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Another foil to raceboard marrige .

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Created by Imax1 4 months ago, 31 Jan 2019
Imax1
VIC, 1943 posts
31 Jan 2019 6:23PM
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Taking on ZoltanL's idea to join a foil to a race board.
Thought id show how I made it.
All the parts.
The wings are Slingshot hover foils . Nice and big.



The mast is from a foiling sailboat , Waspt. ( I think that's how to spell it ) . I used this because its stronger than a wind foil for heavy me and heavy board.
Made some inserts to be able to bolt to fuselage .



Milling the profile in plastic blocks to support the mast.


Plastic covers over CB slot .
The small gap at the front is so the mast can pivot back and come out if I hit something solid without wrecking the board . Still have to strip two 8mm barrel nuts.



Mast cassette assembly . EVA foam on sides for a snug fit .( thanks olskool )



Top plate











Mast is 850 cm high.
Fuselage is long to match the board. That's my theory anyway . I may shorten it .
1.2m total length.
6.7 kg complete.







Around fifteen hours . Hope it works ! It will at least make one hell of a CB.




Maybe I need a helmet , I have no idea of what I'm doing .

ZoltanL
ACT, 124 posts
31 Jan 2019 7:00PM
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Imax1, that looks solid as!!! Great stuff

Mobydisc
NSW, 8565 posts
31 Jan 2019 7:20PM
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Can you document how this goes in action?

The old windsurfers with fixed centreboards experienced what was uncontrolled lift from the centre. I felt this too later with an RRD board with a bolt in centreboard and a race sail. The board rose up from the centre as it started planning. It was scary.

NelsonFoils
177 posts
31 Jan 2019 6:54PM
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Nice workshop !

Foil must be 30-40 more in the back , no ?

CJW
NSW, 1538 posts
31 Jan 2019 10:26PM
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Stupid question, have you foiled before? I only ask because everything I've learned foiling tells me that is going to be very tricky to sail. Make sure you film it

Also, props on the fab work, tip top

Adam555
WA, 113 posts
31 Jan 2019 8:52PM
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Great fabrication work really keen to see how it goes

olskool
QLD, 1365 posts
1 Feb 2019 4:37AM
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Crankin engineering there mate! As usual, done to the "Imax1". Hahaha. Get some footage of the FLYIN IMCO. Keen to n hear report of it in action. Filth dude!!!! Im with Nelson, mast should be further back in CB slot? No helmet needed. Just have your biggest kahunas along with ya. YEEEEWWWW!!!

olskool
QLD, 1365 posts
1 Feb 2019 4:46AM
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Moby, even a new RB will foil n rise up on the CB alone. If all forces equal its like doing a wheelstand. Can be held for a few seconds.But without the wing,things go south pretty darn quick. Have had many stacks tryin to control this.

CAN17
230 posts
1 Feb 2019 3:39AM
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Nice work. I'm impressed with that mast head, its defiantly ready for a heavy weight now!

Not sure if a race board is the best option for foiling though. I bet you could make a foil board out of a old race board by cutting it shorter and shaping it the way you want it. Seen a guy do this for his electric hydrofoil. Might want to do it with a slightly wider board.
www.google.com/url?sa=t&source=web&rct=j&url=https://www.instructables.com/id/Building-an-ELECTRICAL-Hydrofoil-Part-12/&ved=2ahUKEwjEu6S94pjgAhWC3oMKHdh2CHwQFjACegQIARAB&usg=AOvVaw0u0ENJsWIzh8Ca9HwJjHZI

Ps. It's not too late. But get a video of this thing first

igetwind_com
1 posts
1 Feb 2019 4:01AM
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Great!! remind me of this:

Imax1
VIC, 1943 posts
1 Feb 2019 6:16AM
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Select to expand quote
CJW said..
Stupid question, have you foiled before? I only ask because everything I've learned foiling tells me that is going to be very tricky to sail. Make sure you film it

Also, props on the fab work, tip top


No never foiled , how hard could it be

Imax1
VIC, 1943 posts
1 Feb 2019 6:25AM
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Select to expand quote
NelsonFoils said..
Nice workshop !

Foil must be 30-40 more in the back , no ?






I have theories about that , no idea , just theories .
Because the mast track is so long I could always get the sail to foil distance right. Just more board overhang front and rear.( more balanced ) ?
I mounted the front foil as close to the foil mast to get it back further.

Which brings a question , what is the correct distance between sail mast base to front of foil wing ?

