Forums > Windsurfing Foiling

Foiling, stress on the finbox and sail size

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Created by Francone > 9 months ago, 9 Feb 2020
Francone
WA, 291 posts
9 Feb 2020 12:35AM
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Hi
I windsurf but I am thinking of going hydrofoil. I can't afford a foil-dedicated board, though, just a regular shortboard.
Given the fact that some do not recommend, regular, non-dedicated boards because of the high stress generated by the foil, I'd like to know what are the real risks, keeping in mind that I'd sail in light winds ( 10-15 knts) and I am not a speed or acrobatics buff, as long as the board planes above the water.( not necessarily 80 cm, though..If I could plane 1 ft above it it would be great..)

I wonder if there is a correlation between the size of the sail ( =the power) and the stress in the finbox. If this is the case, to minimize the risk of breakage, I could perhaps rig the smallest possible sail, as long as it gives sufficient lift to raise the board above the water.

At 85 kg, I normally windsurf in light winds ( 12-15 knts) on my 11 ft Bic with an 8.0 or a 6.3 m2 sail. Below 12 knts it is almost mission impossible and this is why I was thinking hydrofoiling..

Here are my questions:

1.In these conditions, if a small sail really reduces the stress on the fin box ( which I am not too sure about, maybe an engineer can tell.) can I still expect to foil in light winds with a 5.0 or even less, given the fact that for foiling you can safely scale down the sail by two sizes?

2.As I understand, the lift of the foil is also in function of the wing's size. Can somebody give me the wing size range of the commercially available foils? What size is considered more " powerful"? If I am to shop for non-dedicated 2nd hand board, which one is recommended in terms of length, width, finbox, etc. Is a Deep Tuttle more recommended because of the depth of the box?

Thanks

Francone

segler
WA, 1623 posts
9 Feb 2020 2:26AM
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Keep searching. You will find quite a lot information and commentary about this.

When you talk about sail size, you seem to be talking about side forces on the finbox. Since fins do indeed lift horizontally, yes, sail size affects side forces on the fin. If you take this all the way up to 12.0 m sails and 70 cm fins on formula boards, yes, the side forces on the finbox are massive. Formula boards are well designed for this.

However, foiling is a different ballgame altogether. Of course, there is still some side force on the finbox since the foil mast (strut) acts as a huge fin. The much bigger force issue, however, is the cantilevering lift of the front wing. Look at a foil. The front wing is located anywhere between 10 inches to 18 inches in FRONT of the point where the mast plugs into the finbox. Ideally the front wing is at the midpoint between your feet. With the front wing lifting UP and the stabilizer lifting DOWN, the whole assembly wants to rock forward with the front wing as the fulcrum. This lever action is what lifts you, your rig, and board in front of the front wing. For a regular tuttle or deep tuttle finbox, this means the back screw is getting pulled in higher tension than the front screw. If you assemble a non-flanged foil into the finbox a bit loosely, and go out and foil it quietly and come back in, you will notice that the back screw is still really tight while the front screw is loose or even sticking up a bit, not even tight.

Flanged foil tops mitigate this effect by spreading the load over a bigger area. The Power Plate takes this extra area to the extreme. Also, track mounts (like you find on kite foil boards) spread the load widely.

So, to sum this all up, your concern about whether a finbox can carry foil loads has to focus on whether the finbox is strong enough to resist the forward-rocking cantilevering loads.

I believe most formula board finboxes are plenty strong enough for this, especially if they are built to have the deep tuttle finbox go all the way through the thick tail section and have the screws seat at the top of the deck, with no recesses. Boards with recessed screw tops worry me.

I do know that at least one custom foil board maker in Hood River uses ~12" long stringers fastened to both sides of the deep tuttle finbox to reinforce the cantilevering and keep the finbox from rotating forward when in flight. I have one of their boards, and I had them modify an old formula board a few years ago to include the stringers. I have no idea whether anybody else also uses the stringers. However, when a board is "foil-ready" it means that there is some kind of finbox reinforcement to prevent the finbox from rocking forward in flight.

I foil in the Columbia Gorge with hundreds of other windfoilers. I have yet to see, or even hear about firsthand, any finbox failures, even with pre-foil-ready boards that run deep tuttle, regular tuttle, or track mounts. Nobody foils on powerbox. I would worry about powerbox since they always have a single recessed screw and have a much smaller side area to bond to the board foam.

So, recommendations. If you are wanting to foil with an existing board and reduce the chances of finbox failure, use a board with a thick tail section and deep tuttle finbox where the screw heads are stopped on the top deck. No recesses, no powerbox. Use big fender washers on the screw tops to spread the screw loads. Choose a windfoil that includes a flange on the top such that the flange rests on the bottom deck to spread the loads. Slingshot aluminum, some models of AFS, some models of Moses, and some others, feature flanges. The Power Plate mates with Slingshot aluminum and not only spreads the loads a lot, but also lets you tune the balance by moving the mast fore and aft.

segler
WA, 1623 posts
9 Feb 2020 2:51AM
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Sorry, I did not address your other question. You are 85 kg. I also am 85 kg.

Front wing area is a HUGE point of discussion in this sport. Let me tell you what works and what a lot of windfoilers like to use.

For me the ideal front wing area is 950 to 1050 cm2. My 779 cm2 wing requires me to maintain aggressive speed to keep it working. That's OK, but if I want to relax, it is too sporty. My 940 cm2 wing is pretty much goldilocks; I can go to sleep on it, or still push it hard.

