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Hypernut 2018/2019/2020 foil box position/angle

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Created by themorb > 9 months ago, 7 Jul 2020
themorb
4 posts
7 Jul 2020 11:58PM
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I recently bought a 2018 7'4" Hypernut 4-in-1 and the previous owner mentioned putting a shim in the tuttle box to get the nose of the board down and parallel with the foil fuselage. I got a SuperCruiser foil and tried it without a shim and it seemed to require more wind than I expected with 5.5m sail to get up. (However I am a foil beginner, so I'm sure lack of skill isn't helping.)

Then I tried creating a shim and found a longer screw and discovered the tuttle head needs to be proud of the board by about 15 mm at the rear to get the fuselage parallel. Obviously this is a bit subjective because the board has rocker but I was trying to get it parallel to the overall flattest part of the board. If my calculations are correct, a 15 mm shim equates to the nose of the board dropping about 9" / 23 cm which seems quite significant. I went out in less wind than before and it seemed to pop up on foil much easier. I was doing ~1 km reaches flying most of the time with some gentle touchdowns on swell and no major crashes.

Now I see that on the 2020 Starboard website they list the distance from the tail of the board to the middle of the foil box as being 47.5 cm for the 7'4" 4-in-1 version. They did not list this figure for 2019 or 2018. I measured mine and found it to be 33.5 cm. The previous owner of my 2018 replaced it with a 2019 and he said he didn't notice a difference in foil box position. I don't know whether he still uses a shim or not.

My questions are:
1. Does anybody know if the angle of the box also changed in 2020?
2. Is there any issue with using a 15 mm shim in my box? It seems it would reduce strength as now the tuttle head angles are all wrong and not making full contact with the box. Perhaps there is some sort of moulding putty/clay I could use to form a proper shim that makes contact on all sides?
3. Would I be completely crazy to cut in a new box (perhaps the Blue Planet Strong Box) directly in front of the existing box? I could set the angle to my preference. (So far I can't find a genuine Starboard deck pad available but maybe I can find generic red and blue pads and piece them together to make it look acceptable)
4. Am I over-thinking this as a beginner foiler? Should I just get more time on the water and maybe I will get used to it?

Thanks!!!!! Foiling is so much fun!!! And opens up so many new light wind opportunities windsurfing!!!!

Smidgeuk
70 posts
8 Jul 2020 4:47PM
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I have the 8ft, 2019 hypernut 4in1. I havent noticed a problem. Its entirely normal for beginners to find that the magic of foiling in next to no wind is much harder than they thought (it may be that the success on your second go was just learning). It takes technique to pump the sail and pump the board and get settled nicely once up (and I havent mastered it...). Its best to begin with a bit more wind, or only get up in the occasional gust. Also, the hypernut is basically a wave SUP, it has rounded rails and tail rocker. It therefore does not develop the initial board speed in light winds as well as a specialist foil board or even a battered old slalom or formula board. Its therefore more reliant on sail and foil pumping technique to take off in the light stuff.

I would be nervous about shimming the tuttle box - there is a lot of force going through there. If you need to shim anything then shim the rear wing with a washer (assuming you can on the super cruiser) - as that is an established technique and the forces shouldnt be so worrisome. But you can probably achieve what you want by playing around with the mast base position. Try putting it towards back of the track. And try taking off the back footstrap and putting your foot a bit further back.

I wouldnt put a second box in - just do more practice. And if its really not working then move on to something else (either foil or board). SLingshot system has benefit of being able to use the twin track and change the fuselage position such that you can move the front wing a long way forward if needed.

AlexF
484 posts
8 Jul 2020 9:01PM
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AFAIK the box in the 8'0 is and was positioned further forward than in the 7'4 ?
Long times ago i posted my thoughts on why there are some things not perfect on the Hypernuts (and other serial 4in1 boards) for windfoiling in this forum (or the sailboardforum, i don't know anymore??), and why i ordered a custom board because of that, but i'm lazy to search for the forum threads.
One thing was the nonexistent compensation of the rocker in the foilboxes (my custom has it).
Next thing you will notice is the position of the rear footstraps too far outside.
And then that the position of the foilboxes fits either the trimm with a classic windfoil with a longer fuselage (distance mast to frontwing) or with a supfoil with shorter fuselage.
Then the weight (my custom weighs 9,1 kg, fully foilbox-equipped, 130 liters)

And i also think using a 15mm shim on your board could lead to some stability problems with your box.

