Playlist:

www.youtube.com/playlist?list=PLP7KGVZy0gFSyhgcUVkqS4_nSAlkFnaiW

The sailor's C.G.? The foil angle of attack? I wonder how they instrumented that? However they did, it's the coolest thing I've seen in a windfoil tutorial!

Very good video's. I pretty much never agree with anyone when it comes to foiling technique, but Sam Ross and I are pretty much 100% on the same line except for some really minor details.

I think its in part because he (like me) uses faster equipment than most others who have instructional videos. He clearly prefers the GTR or Race for his own sailing.

With the board in front of him and two foils in hand, he missed an opportunity to show us that the center of lift of the front wing has to be at the midpoint between front and rear footstraps.

Talking about making adjustments as a RESULT is fine, but why not talk about CAUSE?

It is the position of the front wing between the footstraps that can cause the back leg to burn (wing too far aft) or the out of control condition (wing too far forward). Start there, THEN adjust mast base and footstraps to fine-tune.

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segler said..
With the board in front of him and two foils in hand, he missed an opportunity to show us that the center of lift of the front wing has to be at the midpoint between front and rear footstraps.

Talking about making adjustments as a RESULT is fine, but why not talk about CAUSE?

It is the position of the front wing between the footstraps that can cause the back leg to burn (wing too far aft) or the out of control condition (wing too far forward). Start there, THEN adjust mast base and footstraps to fine-tune.

Yeah but thats plain not true. The wing doesnt have to be at the midpoint, its even better if it is further forward, also for freeride foiling. He explained perfectly that there are different foils and different wants and needs depending on your level. With either foil he showed its not possible to get the center of lift of the frontwing at the midpoint between the feet, and that is with the board that was designed with it.

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WhiteofHeart said..
...I think its in part because he (like me) uses faster equipment than most others who have instructional videos. He clearly prefers the GTR or Race for his own sailing.

Yeah, he's just yacking along into his microphone and I'm watching the knots click up into the mid 20s.

There is a reason why both Sailworks and Slingshot (and all instructors) say to start with the center of lift of the front wing at, or near, the midpoint between front and back foot. It is called balance.

If the wing is too far forward, you can't control it. It will fly up and breach.

If the wing is too far aft, you can't lift it. Might as well just keep slapping.

Moving the sail mast base fore and aft is great for fine-tuning, but does not work at all for coarse-tuning.

I know this from experience. For both myself and others, I have set up a dozen different boards and a dozen different foils, even different TYPES of foils. If you don't start with the front wing at or near the midpoint, you are just gonna get frustrated.

Fortunately, if you purchase a matched set, such as Slingshot boards and foils together, they come already balanced.

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segler said..
There is a reason why both Sailworks and Slingshot (and all instructors) say to start with the center of lift of the front wing at, or near, the midpoint between front and back foot. It is called balance.

If the wing is too far forward, you can't control it. It will fly up and breach.

If the wing is too far aft, you can't lift it. Might as well just keep slapping.

Moving the sail mast base fore and aft is great for fine-tuning, but does not work at all for coarse-tuning.

I know this from experience. For both myself and others, I have set up a dozen different boards and a dozen different foils, even different TYPES of foils. If you don't start with the front wing at or near the midpoint, you are just gonna get frustrated.

Fortunately, if you purchase a matched set, such as Slingshot boards and foils together, they come already balanced.

Yeah, but you can still balance things with wing forward by weighting the front foot more. I think this is preferential as you have lots of potential to increase back foot pressure for popping onto the foil or to maintain flight during lulls.

I find his statement interesting for boom height in the following video as he suggest keeping the boom high will allow more stable run since this forces keeping the legs in locked position. I will try this next time. Other sites were recommending lower boom height.

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SA_AL said..
I find his statement interesting for boom height in the following video as he suggest keeping the boom high will allow more stable run since this forces keeping the legs in locked position. I will try this next time. Other sites were recommending lower boom height.

Raising the boom increases lateral stability and increases power (and therefore decreases longitudinal stability/control) is my experience. I suppose thats why some say a higher boom increases control and others say a lower boom does.