My 1120 cm2 wing is a real wonder for lightwind and low speed foiling. Very relaxing to use, but limited on top speed. In fact, it lifts so well, that I can stall the strut and get classic spinout while still flying. It is fun to do this on purpose.

A really really popular wing that offers excellent lift for heavy guys as well as reasonable speed range is the Slingshot i76. It sits in the range of i68, i84, and i99. Look up the areas. The i76 has more area than my wings, but there is a reason why it is so popular, even in the Columbia Gorge.

Francone
WA, 291 posts
9 Feb 2020 5:11AM
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Thanks Segler!
Your reply is a gold mine of information!
The only thing which I am not too enthusiastic about is foiling 70 cm above the water.
Can the above water clearance of the foil be controlled?
Basically there are 3 reasons that make me a bit unconfortable:
1. Falling from 70 cm may be more hazardous
2. I still like the contact with the water
3. Shallow waters.
Where I sail I have to tread water for close to 100 ft before the water is deep enough. I wonder how resilient are the carbon and aluminum when the foil hits the bottom or, God forbid, rocks.
But perhaps all these worries will disappear once I try !
Anyway this is something that is for me decide. For the rest, I'll keep in mind your suggestions.

Thanks

Francone

segler
WA, 1623 posts
9 Feb 2020 2:06PM
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Let me try to answer these.

1. First, being up above the water is frightening ONLY AT FIRST, but then actually desirable later once you get the muscle memory dialed in and get things figured out. You will at first be shocked at the QUIET once you are not slapping the water. Yes, controlling your height above water is pretty much the whole point of foiling. It will take practice. You will grow to like it. A lot. Yes, you will fall many times while you are learning. Falling even from a meter up in the sky is not so bad. Big splash, so what. Do stay off the harness while you are learning. Do add some padded nose protection on your board.

2. Pretty soon you will actually hate contact with the water. Noisy, slappy, hard on the knees and teeth, not cool. Flying is where it's at.

3. Shorter masts are definitely a good thing for shallow water. In the everywhere-shallow waters of Florida I started off with a 61 cm mast, then quickly went to a 76 cm mast, but now ride only a 90 cm mast. Short masts cause breaching too easily once you decide you like the flight and the quiet. Taller is better, to a point. That point is the ground under water.

You definitely want to avoid running aground, especially with any kind of speed.

I think you will find that you will want to foil only in sufficiently deep water. In Florida I have found a nice pool about 1 mile x 1 mile and deep enough to be over my head even at low tide. Good, secure, deep water. I don't even like to foil anywhere else.

Start with a floaty board, and just uphaul. If you can waterstart, your sail is too big for learning to foil. The small sail is what makes it easy to forget the harness.

By the way, during your learning curve, there is nothing wrong with flying really low, so that your board ticks the tops of waves. This tends to stabilize the board to keep it flat and level while you are figuring out foot control. You can do this with ANY length of mast I call this training wheel mode. It won't be long before you are lifting higher and staying above the wave tops. It's all so so so QUIET up there.

Francone
WA, 291 posts
10 Feb 2020 1:24AM
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segler said..
Let me try to answer these.

1. First, being up above the water is frightening ONLY AT FIRST, but then actually desirable later once you get the muscle memory dialed in and get things figured out. You will at first be shocked at the QUIET once you are not slapping the water. Yes, controlling your height above water is pretty much the whole point of foiling. It will take practice. You will grow to like it. A lot. Yes, you will fall many times while you are learning. Falling even from a meter up in the sky is not so bad. Big splash, so what. Do stay off the harness while you are learning. Do add some padded nose protection on your board.

2. Pretty soon you will actually hate contact with the water. Noisy, slappy, hard on the knees and teeth, not cool. Flying is where it's at.

3. Shorter masts are definitely a good thing for shallow water. In the everywhere-shallow waters of Florida I started off with a 61 cm mast, then quickly went to a 76 cm mast, but now ride only a 90 cm mast. Short masts cause breaching too easily once you decide you like the flight and the quiet. Taller is better, to a point. That point is the ground under water.

You definitely want to avoid running aground, especially with any kind of speed.

I think you will find that you will want to foil only in sufficiently deep water. In Florida I have found a nice pool about 1 mile x 1 mile and deep enough to be over my head even at low tide. Good, secure, deep water. I don't even like to foil anywhere else.

Start with a floaty board, and just uphaul. If you can waterstart, your sail is too big for learning to foil. The small sail is what makes it easy to forget the harness.

By the way, during your learning curve, there is nothing wrong with flying really low, so that your board ticks the tops of waves. This tends to stabilize the board to keep it flat and level while you are figuring out foot control. You can do this with ANY length of mast I call this training wheel mode. It won't be long before you are lifting higher and staying above the wave tops. It's all so so so QUIET up there.



Thanks again for your invaluable information.
I still have a couple of questions .

