Electric Hydrofoil/E-Foil

Boats, Jet Skis, Kayaks etc., including hovercrafts
Hiorth   1 W

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Re: Electric Hydrofoil/E-Foil

Post by Hiorth » Sep 01 2017 11:30am

We use PLA. Seems to bond well to epoxy as well. We know it's controversial, but we believe PLA to be a better material than abs (at least on cheap printers without heated chamber etc). It's a lot easier to work with, low shrink, good layer adhesion (almost all 3d prints break between the layers).

Should be enough to sand away the layer lines in the PLA, with 100 grit paper then bond the fiberglass/carbon directly to the 3d print surface. Don't think it's needed with a priming layer.
Last edited by Hiorth on Sep 02 2017 1:14pm, edited 1 time in total.

kiter_UK   10 mW

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Re: Electric Hydrofoil/E-Foil

Post by kiter_UK » Sep 01 2017 11:44am

Strength Ok I take it?

No problems with heat?

I was reading that pla less good with higher temperatures and tends to decompose over time.

(No experience at all with 3d printing so keen to not make rookie mistakes)

Hiorth   1 W

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Re: Electric Hydrofoil/E-Foil

Post by Hiorth » Sep 02 2017 10:43am

kiter_UK wrote:Strength Ok I take it?

No problems with heat?

I was reading that pla less good with higher temperatures and tends to decompose over time.

(No experience at all with 3d printing so keen to not make rookie mistakes)
We used a combination of nylon sls (waterproof high load parts) and pla (prop and duct). Heat is not an issue as the parts are below the water surface.

dirkdiggler   10 kW

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Re: Electric Hydrofoil/E-Foil

Post by dirkdiggler » Sep 02 2017 1:37pm

Here's a great test of material strength that goes along with the e-foil:


Pc or PLA seems to hold up the best.

Vincentbraillard   100 µW

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Re: Electric Hydrofoil/E-Foil

Post by Vincentbraillard » Sep 03 2017 8:56am

Hello everybody.
Like everybody i want to fly over the water. So I decide to build my own system. The only thing I want is to use a outrunner because of the cost of the reduction.

I already have done a lot of test of motor and propeller using my paddle board.

Here is the drawing of my futur system. I will use a crazyfoil, a outrunner motor and esc from alienpower and a 8s 20ah battery.

Feel free to comment it.
Attachments
rsz_assemblagepropulseur.jpg

nanni   1 mW

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Re: Electric Hydrofoil/E-Foil

Post by nanni » Sep 03 2017 9:59am

Vincentbraillard wrote:Hello everybody.
Like everybody i want to fly over the water. So I decide to build my own system. The only thing I want is to use a outrunner because of the cost of the reduction.

I already have done a lot of test of motor and propeller using my paddle board.

Here is the drawing of my futur system. I will use a crazyfoil, a outrunner motor and esc from alienpower and a 8s 20ah battery.

Feel free to comment it.
List of components, please. Which motor and kv, propeller (in drawing it seems solas propeller or 2-3 hp stroke outboard propeller). What kind of test you have done on your paddle board? Have you some result? or video ? Thanks

Just2807   10 W

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Re: Electric Hydrofoil/E-Foil

Post by Just2807 » Sep 03 2017 12:34pm

I still dont get how to properly cool an outrunner watersealed without adding any liquids/semiliquids and some kind of a heatsink for this purpose. And i still would be very suspicious about temps and losses. I guess using overspeced motor would work but.... size? Can he use "emtpy space" (in this case just before motor) for a small water cooling unit? I dont know how those work on this small kind of engines or how big they are but.... ?

AS5   1 µW

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Re: Electric Hydrofoil/E-Foil

Post by AS5 » Sep 03 2017 1:43pm

Hello together,

I'm new in this forums and since i saw an electric jetsurf on my trip in croatia interested in building my own one. Because of the power issue i want to build a jetfoiler. Saw all the pacificmeister videos but there are still a lot of questions opened.
How important is the board size? I have an old wind surfboard. Can there be a water resistence issue?
Whats the top speed you can get with the hiorth setup?
Sorry for the questions if they were answered before and thank you for you help.