Thedoor is certainly right-on about weighting the front foot more. Students and beginners (and experienced dudes like me) just generally prefer equal weight on both feet. Easier and more relaxing. (At my age, I need more relaxing. I don't need or like leg burn.)

Nice thing about the shovel-shaped wings is that their center of lift is fairly long, thus allowing for easy adjustment of balance. I retired an old 2016 hand-built foil and replaced it with a SS i76, mounted in the same place. It flies fine, but I have to foil front-foot-heavy most of the time, and it too-easily breaches during gusts. I can compensate by keeping the back foot forward of its footstrap and/or by moving the sail mast base further forward. Today I will mount the foil 2 inches further aft.

That worked. Two inches further aft helped keep things better under control in gusts. Ease of takeoff and foot weighting is unchanged.

There is a reason why the i76 is so popular worldwide.

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segler said..
That worked. Two inches further aft helped keep things better under control in gusts. Ease of takeoff and foot weighting is unchanged.

There is a reason why the i76 is so popular worldwide.

I have progressively moved the 76 back on my Levitator. I'm now at 2cm from the most aft position and my weight is much better balanced until I get overpowered. Then, it's foot out of the back strap and more forward sailing upwind (I don't sail in the back strap reaching). I guess my take on that is either I need a smaller sail or a smaller wing. I suppose I can move the UJ further forward too but I'm already in the middle of a rather long track.

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segler said..
Thedoor is certainly right-on about weighting the front foot more. Students and beginners (and experienced dudes like me) just generally prefer equal weight on both feet. Easier and more relaxing. (At my age, I need more relaxing. I don't need or like leg burn.)

Nice thing about the shovel-shaped wings is that their center of lift is fairly long, thus allowing for easy adjustment of balance. I retired an old 2016 hand-built foil and replaced it with a SS i76, mounted in the same place. It flies fine, but I have to foil front-foot-heavy most of the time, and it too-easily breaches during gusts. I can compensate by keeping the back foot forward of its footstrap and/or by moving the sail mast base further forward. Today I will mount the foil 2 inches further aft.

I seem to have my infinity 76 balanced pretty good, but I blew up big-time after breaching at speed on my infinity 65 yesterday, so I guess I need to move the foil mast further back for the 65. I was riding it one inch in forward of the 76 (all other settings the same).

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thedoor said..

segler said..
Thedoor is certainly right-on about weighting the front foot more. Students and beginners (and experienced dudes like me) just generally prefer equal weight on both feet. Easier and more relaxing. (At my age, I need more relaxing. I don't need or like leg burn.)

Nice thing about the shovel-shaped wings is that their center of lift is fairly long, thus allowing for easy adjustment of balance. I retired an old 2016 hand-built foil and replaced it with a SS i76, mounted in the same place. It flies fine, but I have to foil front-foot-heavy most of the time, and it too-easily breaches during gusts. I can compensate by keeping the back foot forward of its footstrap and/or by moving the sail mast base further forward. Today I will mount the foil 2 inches further aft.

I seem to have my infinity 76 balanced pretty good, but I blew up big-time after breaching at speed on my infinity 65 yesterday, so I guess I need to move the foil mast further back for the 65. I was riding it one inch in forward of the 76 (all other settings the same).

It depends a little on how / where the front wing is connected to the fuselage, but generally higher aspect wings also have the center of lift further forward. This is due the wings mostly mounting with the leading edge lineing up to some groove / point on the fuselage and the lower aspect wings therefore extending further back.

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WhiteofHeart said..

thedoor said..

segler said..
Thedoor is certainly right-on about weighting the front foot more. Students and beginners (and experienced dudes like me) just generally prefer equal weight on both feet. Easier and more relaxing. (At my age, I need more relaxing. I don't need or like leg burn.)

Nice thing about the shovel-shaped wings is that their center of lift is fairly long, thus allowing for easy adjustment of balance. I retired an old 2016 hand-built foil and replaced it with a SS i76, mounted in the same place. It flies fine, but I have to foil front-foot-heavy most of the time, and it too-easily breaches during gusts. I can compensate by keeping the back foot forward of its footstrap and/or by moving the sail mast base further forward. Today I will mount the foil 2 inches further aft.