1.I may have a good deal on a NP RS One foil.
This foil comes with a DeepTuttle head. If I am to buy a Powerplate ( Deep Tuttle) to reinforce the finbox, of the new board , as you suggested in your earlier reply , is the NP foil Deep Tuttle head ( the male ridge) designed to slide into the Powerplate Deep Tuttle female housing and the whole assembly will then finally slide and be bolted onto the board's finbox slot ( Deep Tuttle) ?
To do so, one has to be smaller than the other.
I Don't know what are the standard measurements, because neither the NP Foils site nor the Powerplate site give information on this, but I want to be sure before buying.
2. The NP mast is 85 cm. Considerably longer than I was envisaging, as a novice.
I take note of your encouragement to go long mast. I'm sure I'll get used to it.. I was wondering, though, if , at least in the beginning, the cruising height above the water can be decreased by adjusting the tilt and angle of attack of the foil's front wing ( if such an option exists..), or by the body's position on the board or by rigging the smallest possible sail that allowed lift in light winds or by all of the above .
May be a small sail will depower the foil enough to keep the board lower than 80 cm above the water.
Even with a small sail, the NP foil should have the necessary lift power, because the front wing has a 720 mm wingspan, corresponding in my estimate, to probably more than 1000 cm2 area.
Thanks for the comments

Francone

segler
WA, 1623 posts
10 Feb 2020 2:18AM
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I might have said some things that are confusing.

1. The Power Plate does not reinforce the finbox. Instead, it offers a huge rectangular flange that spreads the load. It comes with a choice of tops for tuttle, deep tuttle, or powerbox. Those tops plug into the finbox as normal. But here's rub: you have to attach the foil mast (strut) to the bottom of the Power Plate. The Power Plate acts just like a track mount like some boards (such Naish and most kiteboards) offer. If your foil has a track-mount top, you can attach it directly to the Power Plate. Some foils offer track-mount tops as options to the standard deep tuttle tops. All of those can be attached to the Power Plate directly.

Slingshot, for example, offers optional tops, either track-mount or deep tuttle. To use a Power Plate with Slingshot, or any other brand, you opt for their track-mount top. Thus, the Power Plate takes the place of the stock Slingshot smaller-flange deep tuttle top. You can find more information about the Power Plate online.

chinooksailing.com/products/powerplate-windsurf-foil-plate-coming-soon?variant=5236961968165

If you are looking at a RS One foil with deep tuttle top, and if you have a board with a deep tuttle finbox, you are good to go. Plug and Play. No need for a Power Plate.

A big unsung benefit of the Power Plate is the fore-and-aft adjustability to achieve balance. If you have a board with the deep tuttle finbox too far aft (like my old formula board) the Power Plate allows you to "move" the mast further forward to get the wing closer to the balance point (midpoint between front and back feet to start with). Attachedbelow is a photo of a Power Plate for a board with a VERY aft finbox.

2.. No, you don't want to be messing with the tilt of the front wing to try to control height. Instead, you control height with your body and feet. You will get the hang of this pretty quickly. Yes, some foils offer adjustable tilt of the REAR STABILIZER. Just go with what you have and learn to foil with it. Don't overthink this. Just do it.

Sail size is only a very indirect control of ride height. Yes, sail size does impact the mast base pressure, but that is only one of the many variables in balancing your gear. More about balancing below.

At your weight you need only two sails to learn the sport: 6.5 and 5.0. Maybe a 7.5 for really light winds. Don't worry yet about cam versus no-cam and all that stuff. Yes, you use smaller sails for foiling than you did for finning. About 2 sq m smaller most of the time. My go-to sail is a 6.4, which is the sweet spot size for 15 mph winds. If it is too windy for a 5.0, just watch from the beach until you get better at it. You will get better at it.

Now about balance. You must balance your gear or you will struggle mightily. The goal is to get the front wing at the midpoint between your feet, and then set the sail mast base at something like 42" in front of the front screw. Then fine-tune from there. I made a youtube about this a couple years ago. Note, if your foil mast is 90 degrees up from the fuselage, this measurement is easy without the right-angle tool. I needed the tool because my mast is raked forward.



Good luck. Welcome to the sport. We are always glad to infect others with our disease.




Paducah
2546 posts
10 Feb 2020 4:08AM
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Francone said..
Even with a small sail, the NP foil should have the necessary lift power, because the front wing has a 720 mm wingspan, corresponding in my estimate, to probably more than 1000 cm2 area.


Pretty sure the RS One wing is going to be around 800 cm2 (or less) given when it came out. That was the common size for a racing wing then. The 1000's didn't become prevalent until the following year. I tried looking up the actual number and NP makes it almost impossible to find. I saw one in the flesh back then and my impression then was that it was noticeably smaller than the 970ish lightwind wing I was using most of the time then.

If you want a lifty, easy to ride foil for using a small sail in minimal wind at your beginning skill level, you'll benefit from more area. If you want to stay with Pryde, the 2020 Glide series are good value. The 19's have a shorter mast which, as Segler suggests and I would agree, you will outgrow. Short masts feel like comfortable training wheels your first sessions but they become very frustrating as you constantly foil out unless you are in the absolute flattest of water. I know there are some screaming deals on the older Pryde foils now in NA - just make sure they fit your needs and you aren't just saving pennies and not getting what is best for you long term.

Francone
WA, 291 posts
10 Feb 2020 4:28AM
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Select to expand quote
segler said..
I might have said some things that are confusing.

1. The Power Plate does not reinforce the finbox. Instead, it offers a huge rectangular flange that spreads the load. It comes with a choice of tops for tuttle, deep tuttle, or powerbox. Those tops plug into the finbox as normal. But here's rub: you have to attach the foil mast (strut) to the bottom of the Power Plate. The Power Plate acts just like a track mount like some boards (such Naish and most kiteboards) offer. If your foil has a track-mount top, you can attach it directly to the Power Plate. Some foils offer track-mount tops as options to the standard deep tuttle tops. All of those can be attached to the Power Plate directly.