Marko

nanni   1 mW

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Re: Electric Hydrofoil/E-Foil

Post by nanni » Sep 03 2017 3:41pm

motore outrunner2.jpg
the flange will be made of anodised aluminium and I change prop with solas prop
the flange will be made of anodised aluminium
motore outrunner2.jpg (241.03 KiB) Viewed 2002 times
Immagine.jpg
Immagine.jpg (59.21 KiB) Viewed 568 times
This is what I think: Anodised aluminium is a good thermal conductor and an electric insulator; the flange directly screwed to the outrunner motor may possibly cool the engine by heat exchange with the outside water, as well as the anodised aluminum tube made as close as possible to the outrunner rotor will eliminate the air for a quicker thermal exchange with the outside water; (the air is a thermal insulator) so doing there will be really little air inside.
Your comment are welcome

Just2807   10 W

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Re: Electric Hydrofoil/E-Foil

Post by Just2807 » Sep 03 2017 4:11pm

AS5 wrote:Hello together,

I'm new in this forums and since i saw an electric jetsurf on my trip in croatia interested in building my own one. Because of the power issue i want to build a jetfoiler. Saw all the pacificmeister videos but there are still a lot of questions opened.
How important is the board size? I have an old wind surfboard. Can there be a water resistence issue?
Whats the top speed you can get with the hiorth setup?
Sorry for the questions if they were answered before and thank you for you help.

Marko
From a kitesurfing perspective (i use twintip), more board surface and less rocker (curvature of a board), less power needed for planning. But here, i just think u need certain speed which foil needs to get enough lift. Hiorth said he keeps 1/2-2/3rd of gas till he lifts off, then 1/3rd during foiling, he didnt specify amount of amps he was pulling (they got wrong ampmeter or nonworking1, not sure).

U can check jet surfboard threads for specific questions. But i dont think it matters too much since we focusing strictly on foil here.

Scroll through the thread, lots of info and some hard working guys giving precious info for free. Its mostly hit n miss but some did awesome.
Greetings from Cro ;)

Vincentbraillard   100 µW

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Re: Electric Hydrofoil/E-Foil

Post by Vincentbraillard » Sep 03 2017 4:37pm

Hello.

Esc
http://alienpowersystem.com/shop/esc/bo ... at-esc-be/

Motor
http://alienpowersystem.com/shop/brushl ... 0kv-3300w/

Battery
https://hobbyking.com/en_us/multistar-h ... tore=en_us is a solas effectively

I have done some test with a outrunner running directly in the water and it work perfectly even if the magnets become a little bit red

To cool.my motor, the piece in the middle will be in copper and will cool the stator by conduction!

Concerning the efficiency, it will be the same compare to a inrunner with a reduction but the price....much lower
Attachments
rsz_20170810_200404.jpg
rsz_20170810_200404.jpg (226.2 KiB) Viewed 570 times

Just2807   10 W

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Re: Electric Hydrofoil/E-Foil

Post by Just2807 » Sep 03 2017 6:19pm

Vincent that looks great! Good luck with cooling, i like the idea, wish it works!! Would solve a lot of problems.
Also, u are running around 5000 rpm at the propeller? (8s on 170 kv)

Vincentbraillard   100 µW

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Re: Electric Hydrofoil/E-Foil

Post by Vincentbraillard » Sep 04 2017 3:43am

The propeller is given for a 6000rpm motor with a reduction ratio of two. The speed of 5000 rpm is given for a free running motor so I thing I Will fall around 3000 rpm with charge

I will put a eagle tree V4 with current and rmp log so I can tune my system!

keith..9   1 µW

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Re: Electric Hydrofoil/E-Foil