I seem to have my infinity 76 balanced pretty good, but I blew up big-time after breaching at speed on my infinity 65 yesterday, so I guess I need to move the foil mast further back for the 65. I was riding it one inch in forward of the 76 (all other settings the same).

It depends a little on how / where the front wing is connected to the fuselage, but generally higher aspect wings also have the center of lift further forward. This is due the wings mostly mounting with the leading edge lineing up to some groove / point on the fuselage and the lower aspect wings therefore extending further back.

When I compare them visually it doesn't look like that which is why I probably went with the one in forward setting, but its kind of a subjective evaluation. The higher speed moves the lift forward too or not?

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thedoor said..

WhiteofHeart said..

thedoor said..

segler said..
Thedoor is certainly right-on about weighting the front foot more. Students and beginners (and experienced dudes like me) just generally prefer equal weight on both feet. Easier and more relaxing. (At my age, I need more relaxing. I don't need or like leg burn.)

Nice thing about the shovel-shaped wings is that their center of lift is fairly long, thus allowing for easy adjustment of balance. I retired an old 2016 hand-built foil and replaced it with a SS i76, mounted in the same place. It flies fine, but I have to foil front-foot-heavy most of the time, and it too-easily breaches during gusts. I can compensate by keeping the back foot forward of its footstrap and/or by moving the sail mast base further forward. Today I will mount the foil 2 inches further aft.

I seem to have my infinity 76 balanced pretty good, but I blew up big-time after breaching at speed on my infinity 65 yesterday, so I guess I need to move the foil mast further back for the 65. I was riding it one inch in forward of the 76 (all other settings the same).

It depends a little on how / where the front wing is connected to the fuselage, but generally higher aspect wings also have the center of lift further forward. This is due the wings mostly mounting with the leading edge lineing up to some groove / point on the fuselage and the lower aspect wings therefore extending further back.

When I compare them visually it doesn't look like that which is why I probably went with the one in forward setting, but its kind of a subjective evaluation. The higher speed moves the lift forward too or not?

My mistake, those look pretty equal! Hadn't thought about this specific slide-over connection (tbh I couldnt remember what the slingshot connection looks like). To be honest it looks they made an effort to put the power in the same place when designing the thing, for structurally this isnt the option I would go for, although balance wise it makes much more sense! I would probably have extend the trailing edge further back to have the center of lift closer to the connection with the fuselage in order to minimise the lever between the wing and fuselage, if that makes sense?
Yes you are right, as speed increases power shifts forward.

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WhiteofHeart said..

thedoor said..

WhiteofHeart said..

thedoor said..

segler said..
Thedoor is certainly right-on about weighting the front foot more. Students and beginners (and experienced dudes like me) just generally prefer equal weight on both feet. Easier and more relaxing. (At my age, I need more relaxing. I don't need or like leg burn.)

Nice thing about the shovel-shaped wings is that their center of lift is fairly long, thus allowing for easy adjustment of balance. I retired an old 2016 hand-built foil and replaced it with a SS i76, mounted in the same place. It flies fine, but I have to foil front-foot-heavy most of the time, and it too-easily breaches during gusts. I can compensate by keeping the back foot forward of its footstrap and/or by moving the sail mast base further forward. Today I will mount the foil 2 inches further aft.

I seem to have my infinity 76 balanced pretty good, but I blew up big-time after breaching at speed on my infinity 65 yesterday, so I guess I need to move the foil mast further back for the 65. I was riding it one inch in forward of the 76 (all other settings the same).

It depends a little on how / where the front wing is connected to the fuselage, but generally higher aspect wings also have the center of lift further forward. This is due the wings mostly mounting with the leading edge lineing up to some groove / point on the fuselage and the lower aspect wings therefore extending further back.

When I compare them visually it doesn't look like that which is why I probably went with the one in forward setting, but its kind of a subjective evaluation. The higher speed moves the lift forward too or not?