Slingshot, for example, offers optional tops, either track-mount or deep tuttle. To use a Power Plate with Slingshot, or any other brand, you opt for their track-mount top. Thus, the Power Plate takes the place of the stock Slingshot smaller-flange deep tuttle top. You can find more information about the Power Plate online.

chinooksailing.com/products/powerplate-windsurf-foil-plate-coming-soon?variant=5236961968165

If you are looking at a RS One foil with deep tuttle top, and if you have a board with a deep tuttle finbox, you are good to go. Plug and Play. No need for a Power Plate.

A big unsung benefit of the Power Plate is the fore-and-aft adjustability to achieve balance. If you have a board with the deep tuttle finbox too far aft (like my old formula board) the Power Plate allows you to "move" the mast further forward to get the wing closer to the balance point (midpoint between front and back feet to start with). Attachedbelow is a photo of a Power Plate for a board with a VERY aft finbox.

2.. No, you don't want to be messing with the tilt of the front wing to try to control height. Instead, you control height with your body and feet. You will get the hang of this pretty quickly. Yes, some foils offer adjustable tilt of the REAR STABILIZER. Just go with what you have and learn to foil with it. Don't overthink this. Just do it.

Sail size is only a very indirect control of ride height. Yes, sail size does impact the mast base pressure, but that is only one of the many variables in balancing your gear. More about balancing below.

At your weight you need only two sails to learn the sport: 6.5 and 5.0. Maybe a 7.5 for really light winds. Don't worry yet about cam versus no-cam and all that stuff. Yes, you use smaller sails for foiling than you did for finning. About 2 sq m smaller most of the time. My go-to sail is a 6.4, which is the sweet spot size for 15 mph winds. If it is too windy for a 5.0, just watch from the beach until you get better at it. You will get better at it.

Now about balance. You must balance your gear or you will struggle mightily. The goal is to get the front wing at the midpoint between your feet, and then set the sail mast base at something like 42" in front of the front screw. Then fine-tune from there. I made a youtube about this a couple years ago. Note, if your foil mast is 90 degrees up from the fuselage, this measurement is easy without the right-angle tool. I needed the tool because my mast is raked forward.



Good luck. Welcome to the sport. We are always glad to infect others with our disease.





Great, as usual , especially the Youtube video.
I am glad to hear that If the foil has a Deep Tuttle head, then I don't need a Powerplate!
Good! I understood you saying that on an older generation board, a flange is needed in order to better distribute the stress on the finbox and thus avoid breaking it, or worse, ripping through the upper deck..This is why I thought that a Powerplate is always necessary.
As to the sail, I have an 8.2 Hot Maui, Dacron and an oldish, but still functional NP Garda 6.2. I hope the 8.0 Maui Hot Sail will get me off the hook when winds are really low, around 10 knts, as is often the case here. If an 8 m2 works on a regular fin board, it should work even better for foiling, taking into account the two sizes sail downsize in foiling.

Also glad to hear that I can control the height , if not with a smaller sail size, with the body position.
I don't know if using the harness and the footstraps is as necessary, or at least recommended, as it is for regular fin windsurfing. Maybe not, because from what I see, you have to move around a lot to control the height and the balance of the foil. I'll have to learn it...Not as easy for somebody born around the end of WW2, (but still, I must say, with a lot of..ammunition. It won't last forever, though, ( which is an understatement! ), but winsurfing will certainly help..

Thanks again

Francone

Francone
WA, 291 posts
10 Feb 2020 4:59AM
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Paducah said..


Francone said..
Even with a small sail, the NP foil should have the necessary lift power, because the front wing has a 720 mm wingspan, corresponding in my estimate, to probably more than 1000 cm2 area.




Pretty sure the RS One wing is going to be around 800 cm2 (or less) given when it came out. That was the common size for a racing wing then. The 1000's didn't become prevalent until the following year. I tried looking up the actual number and NP makes it almost impossible to find. I saw one in the flesh back then and my impression then was that it was noticeably smaller than the 970ish lightwind wing I was using most of the time then.

If you want a lifty, easy to ride foil for using a small sail in minimal wind at your beginning skill level, you'll benefit from more area. If you want to stay with Pryde, the 2020 Glide series are good value. The 19's have a shorter mast which, as Segler suggests and I would agree, you will outgrow. Short masts feel like comfortable training wheels your first sessions but they become very frustrating as you constantly foil out unless you are in the absolute flattest of water. I know there are some screaming deals on the older Pryde foils now in NA - just make sure they fit your needs and you aren't just saving pennies and not getting what is best for you long term.



I suppose you are right. May be I had overestimated the area.
The NP specs for the RS One give a 720 mm wingspan. Looking at the photo of the foil on their site, the maximum width of he wing is about 70 mm or approximately 21% of the photo wingspan. Applying this ratio to the real 720 mm, we get a maximum real width of 150 mm. This would give a 1080 cm2 area for a rectangle, but the wing is tapered, therefore the areashould be 800-900 cm2. f
It may not give an optimal lift and maybe you or somebody else can comment on this, but the price is good and it may be it is a good buy for a beginner. I'll make up with larger sails .

Francone

Paducah
2546 posts
10 Feb 2020 6:55AM
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Select to expand quote
Francone said..


Paducah said..




Francone said..
Even with a small sail, the NP foil should have the necessary lift power, because the front wing has a 720 mm wingspan, corresponding in my estimate, to probably more than 1000 cm2 area.






