Author Topic: Diy sup foil  (Read 130660 times)

Piros

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Re: Diy sup foil
« Reply #435 on: September 07, 2017, 01:59:43 AM »
Yeah good observation Charlie I have been looking at the same thing. The mast mounts really vary in the different brands . The new Naish Thrust mast is pushed right up to the back of the front wing but the Go foil is set back. I don’t have scientific answers but have done plenty of practical testing. We have found the Naish Thrust more stable in flight compared to the Kai GoFoil and also seems to carve and create more speed in the turns. The Kai Gofoil will still do the same but the sweet spot is much smaller. We have logged top speeds in excess of 30 mph on both foils free surfing on waves so lets leave front wing design out of it at the moment. (both rear wings are fairly similar)

Does moving the mast forward closer to the wing help with stability and control ? The Kai Gofoil does seem to pump a bit easier than the Naish Thrust , is that also from mast position back helping with leverage ? Getting back to the front wings they are very different , very hard to tell where the benefit comes from. I own both these foils and rate them highly. No answers I know but just sharing my time on the foil.

Where you see a massive difference in mast position on the fuselage is on the Naish wind foils and Slingshot wind foils compared to their surf foils. They are way back and so are the mast mounts to the boards. On windsurf foils the rear wing is way past the back of the board compared to a surf foils. This may be a good starting point to understand mast mounts on the fuselage as these guys have been at it a long time. Obviously the mast are back on the board because of wind power but the science of pushing the mast back on the fuselage to compensate will relate in some form to a Sup surf foil mast mount position on the fuselage.
« Last Edit: September 07, 2017, 02:23:06 AM by Piros »
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supuk

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Re: Diy sup foil
« Reply #436 on: September 07, 2017, 02:39:02 AM »
At the moment I'm trying to figure out the hole pumping thing as maximising this for dw is probably going to be key. I wish I had more foils to compare here to try and work things out a bit more. I did have a go foil on order but put it on hold till the new one is realised in Nov/Dec. My new mast and fuz will have adjustment between them so I can test a lot more variations. There are a huge number of things that can be adjusted and when you change one thing it's probably going to mean adjusting everything else's, it's incredibly complex compared to a surfboard!

I just had to jig up my new mast for the fuz mount, a bit ghetto but it's fairly accurate

Piros

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Re: Diy sup foil
« Reply #437 on: September 07, 2017, 03:57:20 AM »
Yes I've been lucky to test so many different foils. Interesting to see also Dave Kalama and Alex have been playing around with the new curved Maliko front wing with the Kai rear wing . Go Foil Aus say it will be available in 4 to 6 weeks can't wait to try that , supposed to be really good in smaller waves with heaps more pump and turning ability. Props to you for all your work you are doing on the foils they look really good and I'm keen to get a wedge like you posted on SB.
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supuk

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Re: Diy sup foil
« Reply #438 on: September 07, 2017, 04:44:38 AM »
Yea even now there is only a hand full of people over the uk with sup foils, I'm the only one I know of for about 100miles so not much options to test other than buying them all and I don't have the cash for that. I did have a go foil combo ordered but with pennies tight I have said wait till the new one. I do hear of a few others things in the pipe lines so maybe others to try too.

Flying has been in my blood since I was first given a knife and balsa wood at the age of 3 or 4 then building and designing model boats and aircraft all my child hood. I even had a rc hydrofoil back in the 80's. I then went on to fly full size aircraft around the age of 16-17 I first went solo in gliders with just under 20hours of training which is about 1/3 the normal person would have.

Being able to combine my love of the water with my love of flight has been huge for me and why I have been so pasonate about foiling.

PonoBill

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Re: Diy sup foil
« Reply #439 on: September 07, 2017, 07:14:12 AM »
Piros, the configuration of windsurf foils is not because of power, but because they use an existing Tuttle box for the fin.
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Piros

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Re: Diy sup foil
« Reply #440 on: September 07, 2017, 09:04:41 PM »
Ah yes of course plus that's where the back foot is.....so I assume they just slide the fuselage forward to help with lift.  How did your foil go in Hood river , I was talking to Rob from Aus about it he met you over there and said you were looking for a test pilot.
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supuk

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Re: Diy sup foil
« Reply #441 on: September 08, 2017, 12:44:01 PM »
So I allso just noticed it looks like the go foil has a lot shorter fuz behind the center point of the mast to the Takuma, is this correct piros and if so how does the naish compare?