My mistake, those look pretty equal! Hadn't thought about this specific slide-over connection (tbh I couldnt remember what the slingshot connection looks like). To be honest it looks they made an effort to put the power in the same place when designing the thing, for structurally this isnt the option I would go for, although balance wise it makes much more sense! I would probably have extend the trailing edge further back to have the center of lift closer to the connection with the fuselage in order to minimise the lever between the wing and fuselage, if that makes sense?
Yes you are right, as speed increases power shifts forward.

Perhaps they want a certain depth of insertion of the fuselage into the wing. Either way next session o the small one I will scoot the foil mast back an inch and try that

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thedoor said..

WhiteofHeart said..

thedoor said..

WhiteofHeart said..

thedoor said..

segler said..
Thedoor is certainly right-on about weighting the front foot more. Students and beginners (and experienced dudes like me) just generally prefer equal weight on both feet. Easier and more relaxing. (At my age, I need more relaxing. I don't need or like leg burn.)

Nice thing about the shovel-shaped wings is that their center of lift is fairly long, thus allowing for easy adjustment of balance. I retired an old 2016 hand-built foil and replaced it with a SS i76, mounted in the same place. It flies fine, but I have to foil front-foot-heavy most of the time, and it too-easily breaches during gusts. I can compensate by keeping the back foot forward of its footstrap and/or by moving the sail mast base further forward. Today I will mount the foil 2 inches further aft.

I seem to have my infinity 76 balanced pretty good, but I blew up big-time after breaching at speed on my infinity 65 yesterday, so I guess I need to move the foil mast further back for the 65. I was riding it one inch in forward of the 76 (all other settings the same).

It depends a little on how / where the front wing is connected to the fuselage, but generally higher aspect wings also have the center of lift further forward. This is due the wings mostly mounting with the leading edge lineing up to some groove / point on the fuselage and the lower aspect wings therefore extending further back.

When I compare them visually it doesn't look like that which is why I probably went with the one in forward setting, but its kind of a subjective evaluation. The higher speed moves the lift forward too or not?

My mistake, those look pretty equal! Hadn't thought about this specific slide-over connection (tbh I couldnt remember what the slingshot connection looks like). To be honest it looks they made an effort to put the power in the same place when designing the thing, for structurally this isnt the option I would go for, although balance wise it makes much more sense! I would probably have extend the trailing edge further back to have the center of lift closer to the connection with the fuselage in order to minimise the lever between the wing and fuselage, if that makes sense?
Yes you are right, as speed increases power shifts forward.

Perhaps they want a certain depth of insertion of the fuselage into the wing. Either way next session o the small one I will scoot the foil mast back an inch and try that

If it's windy or in big swells I'd move the 65 back to the Tuttle equivalent position.
Even though the 65 is only around half the surface area of the 76 it seems to generate as much lift - I guess because it's quicker

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azymuth said..

thedoor said..

WhiteofHeart said..

thedoor said..

WhiteofHeart said..

thedoor said..

segler said..
Thedoor is certainly right-on about weighting the front foot more. Students and beginners (and experienced dudes like me) just generally prefer equal weight on both feet. Easier and more relaxing. (At my age, I need more relaxing. I don't need or like leg burn.)

Nice thing about the shovel-shaped wings is that their center of lift is fairly long, thus allowing for easy adjustment of balance. I retired an old 2016 hand-built foil and replaced it with a SS i76, mounted in the same place. It flies fine, but I have to foil front-foot-heavy most of the time, and it too-easily breaches during gusts. I can compensate by keeping the back foot forward of its footstrap and/or by moving the sail mast base further forward. Today I will mount the foil 2 inches further aft.

I seem to have my infinity 76 balanced pretty good, but I blew up big-time after breaching at speed on my infinity 65 yesterday, so I guess I need to move the foil mast further back for the 65. I was riding it one inch in forward of the 76 (all other settings the same).

It depends a little on how / where the front wing is connected to the fuselage, but generally higher aspect wings also have the center of lift further forward. This is due the wings mostly mounting with the leading edge lineing up to some groove / point on the fuselage and the lower aspect wings therefore extending further back.

When I compare them visually it doesn't look like that which is why I probably went with the one in forward setting, but its kind of a subjective evaluation. The higher speed moves the lift forward too or not?