Pretty sure the RS One wing is going to be around 800 cm2 (or less) given when it came out. That was the common size for a racing wing then. The 1000's didn't become prevalent until the following year. I tried looking up the actual number and NP makes it almost impossible to find. I saw one in the flesh back then and my impression then was that it was noticeably smaller than the 970ish lightwind wing I was using most of the time then.

If you want a lifty, easy to ride foil for using a small sail in minimal wind at your beginning skill level, you'll benefit from more area. If you want to stay with Pryde, the 2020 Glide series are good value. The 19's have a shorter mast which, as Segler suggests and I would agree, you will outgrow. Short masts feel like comfortable training wheels your first sessions but they become very frustrating as you constantly foil out unless you are in the absolute flattest of water. I know there are some screaming deals on the older Pryde foils now in NA - just make sure they fit your needs and you aren't just saving pennies and not getting what is best for you long term.





I suppose you are right. May be I had overestimated the area.
The NP specs for the RS One give a 720 mm wingspan. Looking at the photo of the foil on their site, the maximum width of he wing is about 70 mm or approximately 21% of the photo wingspan. Applying this ratio to the real 720 mm, we get a maximum real width of 150 mm. This would give a 1080 cm2 area for a rectangle, but the wing is tapered, therefore the areashould be 800-900 cm2. f
It may not give an optimal lift and maybe you or somebody else can comment on this, but the price is good and it may be it is a good buy for a beginner. I'll make up with larger sails .

Francone



A good price for a foil is one that assures you success as a beginner and allows you to grow your skills as you progress.

We've learned a lot since the first generation NP foils came out almost three years ago. If you lived in a place where you consistently had 15-20 knot winds, this would be a different conversation. There are a bunch of affordable foils out there that will give you a much higher chance of both having fun and being successful: the Starboard Freeride (1100cm2) to the range of Slingshot (i76/i84etc) and NP Glides just to name a few.

The most expensive foil is the one that leaves you frustrated and not achieving your goals no matter how little it cost.

Relevant: marseille.glissattitude.com/blog/windfoil-test-np-rsflight-et-glide.html (the comments below the review are helpful, too)

segler
WA, 1623 posts
10 Feb 2020 8:28AM
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Back to boards with deep tuttle finboxes. Most are just fine as is. No Power Plated needed--unless you want to move the strut fore and aft to compensate for a not-optimized finbox position. My Florida formula board has a nice strong deep tuttle finbox, but it is too far aft. I use the Power Plate to move the strut forward, as the photo shows.

Footstraps. You might want to start out with zero straps. You will be stepping around on the board to "hunt" for the best position. Once you have found that position, you can (hopefully) mount the straps at that position. Even then, lots of foilers use ONLY the front straps, and leave the rear straps off altogether.

Foiling involves a lot of trial and error, along with lots of crashes. Once you have things balanced, or nearly balanced, the learning curve with trial and error is greatly shortened. Getting it balanced is really important, even before you hit the water the first time. Case in point: if you buy a foil at Sailworks, they have you assemble it, and show you how to balance it right there in the shop before you leave. They don't want their customers to struggle needlessly.

boardsurfr
WA, 2335 posts
10 Feb 2020 10:33PM
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While there is no information about the area of the RS:One to be found, the width, chord length, and outline are very similar to the NP Flight AL, which has an area of 801square centimeters. That's a lot less than the areas on more modern freeride foils, like the 1534 cm2 for the Slingshot i76. Fanaticsuggests the Flow 1250 for light wind and beginners, and calls the smaller 900 "our new freerace wing". Unless you routinely get 15 knot winds or want to get into foil racing, 800 cm2 foils are a bad choice. I've seen one beginner struggle to get going on a foil this size when others on i76 foils had no problems going. Even some of the advanced foilers who tried his foil could not get it to fly in the lighter winds.

Paducah
2546 posts
11 Feb 2020 12:25AM
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boardsurfr said..
While there is no information about the area of the RS:One to be found, the width, chord length, and outline are very similar to the NP Flight AL, which has an area of 801square centimeters. That's a lot less than the areas on more modern freeride foils, like the 1534 cm2 for the Slingshot i76. Fanaticsuggests the Flow 1250 for light wind and beginners, and calls the smaller 900 "our new freerace wing". Unless you routinely get 15 knot winds or want to get into foil racing, 800 cm2 foils are a bad choice. I've seen one beginner struggle to get going on a foil this size when others on i76 foils had no problems going. Even some of the advanced foilers who tried his foil could not get it to fly in the lighter winds.


The Glissattitude review linked above mentions a noticeable difference between the RS:One and the '19 Flight Al. I'd be willing to suggest that it's [RS:One] at best 750. Not all 800s are a bad choice - the AFS F700 and Starboard 800 are quite reasonable under someone 75kg or less. Not for super light wind but not bad for 10 and above.

Otherwise, I agree with you generally especially since the OP weight 85 kg.

segler
WA, 1623 posts
11 Feb 2020 3:04AM
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I concur with the above two comments. I am also 85 kg. I started with the AFS-2 with the F700 wing (779 cm2). It was something of a struggle. I had to keep it going pretty hard to keep it flying. For a newbie, this was challenging. This wing in shown in the youtube above.

When I got the F800 wing (1120 cm2), it was a MAJOR game changer. All of sudden I could make nice easy long cruises at manageable speeds and power levels. In Florida I have a foil with 1100 cm2 (see photo above). It also is an easy riding cruiser. These wings fly nicely at 15-18 mph boat speed.