Alex

segler
WA, 1597 posts
9 Jul 2020 12:03AM
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Do not shim a tuttle box. It will create point loads which will destroy the box. You always want full and intimate contact of the foil top fitting to the fore and aft tapers inside the box. You do NOT want contact to the inside top of the box. Left and right side contact is obvious.

themorb
4 posts
9 Jul 2020 1:56AM
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Select to expand quote
segler said..
Do not shim a tuttle box. It will create point loads which will destroy the box. You always want full and intimate contact of the foil top fitting to the fore and aft tapers inside the box. You do NOT want contact to the inside top of the box. Left and right side contact is obvious.


I was thinking more about this... you are right, although with light enough wind and rider (I am 68 kgs) and no jumps or crazy antics, it would survive a while before breakage.

Shimming the top of the box creates triangular voids on the fore and aft tapers. I was thinking I could calculate these and fabricate plastic wedges to distribute the load.

Alternatively -- the aluminum Starboard foil mast has a plastic head encasing the aluminum mast. Theoretically a person could fabricate a new plastic head which leaves the aluminum mast at a different angle. This would be the ultimate solution. I wonder if I could use some sort of casting resin with a release agent... need to be careful otherwise the mast may end up permanently glued in the box

themorb
4 posts
9 Jul 2020 12:28PM
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Stopped at a fibreglass/hobby shop on my way home from work... found some casting plastic and release agent....... made a quick wooden support...... Covered all holes with tuck tape..... We shall see if it all comes apart tomorrow or if I have permanently glued my foil to my board

Yes, I made an error by not having the top of the box level so I wasn't able to fill it to the top at the front. We will call this prototype v0.1 for proof of concept I could always pour another one. If they work, I could pour a few at different angles and swap them at the beach.


















dantren
QLD, 289 posts
9 Jul 2020 5:46PM
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I'll share my experience with a 2018 Hypernut 4in1 133L.
It was a great board to sup & windsup, but difficult to windfoil - especially for a beginner.
I found the board really held back my windfoil progression, mainly due to the front foot strap position. It's just way too far forward.......
You can tell just by looking at it, compared to other foil boards.
Don't get me wrong, I loved the board but moving to a dedicated windfoil board(Naish 122 Hover) gave me heaps better performance & confidence.
Not sure the foil box is the root of your issue mate.

themorb
4 posts
9 Jul 2020 11:39PM
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I had good success without foot straps. Using 4.5-5.5 wave sails and slow foil - maybe bigger sails and faster speed are more inclined towards straps?

De-moulded my casting and it appears to have worked!!! Some small bubbles apparently can be caused by too much release agent or ambient moisture but I think this is a good start! I'll probably make another one tonight at half the angle and then next time I am at the beach I will have 3 settings to try.

My theory for changing the angle is that for the foil to lift the fuselage should pretty close to level. With it angled down so much you have to push the tail of the board down significantly to get it to lift - ploughing the board through the water less efficiently. Once you are flying it's not a big deal to have the nose of the board pointing up a bit, but it is the light-wind take-off I am concerned about. I agree the Hypernut with its rocker will never be as efficient as a dedicated flat bottomed foil board but this is what I've got for now and I really like it for SUP'ing and the convenience of a one-board quiver.

Boemix
26 posts
10 Jul 2020 12:50AM
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I also have a HN 8'0 4 in 1 and I notice that I must pump with my weight all the way back to start flying but then as soon as I'm flying I need to move forward to gain stability or it seems like the whole thing wants to do some kind of spinout.

Has somebody had this weird feeling?

Anyway I'm not complaining because I know there will be some trade-off to all that versatility. Actually if you add winging you have a 5 in 1 board!

Smidgeuk
70 posts
24 Aug 2020 3:38PM
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I find foiling the HN 8ft fine with Slingshot i99 (C) and i76 (B). A dedicated board would certainly be better obviously. The 4in1 needs more technique or wind for takeoff due to rail shape (so i wouldn't recommend for a beginner- although my daughter coped fine), and back foot strap position makes the foil position in the tracks very critical - so i now go strapless at rear (as does the Formula Foil world champ!!). I generally find my back foot ends up settling a bit further back than the rear strap holes. I really dont see any downside to rear strapless, only upside. Even some of the top racers run their back strap super long and tight so they can just hook their toes under it and move their foot around fore and aft
The 4in1 versatility is great. Not just the obvious, but also as a no wind toy for the kids to surf, sup, jump off and generally lurk around on (starlite construction and huge deck pad make that practical)



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"Hypernut 2018/2019/2020 foil box position/angle" started by themorb