Post by keith..9 » Sep 04 2017 2:25pm

hi guys, its great to see the progress of the hydrofoil, its brilliant,
i started off planing to build a jet surf board, but the foil option seems way cooler, to fly on the surface, sounds so nice,...soon hopefully,
anyway i've been over heating my brain for a few months now, and its really helped seeing everyone thinking in a similar line,
I starting to source parts now. For the oval keel i was looking for oval extruded alloy, even from a heavy duty car roof rack or sometimes you see oval venetian blinds on the outside of modern buildings, if I find a supplier ill put up a link,
anyway, has anyone had any results trying one of these prop assemblies, there is a few pitch options and diameters available
https://www.aliexpress.com/item/Dia-110 ... ae2bmpIbDN

also I found a 400 Kv motor that looks interesting (400kv x 38v=15200/5 =3040 rpm) here:
https://www.tfl-hobby.de/Motore--Halter ... kv-8y.html

for the planetary gearbox either a parker 5 to 1 or neugart ple 5 to 1
Im just trying to work out which of the propeller options is the one to go for, and as i have not ordered the motor yet do they rotate clock wise, hope you guys can help, as my brain over heats easily, hello from Ireland, Keith 8)

waterfox   1 mW

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Re: Electric Hydrofoil/E-Foil

Post by waterfox » Sep 04 2017 4:13pm

Hi All,

I had some success this weekend with my build. I was ripping around the bay for about 25 minutes and used up about half of my 12S 16Ah pack. I found it quite a bit harder to ride while trying to maintain throttle and balance, with all the force coming from the bottom of the mast. I eventually broke my PLA prop and had to come back to shore. Time to print with thicker blades and more infill.

SSS 56104 500kV
Neugart PLE40 i=8
12S 16Ah: 2X Tattu Plus 6S 16Ah.
3D printed 15.8mm prop designed for 14 knots at 2750RPM.

Good luck to all you other builders! Very cool experience to rocket around on a little foil board.
Attachments
DSC_0482_2.jpg
DSC_0020_e2.jpg

Gege2000   10 mW

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Re: Electric Hydrofoil/E-Foil

Post by Gege2000 » Sep 04 2017 9:41pm

waterfox wrote:I had some success this weekend with my build. I was ripping around the bay for about 25 minutes and used up about half of my 12S 16Ah pack. I found it quite a bit harder to ride while trying to maintain throttle and balance, with all the force coming from the bottom of the mast. I eventually broke my PLA prop and had to come back to shore. Time to print with thicker blades and more infill.
SSS 56104 500kV
Neugart PLE40 i=8
12S 16Ah: 2X Tattu Plus 6S 16Ah.
3D printed 15.8mm prop designed for 14 knots at 2750RPM.
Good luck to all you other builders! Very cool experience to rocket around on a little foil board.
Wohoho! Congrats! :D
It looks a very clean build. Would you send some detail pictures?
Best regards.

Jimmy22   100 µW

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Re: Electric Hydrofoil/E-Foil

Post by Jimmy22 » Sep 04 2017 10:22pm

waterfox wrote:Hi All,

I had some success this weekend with my build. I was ripping around the bay for about 25 minutes and used up about half of my 12S 16Ah pack. I found it quite a bit harder to ride while trying to maintain throttle and balance, with all the force coming from the bottom of the mast. I eventually broke my PLA prop and had to come back to shore. Time to print with thicker blades and more infill.

SSS 56104 500kV
Neugart PLE40 i=8
12S 16Ah: 2X Tattu Plus 6S 16Ah.
3D printed 15.8mm prop designed for 14 knots at 2750RPM.

Good luck to all you other builders! Very cool experience to rocket around on a little foil board.

Making life a bit harder on the dwarfcraft board :) , maybe program the esc or throttle control for less sensitivity , Pacific Meyster said the key is to get up to speed before popping the foil, i imagine the NF2 slingshot foils are lifting at about 15 kmph or so , but then it depends if you are still only at 1/4 throttle it will eat you alive when you pour on more throttle hehe. A higher pitch or lower diameter will take away some of the enormous thrust you have, every 12mm off the diameter is worth aprox 25mm of pitch as a very rough estimate as far as load. I would take some mm off the diameter (just 5mm increments) so it has less thrust but near the same basic speed allowing for slip factor changing by a few percent.