For the OP's 85 kg, I strongly recommend a wing area of 1100-1500 cm2 to learn on. If you go with Slingshot, there is no better starter wing than the i76 at ~1534 cm2. Since Slingshot is modular, you can go with smaller, or even bigger, wings later as you get better. Many, many successful new foilers are doing exactly this. The i76 is very popular in the Seattle area, AND in the Columbia Gorge.

gorgesailor
604 posts
11 Feb 2020 3:58AM
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segler said..
I concur with the above two comments. I am also 85 kg. I started with the AFS-2 with the F700 wing (779 cm2). It was something of a struggle. I had to keep it going pretty hard to keep it flying. For a newbie, this was challenging. This wing in shown in the youtube above.

When I got the F800 wing (1120 cm2), it was a MAJOR game changer. All of sudden I could make nice easy long cruises at manageable speeds and power levels. In Florida I have a foil with 1100 cm2 (see photo above). It also is an easy riding cruiser. These wings fly nicely at 15-18 mph boat speed.

For the OP's 85 kg, I strongly recommend a wing area of 1100-1500 cm2 to learn on. If you go with Slingshot, there is no better starter wing than the i76 at ~1534 cm2. Since Slingshot is modular, you can go with smaller, or even bigger, wings later as you get better. Many, many successful new foilers are doing exactly this. The i76 is very popular in the Seattle area, AND in the Columbia Gorge.


I would agree except if you consider Francone's post history which should give you a pretty good idea of his current ability level & equipment preference. He is not used to sailing powered as most short board sailors would consider it. So the 1-2 sail sizes lower does not apply in his case - IMO. I would say he definitely need the biggest wing he can get hold of... such as the Slingshot i99 or at least 84 or the Starboard Supercruiser, NP Glidewind L or similar low aspect style... I very much doubt he would outgrow any of those wings as I don't think he want's to run the sail power needed to do so... just IMHO.

segler
WA, 1623 posts
11 Feb 2020 5:19AM
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I can't really disagree. However, I think the i84 and i99 are a bit of overkill. With those you get lift at a whole 1 mph slower than with the i76.

The OP can't really go wrong with any of those three, if he goes with Slingshot.

boardsurfr
WA, 2335 posts
12 Feb 2020 12:23AM
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For your entertainment, here's what the OP wrote on the US forum:

"Anyway, there is always a good amount of subjectivity in the ratings.
The question is not whether the NP RS One is good or bad in absolute terms, but rather how well it meets the diverse needs and abilities of different windsurfers, including me..
I know NP is a very reputable company and my only worry, as beginner, is the challenge of learning how to foil...

I know there might be better choices" by the book" and I value as usual the opinion of experts in this Forum or elesewhere , but unfortunately my choices are limited by my budget. In the end, my real choice is between giving up foiling because of the high cost, or taking a chance...For a $ 400 ( CAD ) investment in a 2nd hand NP RS One foil, I think it is worthwhile. I am prepared to regret my choice, but I hope I won't...

This is in the end how my windsurfing story has unfolded so far: caught in the shortboard and planing craze and unable to enter this " paradise" partly because of my skills but also because of the prevailing light wind conditions, I wasted money in buying one shortboard after the other, in the hope to find the " best" one, to eventually find out that planing and shortboarding here ( mostly with 10-12 knts winds) is like trying to sell a refrigerator to an Inuit in the North Pole..
Eventually I bought an 11 ft Bic Behemoth ( sort of wind-adapted paddleboard) with which at least I windsurf when others can't..., albeit at the price of a slow pace and..some boredom when winds are really slow.

With foiling, I hope to break this barrier ( if I don't break something else when falling from a height of 85 cm..), but I take risks and at my age I have nothing to lose, even $ 400 is not a big deal, should I find out that foiling is not for me ...
"

He's got a bit of a history of asking for advice, then ignoring it, and ending up disappointed. Taking bets now on him deciding that foiling "is not for him" because he can't get going on a small front wing with a non-foil board in 10-12 knots.

segler
WA, 1623 posts
12 Feb 2020 1:00AM
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So, for OP, this is not undoable in 10-12 mph winds. (How's that for a double negative with an invented word?) Now that we know more from his US posting, we can focus in on recommendations.

Get the foil for $400 CAD. No problem. Use a deep tuttle big slalom or formula board, volume 145-160 liter, width 80-100 cm. Leave off the footstraps; ride strapless. Use a 7.0 or 8.0 sail (maybe 8.5). Rig it up and hit the water. You will crash. Even from 85 cm up, crashes are not all that bad. Be sure to keep a grip on to the boom when you crash. Never let go.

You will build up your TOF (time on foil) and muscle memory. If your gear is balanced, it will begin to click nicely after about 12 hours. I know this from experience.

You will foil in 10-12 mph winds. Get used to pumping up to a slow plane, then up onto the wing. Keep it low and flat. Enjoy life.

Once you are hooked, you will be saving up for newer gear. No problem. We all did this.

Paducah
2546 posts
12 Feb 2020 1:56AM
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Select to expand quote
segler said..
So, for OP, this is not undoable in 10-12 mph winds. (How's that for a double negative with an invented word?) Now that we know more from his US posting, we can focus in on recommendations.

