Complete DIY Cheap Austrian Build

[levitater]

Hi guys,

I am a mencanical-engineering student from Austria.
After hours of scrolling and reading through the whole efoil.builders forum, I´ve now started my 100% DIY hydrofoil project. My build will be very slow, but I would like to give you some insights into my progress.

My main intention is to build an electric foil with the lowest costs possible. To achieve this goal, I will try to do as much as possible by myself.

Because of the fact, that I am currently attending university, my budget is very tight. So I would like to ask if anybody has some “leftovers” from their previous builds, that are intact, but not used anymore. I am at the very beginning of this project, so I think that nearly everything that I can get would be an improvement for me. For sure, I would pay for these parts!

After reading hours through your posts, I think that I have now figured out my setup (Unless I find some used parts):

Foil: DIY Hydrofoil + Board
Motor: AP 80100 (https://alienpowersystem.com/shop/brushless-motors/c80100-outrunner-brushless-motor-80kv-7000w/)
ESC: Flipsky High Current ESC (https://flipsky.net/collections/electronic-products/products/high-current-fsesc-200a-60v-base-on-vesc6)
Battery: 2 serial batteries 20000mah for 12s (https://hobbyking.com/de_de/turnigy-high-capacity-battery-20000mah-6s-12c-drone-lipo-pack-xt90.html?queryID=8f7b169a85d556d7ad56ed535929b8c6&objectID=78412&indexName=hbk_live_magento_de_de_products)

So I started a week ago with building my Hydrofoil:

As you can see, I started by designing my foil in Creo Parametric. The dimensions are very similar to the Levitatz Foil.
The two wings were form glued in my fathers workshop and afterwards sanded down to the profile, that I printed at airfoiltools.com. Afterwards I added two layers of 100g/m^2 fiberglass and epoxy.
The mast has a milled wood core which is laminated with 160g/m^2 carbopn fiber and epoxy.
The fuselage is also Carbon a carbon fibred woodcore.

The next step will now be to sand the last layer of epoxy down, and then screw all the parts together.
For an extra strenght at the connections, I have 3d-printed molds with will be poured with epoxy.
The mast already has some free space for the cables.
Finally there will also be a gloss coat over the finished foil.

I would be very happy if anybody would sell me some of their spare parts or would give me some useful tips

[levitater]

So, after long long time, I finally finished my foil.
I´m very satisfied with it, and I look forward to test it with my kite.

[Mislav]

Hi levitated,

Your build looks very nice to me

I’m thinking about building efoil myself.
How did you choose foil profile on airfoils.com?
How did you come to the foil shape?
How did you make a mast? What was milled? What shape did you choose. How many layers of carbon weave and which type (g/m2)
How did you make mast foot?

I’d like to build something very similar to yours. I’m 82 kg weight.

[levitater]

I measured a levitaz foil and tried to take the measurements for my foil.
The mast has a wooden core that was milled. I took the profile from airfoiltools.com (sorry but I don’t remember which one I took) and made a template of it for the melling process.
Afterwards I laminated 2 layers of 100g/m^2 köper fiberglass and 2 layers of 160g/m^2 köper carbon. It is all layed by hand without vakuum.
The wings have 3 layers fiberglass.
For the connection between wing-fuselage-mast and also the mast foot, I 3d printed molds which I casted with epoxy and fiberglass.

[levitater]

My complete foil weighs around 2,5 kg.
Has anybody a foil-weight to compare?
(It is my first foil and I don’t know how heavy normal foils are)
Mast length is 70cm.

[Mislav]

If it is with wings and fuselage it is very light. Compared to Gong full carbon which is about 3,5 kg it is significantly lighter

[Alexandre]

5,3kg for my takuma …

[Vicdes2]

Weight wise, it seems pretty light but it will all come down to its ability to withstand forces created on an efoil. How thick is the profile?

[levitater]

Mast 15mm, front wing 12mm, fuselage 20mm and backwing 10mm maximal thickness.
Not assembled, I put the mast, the fuselage and the frotwing on two chairs and was able to stand on them. The only parts I am a little concerned about are the connection between fuselage and mast and the mast foot. But I will give it a try with my kite for a first test. I think if this foil is able to withstand a good downwind session, it will be strong enough to handle the forces of an efoil.

[Dynamik]

Hi, 2x 6s11p batteries (i.e. 12s22p) is quite a lot, but undoubtedly the right solution. It will extend the life of the cells. I too plan on 13s and 16 to 20p, yet some here are questioning that.

However, you initially chose the APS 80100 motor and your own DIY wing, but now use the weaker APS 63100 motor and the RL commercial wing. why did you make that decision? And what type of propeller did you use? The answer will certainly be of interest to a lot of people who are just deciding on the engine type and a custom or commercial wing.

[e-Jetter]

I believe he meant 2 x 6s11p in series, so 12s11p.

[Dynamik]

You’re right, I’m a little confused.

[levitater]

I read a lot in this forum and came to the conclusion, that the 63100 tends to be more efficient.
Same at the foil. My DIY wing seems to be ok for kiting, but when it it comes to power consumption, I don’t think that I have a chance against commercial wings. For me it seems like the power consumption is the most important issue at the whole projekt.

Volker's second build (shorty)

for those with the “new” 63100

This is the prop I use. Works perfectly for me.

[Captainjack20017]

Heya!
I have been totally hooked to efoiling lately but couldn’t find anything that was cheap enough (I have about 1000 euro’s and no work) so I was wondering how much time and money this took you in total? Also, does it require a lot of knowledge of electronics? (I have a few people that have knowledge of electronics but I don’t see them very often)

Kind regards,
Captain jack