The board is an interesting one as you need enough thrust to get the board planning before you reach foiling speeds so you may find a limit where you lose too much thrust to make that happen. We found 30kg of thrust is required for our converted course racing boards by using a load cell to measure the drag all the way on to the foil. Put the best grease available into that gearbox and keep an eye on it .

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parabellum   10 MW

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Re: Electric Hydrofoil/E-Foil

Post by parabellum » Sep 04 2017 10:25pm

nanni wrote: anodised aluminum tube made as close as possible to the outrunner rotor will eliminate the air for a quicker thermal exchange with the outside water;
You may want to choose non conductive material around a rotating magnetic field or have a gap, big enough to leaking magnetic field not reach conductive static cylinder, generating recirculating current. Think magnet through cooper pipe trick.

kiter_UK   10 mW

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Re: Electric Hydrofoil/E-Foil

Post by kiter_UK » Sep 05 2017 12:19am

SSS 56104 500kV
Neugart PLE40 i=8

@waterfox, @hiorth

Any advise for matching 10mm SSS shaft to 8mm neugart?

beonwater   1 mW

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Re: Electric Hydrofoil/E-Foil

Post by beonwater » Sep 05 2017 1:44am

waterfox wrote:Hi All,

I had some success this weekend with my build. I was ripping around the bay for about 25 minutes and used up about half of my 12S 16Ah pack. I found it quite a bit harder to ride while trying to maintain throttle and balance, with all the force coming from the bottom of the mast. I eventually broke my PLA prop and had to come back to shore. Time to print with thicker blades and more infill.

SSS 56104 500kV
Neugart PLE40 i=8
12S 16Ah: 2X Tattu Plus 6S 16Ah.
3D printed 15.8mm prop designed for 14 knots at 2750RPM.

Good luck to all you other builders! Very cool experience to rocket around on a little foil board.
Nice! Amazing that you got up on this small board. On the first picture it looks like you have the cables to the motor outside the mast, did you ride it like that?
Also cool if it works with these type of hydrofoils wings as I assume that they are more high aspect than the Liquid Force wings used by pacificmeister.

Gege2000   10 mW

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Re: Electric Hydrofoil/E-Foil

Post by Gege2000 » Sep 05 2017 1:45am

kiter_UK wrote:SSS 56104 500kV
Neugart PLE40 i=8
@waterfox, @hiorth
Any advise for matching 10mm SSS shaft to 8mm neugart?
In my Neugart PLE40/i=8, there is a ring that can be removed.

kiter_UK   10 mW

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Re: Electric Hydrofoil/E-Foil

Post by kiter_UK » Sep 05 2017 1:58am

My ring was 6mm, leaving 8mm when removed. :(

Could swap motor for 700kv with 8mm shaft (from my 650kv with 10mm) but wondering how easy to reshape either part, without assymetry.

I think @hiorth ran the motor at speed and filed down...???

Tried taking neugart apart but think coupling is glued or heat-shrunk in place. Makes for a very awkward lathe or drill.

So I'm left thinking of either Hiorth method or taking shaft out of motor and getting lathed down by a pro.

Gege2000   10 mW

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Re: Electric Hydrofoil/E-Foil

Post by Gege2000 » Sep 05 2017 3:18am

kiter_UK wrote:My ring was 6mm, leaving 8mm when removed. :(
My SSS56104-kv500 has a 8mm shaft.

Hiorth   1 W

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Re: Electric Hydrofoil/E-Foil

Post by Hiorth » Sep 05 2017 8:41am

We grinded the shaft down while the motor was running. Our input without the sleeve inside was about 9mm. Would recommend to get an 8mm shaft 56104 (they are avaliable on ebay). Took at least 2 hours to grind it down.

Or remove the shaft and use a lathe... but we did not have that type og equipment :D

kiter_UK   10 mW

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Re: Electric Hydrofoil/E-Foil

Post by kiter_UK » Sep 05 2017 10:22am

Thanks all. Gutted I ordered a 10mm shaft.

More haste, less speed! (More cost!)

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