Get the foil for $400 CAD. No problem. Use a deep tuttle big slalom or formula board, volume 145-160 liter, width 80-100 cm. Leave off the footstraps; ride strapless. Use a 7.0 or 8.0 sail (maybe 8.5). Rig it up and hit the water. You will crash. Even from 85 cm up, crashes are not all that bad. Be sure to keep a grip on to the boom when you crash. Never let go.

You will build up your TOF (time on foil) and muscle memory. If your gear is balanced, it will begin to click nicely after about 12 hours. I know this from experience.

You will foil in 10-12 mph winds. Get used to pumping up to a slow plane, then up onto the wing. Keep it low and flat. Enjoy life.

Once you are hooked, you will be saving up for newer gear. No problem. We all did this.


Segler, I respectfully disagree. I'm willing to bet at least a beer that the RS:One wing is around 750cm2. That was pretty much the standard in '17 when it came out.

Generally, you make good points. However, OP lives in a world of 10-12 wind with a limited sail selection. This is the important information. Even getting to the speed for that wing to take off will be problematic. Unless his light wind skills are really. really sharp - he's going to bob around on those days or spend months at that awful "almost going fast enough, come out of the water, plop back down and then get pulled over the handlebars" stage.

IMHO, he's better off waiting for a used foil that better suits him to shake loose than chasing this "deal". I'm not saying it's a bad foil. Give it to a smaller person 60-70 kg or someone who lives somewhere windier; and let them have a blast on it. Spending $400 on something that's not going where you want to go is a ticket to frustration. It's like all those cheap CraigsList boards we can't talk people out of. "Oh, I'm going to try it and if I like it I'll get proper gear." ... and we never see them again.

gorgesailor
604 posts
12 Feb 2020 2:12AM
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Select to expand quote
Paducah said..

segler said..
So, for OP, this is not undoable in 10-12 mph winds. (How's that for a double negative with an invented word?) Now that we know more from his US posting, we can focus in on recommendations.

Get the foil for $400 CAD. No problem. Use a deep tuttle big slalom or formula board, volume 145-160 liter, width 80-100 cm. Leave off the footstraps; ride strapless. Use a 7.0 or 8.0 sail (maybe 8.5). Rig it up and hit the water. You will crash. Even from 85 cm up, crashes are not all that bad. Be sure to keep a grip on to the boom when you crash. Never let go.

You will build up your TOF (time on foil) and muscle memory. If your gear is balanced, it will begin to click nicely after about 12 hours. I know this from experience.

You will foil in 10-12 mph winds. Get used to pumping up to a slow plane, then up onto the wing. Keep it low and flat. Enjoy life.

Once you are hooked, you will be saving up for newer gear. No problem. We all did this.



Segler, I respectfully disagree. I'm willing to bet at least a beer that the RS:One wing is around 750cm2. That was pretty much the standard in '17 when it came out.

Generally, you make good points. However, OP lives in a world of 10-12 wind with a limited sail selection. This is the important information. Even getting to the speed for that wing to take off will be problematic. Unless his light wind skills are really. really sharp - he's going to bob around on those days or spend months at that awful "almost going fast enough, come out of the water, plop back down and then get pulled over the handlebars" stage.

IMHO, he's better off waiting for a used foil that better suits him to shake loose than chasing this "deal". I'm not saying it's a bad foil. Give it to a smaller person 60-70 kg or someone who lives somewhere windier; and let them have a blast on it. Spending $400 on something that's not going where you want to go is a ticket to frustration. It's like all those cheap CraigsList boards we can't talk people out of. "Oh, I'm going to try it and if I like it I'll get proper gear." ... and we never see them again.


I agree, I don't think he's up for the challenge of that wing. IMHO to have any chance of success he needs the easiest wing possible...

boardsurfr
WA, 2335 posts
12 Feb 2020 5:45AM
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The one question is how the "10-12 mph" are measured - with a hand-held meter on shore, or with an iWindsurf or airport windmeter. It's a big difference. A couple of days ago, I measured averages near 10 mph and gusts of 13 mph on shore (side onshore wind, clear fetch, standing about 2 meters above water level). An iWindsurf meter that's about 3 km away read averages of 20 with gusts to 25. I went out on a 7.8 and was planing fine once I got out a bit. Yesterday morning in stronger winds, the differences were lower (perhaps 3-4 mph lower on the hand-held meter). The biggest difference is that iWindsurf (and airport) meters are usually 10 meters above ground. Wind speeds 10 meter above ground are about 20-40% higher than at 2 meters (numbers from wind-data.ch/tools/profile.php). "Roughness" of the water and the beach determine the exact amount.

I need about 13 mph gusting to 15 to foil on a i84 with a 6.5 m sail. I'm an intermediate foiler (good height control and tacks, bad jibes) and pumper. That's using 10-m wind data; handheld meters would probably show about 10 mph gusting to 12. I'm somewhere around 85 kg. Even after about 50 foil sessions so far, I would not have a chance to foil on a 800 cm2 wing in these conditions.

