It looks like the drag coefficient isn’t that bad than i thought
Wow, what a coincidence that they decided to present an official number in literature
Would this be empty or with a riffle inside?
Okay folks, lest you think we’re not going to take this seriously here, let’s get back to the most important issue:
How can I stiffen this flabby piece of plastic?
Here we need to pay attention to the following:
- the stiffener should not add much weight to the complete efoil
- it must be able to absorb the forces from the weight of the surfer
- there must be a solid possibility for the mast plate to be screwed on, in order to transfer the force over a wide area to the bottom of the case and to the sides
- the case lid should of course still be able to be folded open
To accomplish all this, we have lasered and beveled an 3mm aluminum plate. Two more U-profiles are screwed onto this aluminum plate via Item aluminium profiles, on which the lid rests.
The mast plate is screwed by closed blind rivet nuts. I love these sexy waterproof rivet nuts! I use these now since my last 3 Efoils. It is the fastest and cheapest way to attach the mast plate in my opinion. You get very sturdy M8 stainless steel female threads. The pull-out force is given with 7840 N per rivet nut!
To pull in the rivet nuts, I bought an attachment for cordless drill for about 60€. It works so nice!
To adjust the height of vertical aluminum profiles exactly, we have printed stylish spacers. The correct height is of course crucial, because otherwise the lid no longer closes properly and the sealing cord is no longer properly pressed in.
Stay tuned
Here is a small update on the motor part: Flipsky 65161 120kV mounted with a POM plate and 3d printed parts. I used the same technique on my last build which worked really well.
The advantage here is:
- No nasty tensile stress on 3D printed components
- POM absorbs vibrations
- additional vibration damping can be achieved by placing sponge rubber between the two clamps --> THAT’S THE SECRET TO BUILDING A NEARLY SILENT DRIVE
- the screws to hold in place the cover part are not in the flow
- for me this is the first clamp design where nothing has ever broken again
- the idea came from @Peter
Pom is not necessary.
I have a similar design all parts printed. No need for screws to fix the cap, just click and go.
I am still working on my design, but I was planning to use a similar mounting method, and a cooling pass-thru in the center like this. It also helps with printing the nose cone, as it removes the centermost section that is a bit challenging for the FDM process.
That’s truly german over-engineering Love the design
What mast are you using in the above?
I’m using Rene’s RL Mast and also the complete RL eFoil Wing Kit (old Version). Just type “RL Mast” or “RL efoil” in the search bar and you will find some Posts about it
Hey guys,
our “Weapon of mass consumption” is entering the hot phase. A passive cooled HGLtech Hi 75/200 Vesc, mounted in a waterproof aluminium box will do the scutwork. It comes with 10AWG motorcables and 3 x XT60 plugs battery-sided. I cutted those (yay! free plugs) and soldered the 3 x 12AWG to a 8AWG cable. I also cutted the RJ45-plugs from an old networkcable and used it to extend the PPM+UART port of the Vesc to a second waterproof plasicbox which will be placed in the upper front of rifle case.
Metr-modul for wireless configuration+logging and Maytec Rx for PPM input
the electronics-box mounted on the stiffener-plate directly in front of the rivet nuts
So people, now it’s getting serious. We have actually landed far below 2000€.
For all those who want to build an Efoil now should use these components (as of January 2021).
Quiet motor, high quality battery pack (waterproof), passively cooled VESC (waterproof). High quality carbon Foil.
It took us less than one day (23h) to build everything!
BOM | |||
---|---|---|---|
shipping | |||
Flipsky 65161 120KV | banggood.com | 269,00 € | 8,00 € |
VESC HI200 75V 200A | hgltech.com (coupon HGLTECH20) | 161,00 € | 10,00 € |
RL Foil Set (Shark) | rlboards.com | 420,00 € | 15,00 € |
Battery 16S9P 30Q | nkon.nl | 460,00 € | 10,00 € |
Maytech Eskate remote | aliexpress.com (MTSKR2005WF) | 80,00 € | 20,00 € |
Max case 004 | max-koffer.de | 24,00 € | 5,00 € |
Nuprol X-Large Hard Case | kotte-zeller.de | 120,00 € | 12,00 € |
stiffer plate | Local Laser shop | 53,00 € | 0,00 € |
Item profile 30x30 | ebay.de | 20,00 € | 6,00 € |
aluminium case 172 x 121 x 54.9 | voelkner.de | 16,00 € | 5,00 € |
stuff | AS150 connectors, 8 AWG cables, screws, SikaFlex | 50,00 € | 0,00 € |
1.673,00 € | 91,00 € | ||
1.764,00 € | |||
working hours | |||
[h] | |||
propulsion unit | motor mount, cut POM piece, assembly of foil | 5 | |
battery | spot welding, soldering, prepare waterproof hard case | 7 | |
board assembly | screw stiffer plate to board, seal screw holes, install rivet nuts | 6 | |
VESC box | soldering, install cable glands, programming | 4 | |
remote | waterproofing remote with Epoxy | 1 | |
23 hours |
Nice BOM ! When do you think will be the first tests ?
One can find this item with 1 or 3 m extension antenna for 95usd (February 2021 Chinese New Year sale):
Thanks for the link. Well it’s winter in Germany…
Haha @SoEFoil, glad you asked for the first test;)
We will release the result soon…feel free to vote
Current results:
Nooo! Why did you go for the RL Shark foil…? you will not be able to push that case to 25kmh+ for lift-off.
Go for the superb E-foil dedicated foils where you have lift-off at 15kmh and you stand a chance…
I am sure, he will lift off :mortar_board:
It’s not the Shark, it’s the RL efoil Wing with around 1200cm²
Saw now in the video it’s the 2018 RL with 800mm width and ca 1100cm2. It’s my favorite allround wing sofar after testing 7 different. You will be successful! The Bom is balanced and good.
With a proper wing and 5kw to start with you can strap it to a toaster and still fly.
Go Germany!