My mistake, those look pretty equal! Hadn't thought about this specific slide-over connection (tbh I couldnt remember what the slingshot connection looks like). To be honest it looks they made an effort to put the power in the same place when designing the thing, for structurally this isnt the option I would go for, although balance wise it makes much more sense! I would probably have extend the trailing edge further back to have the center of lift closer to the connection with the fuselage in order to minimise the lever between the wing and fuselage, if that makes sense?
Yes you are right, as speed increases power shifts forward.

Perhaps they want a certain depth of insertion of the fuselage into the wing. Either way next session o the small one I will scoot the foil mast back an inch and try that

If it's windy or in big swells I'd move the 65 back to the Tuttle equivalent position.
Even though the 65 is only around half the surface area of the 76 it seems to generate as much lift - I guess because it's quicker

Azy do you run the 65 and the 76 in the same foil mast position most of the time? If so do you keep the sail mast the same for the 65 and 76.

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thedoor said.. Azy do you run the 65 and the 76 in the same foil mast position most of the time? If so do you keep the sail mast the same for the 65 and 76.

Foil mast;
W105 and F87, Infinity 76 & 65 - fuselage position B, Tuttle box.


Sail mast (mast base);
W105;
Wind 10-15 knots - 76, rear mast track,
15-20 knots - 76, mid mast track; 65, rear mast track.

F87;
15-20 knots - 76 & 65, 5-10 cm from front of mast track.
20+ knots - 65, right at front of mast track.

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azymuth said..

thedoor said.. Azy do you run the 65 and the 76 in the same foil mast position most of the time? If so do you keep the sail mast the same for the 65 and 76.

Foil mast;
W105 and F87, Infinity 76 & 65 - fuselage position B, Tuttle box.


Sail mast (mast base);
W105;
Wind 10-15 knots - 76, rear mast track,
15-20 knots - 76, mid mast track; 65, rear mast track.

F87;
15-20 knots - 76 & 65, 5-10 cm from front of mast track.
20+ knots - 65, right at front of mast track.

Cheers

One more question: for the same wind speed how much extra sail do you need to switch from the 76 to 65?

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thedoor said.. One more question: for the same wind speed how much extra sail do you need to switch from the 76 to 65?

Not sure I need extra sail to switch to the 65.
But I'll often change from the 76 to the 65 if the wind increases - it's quicker than changing sails.
Easier to foil overpowered with the smaller wing.

15 knots - 5m Simmer Tricera - 76 & 65.
Wind increases to 20 knots. Keep 76 and change to 4.5m or change to 65 and keep the 5m.

The 65 is pretty amazing in lighter winds too.
Jonah and I were still having fun on Freestyle 87s, 65s, and 4.5m sails today when the wind had dropped from 18 knots to a gusty 12 to 15 knots.
It's bizarre how one moment you're dredging submerged going nowhere then a gust of a couple more knots comes along and in seconds you're flying at 20 knots.

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azymuth said..

thedoor said.. One more question: for the same wind speed how much extra sail do you need to switch from the 76 to 65?

Not sure I need extra sail to switch to the 65.
But I'll often change from the 76 to the 65 if the wind increases - it's quicker than changing sails.
Easier to foil overpowered with the smaller wing.

15 knots - 5m Simmer Tricera - 76 & 65.
Wind increases to 20 knots. Keep 76 and change to 4.5m or change to 65 and keep the 5m.

The 65 is pretty amazing in lighter winds too.
Jonah and I were still having fun on Freestyle 87s, 65s, and 4.5m sails today when the wind had dropped from 18 knots to a gusty 12 to 15 knots.
It's bizarre how one moment you're dredging submerged going nowhere then a gust of a couple more knots comes along and in seconds you're flying at 20 knots.

I am still dialing the 65. My best sessions on it, so far, have been when it's flat and the wind is steady. If there are swells to ride I like the slower 76 and if its gusty I like the 76. I need to give the 65 more water time and hopefully those Bay Area summer seabreeze's will give me the option soon. We don't call ours the doctor but its equally as good.