So @peter, what about that list from Nov 17 ? 
Man I love those numbers you told us : 50 mn of flight, that is amazing…
What is the motor brand?
waking up a month later…
But it makes it less stable on the roll axis.
Having it curved the other way: with the wing ends “higher” than the center would greatly improve roll stability… like self-righting foil…
Historically, kitesurf wing had the wing curved down to let you angle the foil much more to go upwind before the wing tips breach the surface. Breaching the surface used to mean assured wipe out. With all the recent development around surf foil, i’m seeing more and more flat wings, and advertisements (and videos) say they can breach the surface without wiping out.
For our use, we almost don’t angle the mast sideways, and as the motor has to stay in the water, we have no chance of breaching and room to install upward curved front wing…
I’m itching to test such a wing even before making a cleaner board 
anybody tried that? or am i overlooking something?
I have experienced several breach of surface in tight turn at high speed and every time it’s like an uncontrolled skid and I end up in the water.
I’ll tell you how these work as I have 2 of the surf variety coming from China 
No…I must disagree with this.
Having the wing ends higher than the central point would decrease stability as it introduces the roll factor.
If you look at the best surf wings, the tips of the main wing all point down as well as the stabiliser having an anhedral. The cheaper wings seem to be flatter as this makes the manufacturing process a LOT easier and cheaper.
As our setups improve and become lighter, you’ll find that guys will start to carve and that’s when the surf style wings will come in handy.
Hey @philgib, sorry forgot to add;
Here are two drive concepts that will definitely work:
- Loads of power for heavy and really fast riders: TpPower 5690 motor with 290KV, a 3/1 ratio gearbox from Neugart and a torqeedo p350 Ultralight propeller, both @10 and 12S (12S is close to harakiri at full throttle)
- Middle power with very thin motor pod: SSS 4092 with 600KV and a 6/1 ratio gearbox either by Reisenauer or Neugart and a 7 1/4 by 7 inch prop @10S
Both can easily be housed in an aluminium tube; off side thrust bearing is highly recommended, and double shaft sealings with oil in between!
As I said you can only reach that low power consumption when you want to fly with nearly zero stability. Maximum efficiency leads to zero stability. You have to find your own sweet spot for this.
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Awesome build Peter.
Are you still using the batteries from RC Technik.
I am also planning my efoil since I read your thread
Did a lot with 18650 batteries the last years. Will probably build a 12s pack out of the LG cells with cell level fuses.
When I read the consumption specs above, 2 h of flying should be possible with around 6 kg in batteries
Is there any way to contact you? Didn’t find a function here in the forum.
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you have to be registered for more than 24h (anti spam).
What is your motor and esc brand?
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Wow!! love your Pragmatik Design and Ideas - I think i start with your concept 
and with the “Loads of power” config (i have 93 kg)
Any Pointers where i can learn die aliminum stuff needed to build and witch winding on the motor (Starting your own webshop?)?
thanks und greetings from austria
I just looked it up because I’m interested in it too, and as he said, it’s the 290Kv version, it has to be the 10Y one…
Greetings from Austria…
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Hi Thanks for the fast reply!
He who can read is better of (Wer lesen kann ist klar im Vorteil ) I could have figured that out myself …
Have you found links to the gearbox?
I found the Prop and is 2 bladed is this OK? (Spare propeller v10/p350 - Torqeedo)
Have you started your build?
Sorry for the late reply, I was on holiday for kitesurfing. So not much progress on my build. 
I haven’t found the gearbox, but for me it’s not critical at the moment, because I’m only looking for parts for my 2nd version, in case my 1st one does fail completely. 
Yes I’m allready building and I’m almost done. 
(I hope so)
My concept is a “Directdrive-Dry-Outrunner-Jetdrive-Hybrid” (thaha… I love that Word) with 83100 Watercooled 180KV Outrunner and 80mm prop built in one torpedolike tube.
Thrust tests look promising (allmost unable to hold it back) but I’m a bit concerned about “The Heat Problem” allmost all dry-outrunners have. 
We will see.
Greedings
i would love to see a foto of this construction sound very interesting
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I will post one soon…
Hi @seamoty ,
really cool idea, but to be honest, the feet in water create beyond 6-8knots very high drag. If you manage to get foiling, it’s always a matter of a little up and down and if you get in contact with water streaming with 15-20knots at your feet might be even painful.