martyj4
515 posts
12 Feb 2020 10:51AM
Thumbs Up

Hey Francone.
What are you looking to do with foiling? For me (and I MAY be wrong here) and it sounds like for you, you're aiming to get out and get sailing in lowish windspeeds (10-15 knots)?? We have lots of iffy seabreezes here that often struggle to get near 15 knots, so foiling was the obvious choice to extend our time on water. If you want to go real fast, then my advice may not be so relevant.
I went for the 1220cm2 Naish foil initially. Coupled it with my 5.3m wavesail and was getting going in 13ish knots. It was a good foil to learn on but by no means the best.
I've since bought one of the 1570cm2 Naish front wings and can now get going in around 11 knots with a 5.3/5.7 sail. For me, the bigger foil wing area means the wind threshold to get you up and flying is reduced (13 down to around 11 knots now). That's what I'm after. Compromise is top speed - the 1570 feels like it's hitting 3rd gear and just won't go any faster. But that's fine with me. If you're after top end speed, then the bigger area foils seem to have a lot of drag, so that may not be what you want.
You can get smaller wings and put bigger sails on to try and compensate, but I think it gets harder to get it flying by doing that. Big foils and smaller sails seem to work better for me. And in lighter winds I find pumping a smaller sail is much easier to get the foil flying.
It may also be me, but I've found that a front footstrap at least is good for securing your foot when you're trying to pump the foil up. Could ditch the back one without any dramas.
And with the front wings, I've also found that the wider width of the foil has a tendency to make it react slower to foot steering. So for learning, that's another beneficial thing.
Good luck. It's a load of fun.

Oh and I have 'grounded' the old naish front wing on rocks before. The carbon has a couple of small scratches - that was it. The box took it really well too. No noticable damage.

segler
WA, 1623 posts
13 Feb 2020 12:42AM
Thumbs Up

I can't disagree. If, indeed, the RS One wing area is way down there in the 700s, then, yes, it is far too small to learn on. For some reason I got the impression it is bigger.

So, stick with the range of 1100-1500 cm2. Just bite the bullet and get the Slingshot aluminum with the i76. If you find you need to use a Power Plate, it is easy with the Slingshot.

Paducah
2546 posts
17 Feb 2020 2:25PM
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Rob Hofmann (who I dare say is probably pushing a bit more than 85 kg) on a Starboard SuperCruiser and 6.7 sail jibing in 10 knots

www.facebook.com/rob.hofmann.5/videos/2823703594335154/

Sideshore
282 posts
18 Apr 2020 11:41PM
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Select to expand quote
martyj4 said..
Hey Francone.
What are you looking to do with foiling? For me (and I MAY be wrong here) and it sounds like for you, you're aiming to get out and get sailing in lowish windspeeds (10-15 knots)?? We have lots of iffy seabreezes here that often struggle to get near 15 knots, so foiling was the obvious choice to extend our time on water. If you want to go real fast, then my advice may not be so relevant.
I went for the 1220cm2 Naish foil initially. Coupled it with my 5.3m wavesail and was getting going in 13ish knots. It was a good foil to learn on but by no means the best.
I've since bought one of the 1570cm2 Naish front wings and can now get going in around 11 knots with a 5.3/5.7 sail. For me, the bigger foil wing area means the wind threshold to get you up and flying is reduced (13 down to around 11 knots now). That's what I'm after. Compromise is top speed - the 1570 feels like it's hitting 3rd gear and just won't go any faster. But that's fine with me. If you're after top end speed, then the bigger area foils seem to have a lot of drag, so that may not be what you want.
You can get smaller wings and put bigger sails on to try and compensate, but I think it gets harder to get it flying by doing that. Big foils and smaller sails seem to work better for me. And in lighter winds I find pumping a smaller sail is much easier to get the foil flying.
It may also be me, but I've found that a front footstrap at least is good for securing your foot when you're trying to pump the foil up. Could ditch the back one without any dramas.
And with the front wings, I've also found that the wider width of the foil has a tendency to make it react slower to foot steering. So for learning, that's another beneficial thing.
Good luck. It's a load of fun.

Oh and I have 'grounded' the old naish front wing on rocks before. The carbon has a couple of small scratches - that was it. The box took it really well too. No noticable damage.


Hello martyj4
Thank you for your interesting information, I totally agree with your philosophy. The only data I miss is your weight. Could you give it ?

I've ordered the neil pryde glidewind small because the experiences on internet about the M size say it doesn't work well in windfoiling. I weight only 69 Kg, 125 freeride powerbox board and I hope to fly with a 5,5 m2 sail in 12 knots.

KR

thedoor
2302 posts
19 Apr 2020 12:20AM
Thumbs Up

I know some people are also installing tracks into old boards to convert them for wingfoiling. Can't see why you couldn't do it for windfoiling

LeeD
3939 posts
19 Apr 2020 1:56AM
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Lecum.
Glide med works great for a 71 kg bud who currently rides the 5'10" RRD Pocket.
At 15 knot breeze, he uses 4.5.
Still owns a Flight, but hasn't used it for 14 months.
He foiljibes at around 90% rate.

Sideshore
282 posts
25 Apr 2020 11:26PM
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Select to expand quote
LeeD said..
Lecum.
Glide med works great for a 71 kg bud who currently rides the 5'10" RRD Pocket.
At 15 knot breeze, he uses 4.5.
Still owns a Flight, but hasn't used it for 14 months.
He foiljibes at around 90% rate.


And can your friend fly with ligther wind and 5,3 sail with the same foil?

LeeD
3939 posts
26 Apr 2020 12:00AM
Thumbs Up

Of course.
I had to state a windspeed for an example.
Yesterday he was out on 5.6 Gaastra Hybrid in around 5-13 knot breezes, and foiling at the higher end. Around 152 lbs, but 4/3 wetsuit added.
He's on the little 5'10" board, so won't be using 7 meter sails.



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Forums > Windsurfing Foiling


"Foiling, stress on the finbox and sail size" started by Francone