same everything different conditions, great is often just a cm off unrideable. How we even rode gen 1 GoFoils with no tail shim, foil placement based on a guess, and no track is a mystery!

Kami
1566 posts
1 Jan 2022 9:53PM
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@TooMuchEpoxy


I found a design mystery similarity between finding the right cant and toe angle over the planning area of the surfboard vs the swing ability of the Foilboard and the shim angle of the foil itself. This mystery would be found out with the help of CAD as Shape3DX is Here below is the link to a video that explains the new features as
- NACA profile generator
- Import profile from .dat or .csv file
- Export to Xflr5 to compute foil Lift and Drag
of the Shape3DX software 9.1.1.6 version, which can help understand foiling parameters mystery even of the "basic" gen 1 GoFoils

?t=



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"Prone Board design progression is an illusion" started by TooMuchEpoxy