Piros

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Re: Diy sup foil
« Reply #442 on: September 09, 2017, 10:11:25 PM »
Yes another good pick Charlie. The Go foil Fuselage is 80mm or 3.15" shorter between the wings , plus the mast is back 50mm or 2" . It's quiet a difference but you don't really feel it. There is a couple of pounds difference in the weight with the Naish being heavier but again you don't notice it surfing but you can feel it on the long paddles back out and carrying it to the car. The extra weight of the Naish also feels better on sketchy take offs but that could also be attributed to the longer fuselage.
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supuk

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Re: Diy sup foil
« Reply #443 on: September 09, 2017, 11:51:20 PM »
Cheers thanks for the pic I think this is perhaps the length of the fuz and position of mast could be the main effect to how efective the pumping works like when we had the comparison to pumping a bike and a skate board, basically it's finding what works for the frequency/harmonics that is posable to pump at comfatably.

Beasho

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Re: Diy sup foil
« Reply #444 on: September 10, 2017, 05:40:11 AM »
FYI:  Go Foil is 6.59 lbs with front and rear wing.

What is the Naish?

Piros

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Re: Diy sup foil
« Reply #445 on: September 10, 2017, 05:00:07 PM »
Go Foil Kai                   6.59 lbs

Naish Thrust Large     10.32 lbs

Sling Shot Surf model  11 .02 lbs

I'm guessing the Takuma will be closer to the Slingshot than the Naish , Charlie can you confirm.
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supuk

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Re: Diy sup foil
« Reply #446 on: September 11, 2017, 07:26:10 AM »
Yes the takuma is about 11.87

AlexFun

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Re: Diy sup foil
« Reply #447 on: September 15, 2017, 09:15:47 AM »
Interesting.  So the main difference between the original Takuma wing and your prototype is a thicker leading edge?  You did not change the surface area of the wing?

Leading edge and bottom profile area is almost the same.

Hi Supuk,
amazing what you are doing, i learned so much from you!

So you mainly shaped in more chamber?
@ Piros, maybe you can measure the profils of the Naish and Gofoil for comparison?

And i thought i could Supfoil with a 13mm flat Mantafoil, o dear, maybe in Nazare when McNamara and the town-in crews show up  ;-]

Alex

supuk

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Re: Diy sup foil
« Reply #448 on: September 15, 2017, 11:16:12 AM »
Interesting.  So the main difference between the original Takuma wing and your prototype is a thicker leading edge?  You did not change the surface area of the wing?

Leading edge and bottom profile area is almost the same.

Hi Supuk,
amazing what you are doing, i learned so much from you!

So you mainly shaped in more chamber?
@ Piros, maybe you can measure the profils of the Naish and Gofoil for comparison?

And i thought i could Supfoil with a 13mm flat Mantafoil, o dear, maybe in Nazare when McNamara and the town-in crews show up  ;-]

Alex


it was more about creating a larger radius on the leading edge to make the foil less sensitive to changes in AOA but this did add some camber.

There is defiantly a balance that needs to be found, we need lift at low speeds yet low drag when not flying. There is also a point were you can have to much speed so having a little extra drag at the higher speeds would be no bad thing.

I would be very interested to see the profiles of some other wings to see how they compare. you can make templates very quickly by putting some packing tape over the shape you want to profile and then making a very rough cardboard template and ten using bondo to make a impression to get the accurate shape.



supuk

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Re: Diy sup foil
« Reply #449 on: September 15, 2017, 11:18:24 AM »
I was working on a aluminum fuz but my shitty little mill was not really up to what I wanted to do so I have decided to do a basic composite one.

soon as I have figured out the cam for it I will cut it on the cnc and have a go at laying one up.