I have the complete foil so will be using it the normal way , just thought it might be groovy on a RB.
Too much time on my hands and no wind.

ps: why did I not put this in the foiling section

Paducah
365 posts
1 Feb 2019 5:49AM
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Select to expand quote
Imax1 said..
Which brings a question , what is the correct distance between sail mast base to front of foil wing ?


Um... Isn't this one of the questions one asks before fabricating everything?

As a regular denizen of foiltown next door, 105-120 cm from front bolt to mast base center is a decent idea of the range. Depends on foil, wing size and a bunch of other stuff but that should be a start.

I, too, share some concern about all that mast on a relatively narrow board but I'm just some guy on the internet. Just remember: don't let go of the boom whatever happens. Nice fab work. Good luck!

515
196 posts
1 Feb 2019 6:05AM
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Awesome work Imax1
Looking forward to hearing how you "fly"
Cheers Greg

olskool
QLD, 1365 posts
1 Feb 2019 8:35AM
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Ive not foiled. But surely each board n application would have different criteria to find its sweet spot. Mastlength wise, doesn't the rider control the height he flies it at? Only issue is running aground(mast too long) n clearing the expected waves or chop?(mast too short) More front leg pressure keeps it low.
Regards position of foilmast in CB case. CE of sail is related to board design n normally aligns between front n rear straps. Therefore if foil is more rearward less front leg pressure is reqd (coz of looong nose n weight) to counteract the foils tendancy to breach. Maybe it should be somewhere near front foot straps? That ol vid posted highlights it. Foil mast is raked back. Wings are closer to frontstraps. Just my rambling thoughts... Keen to see the outcome of Franken-foil

Imax1
VIC, 1943 posts
1 Feb 2019 8:57AM
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That's why I wanted to know the ideal kind of distance between front of foil and sail mast . Because the board is sooo long and flat rockered and the mast track also very long , I'm positive I can get this distance correct with room to spare . Would this not mean I just have to move me and the sail more central ?
Not sure about length of mast and how that works , I just picked average like the NP alloy . I can easily shorten it but not lengthen .

Imax1
VIC, 1943 posts
1 Feb 2019 9:26AM
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Select to expand quote
Paducah said..

Imax1 said..
Which brings a question , what is the correct distance between sail mast base to front of foil wing ?



Um... Isn't this one of the questions one asks before fabricating everything?

As a regular denizen of foiltown next door, 105-120 cm from front bolt to mast base center is a decent idea of the range. Depends on foil, wing size and a bunch of other stuff but that should be a start.

I, too, share some concern about all that mast on a relatively narrow board but I'm just some guy on the internet. Just remember: don't let go of the boom whatever happens. Nice fab work. Good luck!


Is that distance from the front bolt of the wing or the Tuttle box ?

olskool
QLD, 1365 posts
1 Feb 2019 9:36AM
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Yep with foilmast forward youd have to stand further forward n mast car further forward. Have a look at Zoltans setup. Looks about right. Foils can point much higher than a finned setup. So disregard having mastcar forward at all. Id think 2/3 back for mastcar n leave it there. Even in fin mode you can point ok from that position. Then you are also in the zone to use footstraps, enabling you to lift or push on board until you find its sweet spot. Length of foilmast should be sweet as youve got it.Another thing, is normal fin even reqd? Foilmast n wings doin all the work. Just from a "looks right" perspective foilmast should be 2/3 back in CB case??? All just my guesstimations. Wish i could come play...

olskool
QLD, 1365 posts
1 Feb 2019 9:58AM
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Imax1, think of it this way. You dont wanna look like your sailing a bloody Sabot. Its an RB. Sail it like its a Top Fuel Drag Car. All that bonnet swingin in the breeze. Stance just like when shes fully powered up on a broad reach. Yeeeewwww!!!!


Select to expand quote
Imax1 said.. Mast is 850 cm high.
Maybe I need a helmet , I have no idea of what I'm doing .

850cm???? Helmet not needed coz Launching will be the issue....

Paducah
365 posts
1 Feb 2019 8:18AM
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Imax1 said..

Is that distance from the front bolt of the wing or the Tuttle box ?


For most windfoils - front tuttle screw. I had no idea with the first board I used for foiling (*board Freeformula) and had to learn by trial and error that the mast base had to be all the way back in the track. The trial and error part was a board that refused to get off the water if I was in the straps unless I literally jerked it out of the water. Didn't help with the learning process. When I bought a real foil board, the mast base ended up pretty much in the middle of the track and the board would come out of the water with just a nudge. So much better.

I've used four different windfoils on my foilboard and most are in with a few cm of each other (108-112). The outlier is a real lifty race style foil which I have to go about 5cm more forward to keep it manageable.

Image from a French foiling forum. A few fellows will put this in their signature along with their measurements. Note the A dimension.



Good luck and have fun. The first time you get out of the water and everything gets quiet is memorable.

PS Some more stuff from that forum ( www.windsurfing33.com/forum/viewtopic.php?f=42&t=113110&start=45 )

CJW
NSW, 1538 posts
1 Feb 2019 11:16AM
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A super simple way to look at it is this. The main lift component is the front wing, basically...roughly....when in stable flight you are going to have that front wing in the middle of your stance. Looking at your setup that puts you way forward. Then look at the post above for a rough mast position relative to the foil. Yeah all foils are different and you're going to have to muck around but this we'll get you within a 100mm zone either way for foot strap and mast foot position.

Imax1
VIC, 1943 posts
1 Feb 2019 3:23PM
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Select to expand quote
CJW said..
A super simple way to look at it is this. The main lift component is the front wing, basically...roughly....when in stable flight you are going to have that front wing in the middle of your stance. Looking at your setup that puts you way forward. Then look at the post above for a rough mast position relative to the foil. Yeah all foils are different and you're going to have to muck around but this we'll get you within a 100mm zone either way for foot strap and mast foot position.


By those calculations my back foot will be in the pointing strap and no strap for my front foot. Mast about two thirds forward.
Hopefully tomorrow ill get a go .

jusavina
QLD, 1189 posts
1 Feb 2019 4:16PM
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Select to expand quote
Imax1 said..

CJW said..
A super simple way to look at it is this. The main lift component is the front wing, basically...roughly....when in stable flight you are going to have that front wing in the middle of your stance. Looking at your setup that puts you way forward. Then look at the post above for a rough mast position relative to the foil. Yeah all foils are different and you're going to have to muck around but this we'll get you within a 100mm zone either way for foot strap and mast foot position.



By those calculations my back foot will be in the pointing strap and no strap for my front foot. Mast about two thirds forward.
Hopefully tomorrow ill get a go .


Please make sure you film it!!!Charge the camera tonight

Imax1
VIC, 1943 posts
1 Feb 2019 4:58PM
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Please make sure you film it!!!Charge the camera tonight



I don't have a water camera.
But it is nice that people want to see me eat dirt on my first foiling attempt.
Even if it does work I'm sure I'm going to make it look bad.
Any last tips for a gumbi ?

jusavina
QLD, 1189 posts
1 Feb 2019 5:15PM
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Imax1 said..

Please make sure you film it!!!Charge the camera tonight




I don't have a water camera.
But it is nice that people want to see me eat dirt on my first foiling attempt.
Even if it does work I'm sure I'm going to make it look bad.
Any last tips for a gumbi ?


Remembering my first attempt a foiling, you only drink water I'm actually curious to see the balance of the board when foiling.My advice with your set up is that you should make sure the rake of the foil is set in a way that the nose of the board goes up (if that make sense) just to avoid a massive nose dive.The pic below is amplified of course:



AusMoz
QLD, 1076 posts
1 Feb 2019 5:33PM
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Select to expand quote
Imax1 said..

Please make sure you film it!!!Charge the camera tonight




I don't have a water camera.
But it is nice that people want to see me eat dirt on my first foiling attempt.
Even if it does work I'm sure I'm going to make it look bad.
Any last tips for a gumbi ?


No eating dirt! Just enjoy it! Good to see R &D on this! Have fun.

Paducah
365 posts
1 Feb 2019 9:16PM
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Select to expand quote
jusavina said..

Imax1 said..


Please make sure you film it!!!Charge the camera tonight





I don't have a water camera.
But it is nice that people want to see me eat dirt on my first foiling attempt.
Even if it does work I'm sure I'm going to make it look bad.
Any last tips for a gumbi ?



Remembering my first attempt a foiling, you only drink water I'm actually curious to see the balance of the board when foiling.My advice with your set up is that you should make sure the rake of the foil is set in a way that the nose of the board goes up (if that make sense) just to avoid a massive nose dive.The pic below is amplified of course:




Good point - about 3-4 degrees. You can use a cell phone app as a digital level if you phone is capable.

Another thing your phone is likely capable of- a friend taking pics/videos from the beach. Try short hops at first. You may want to look at Slingshot's Foil Academy online or Sam Ross on Youtube for some pointers.

Imax1
VIC, 1943 posts
2 Feb 2019 4:36PM
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Had my first go today , bloody awesome
Conditions , fresh water lake , flat , super gusty , swirly 2 to 12 kts ish , 9.4 V8.
Now I know why You sadists wanted footage .
Got half a dozen flights with four good crashes ,over the back , front and each side , got em all covered.
Below take off speed the board doesn't feel much different but I'm sure it's faster , points higher , but is much slower tacking and jibing. I have to stand right on the edge of the board .It also makes quite a loud humming noise just before lift off and stops when up in the air.
First attempt nothing happened until I leant back and it came straight up . This is where I sh.t myself and did everything wrong . Bent my feet , hung off the back and outboard for safety and sheeted in . It's amazing how quick a super long RB can slice into the wind ,... crash.
Keep talking to myself , when things happen stand over the board and lean forward , this is hard to do. It's not normal.
Next couple runs I could keep the board about a foot off the water with the back just tapping the water. 20 then about 50 metres , totally happy at this point . This is quite comfortable and slippery , I think it's because the rear fin is holding everything in line.
The next one freaked me out , Flying along about a foot off the water , ( I can say that now ) , with the tail clipping the water I thought I'm ready for more air so I pushed hard on my back foot to get more angle and it went nuts . I'm sure your not meant to see the front foil while sailing a foot above the water with the board at 45 deg. Talk about air ! Big crash over the front.
The next couple , I got a bit better , once the rear fin is out of the water it's like balancing on a exercise ball. Very short flights ,one crash and one save.
Its a strange feeling and I want more.
Its like learning all over again , the hardest part is to lean forward when it gets scary.
Better wind tomorrow, I'd like to use a smaller sail.
Not that I can compare to a proper foil board but i think It will work fine . It ramps up speed beautifully and with some of the rear fin in the water it stays in a straight line.
One tiny piece of advice I can give is use an older sail , I'm lucky I didn't wreck mine.

seanhogan
3033 posts
2 Feb 2019 4:14PM
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awesome !! good on you for experimenting and sharing !! Thanls !! (still would like to see a video !)

ZoltanL
ACT, 124 posts
3 Feb 2019 4:52AM
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Select to expand quote
Imax1 said..
Had my first go today , bloody awesome
Conditions , fresh water lake , flat , super gusty , swirly 2 to 12 kts ish , 9.4 V8.
Now I know why You sadists wanted footage .
Got half a dozen flights with four good crashes ,over the back , front and each side , got em all covered.
Below take off speed the board doesn't feel much different but I'm sure it's faster , points higher , but is much slower tacking and jibing. I have to stand right on the edge of the board .It also makes quite a loud humming noise just before lift off and stops when up in the air.
First attempt nothing happened until I leant back and it came straight up . This is where I sh.t myself and did everything wrong . Bent my feet , hung off the back and outboard for safety and sheeted in . It's amazing how quick a super long RB can slice into the wind ,... crash.
Keep talking to myself , when things happen stand over the board and lean forward , this is hard to do. It's not normal.
Next couple runs I could keep the board about a foot off the water with the back just tapping the water. 20 then about 50 metres , totally happy at this point . This is quite comfortable and slippery , I think it's because the rear fin is holding everything in line.
The next one freaked me out , Flying along about a foot off the water , ( I can say that now ) , with the tail clipping the water I thought I'm ready for more air so I pushed hard on my back foot to get more angle and it went nuts . I'm sure your not meant to see the front foil while sailing a foot above the water with the board at 45 deg. Talk about air ! Big crash over the front.
The next couple , I got a bit better , once the rear fin is out of the water it's like balancing on a exercise ball. Very short flights ,one crash and one save.
Its a strange feeling and I want more.
Its like learning all over again , the hardest part is to lean forward when it gets scary.
Better wind tomorrow, I'd like to use a smaller sail.
Not that I can compare to a proper foil board but i think It will work fine . It ramps up speed beautifully and with some of the rear fin in the water it stays in a straight line.
One tiny piece of advice I can give is use an older sail , I'm lucky I didn't wreck mine.

Loving your work Imax1!
Now you know how good & exciting - radical even? - it feels using a foil on a RB. Agree it's a bitch to turn, but everything else is $&@?! awesome

Really hoping this will catch on and we can all meet up somewhere central for a few beers & laughs - and to test our gear against each other's. Just not for another 5-10 days as I'm just out of hospital from sudden onset of acute vertigo (not from foiling lol) and ordered to rest & not drive or sail for that time. So I'm foiling the RB through you for a while Imax1
z

Windbot
76 posts
7 Feb 2019 8:16AM
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This is super interesting, keep the updates coming!



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"Another foil to raceboard marrige ." started by Imax1