Fresh build from Slovenia

Hello builders!

In august this year i started my end school project e-foil. I bought the complete foil from RL boards @kiterr . Got it on friday. The quallity of the wings is insane. Everything is visible in carbon fibre, the mastplate already has holes for cables.

On wednesday I ordered hgl tech 65162 100kV version from firduo. (Cheaper than flipskys)
For the prop: Not made decision yet…

For the board I got myself a sponsor (flikka-boards) and for right now I am shaping in 3dshape design pro software. In october we will slowly start production of the board (cnc).
-board will be ~67l
(Will upload pics after I get home)
-plan is to have mostly waterproof costum made hatch using carbon fibre and inside seperate waterproof boxes for electronics

For the battery I will use 18650 cells. I think config will be 12s12p. I dont know what cells i am going to use yet. I will design case for batt (will try to do something like lift), and than have it wrapped up with carbon.

For esc I have flipsky fsesc 6 60V 200A.

For water cooling I will use pressure from the motor holder.

I am designing my own remote. The case will be simmilar to @Hiorth . Their code was never seen by me, so had to code new one, but optimized. The plan is:
-will be using 2 esp32s
-the communication will be by ESPNOW ( esps new protocol, highly optimized, no delay, long range, cant nearly compare to bte)
-tft display on top with vesc info

  • the code is almost done, I just have to add the hall sensor, and vesc Uart to the code.

Stay tuned for updates!


Hello guys, does anyone have any good plan for turning on and off the vesc without damaging it… (spark)
I was reading about contactors and some antispark modules, but I didnt really get find the best option. Wouldn’t the reley send spark to vesc when turned on?
(If not, the reley should be good option for safety switch too?) Some people here are saying they dont have a problem with cutting current at high power, some do ( there is a lot of people with fried vescs too)
What would you recommend for this situation? (I will be running 12s which is max for my vesc…)
Br thank you

You could use the kill switch function of vesc fw5.3, see here: Flipsky 75200 ESC wiring - #3 by SoEFoil
This would not entirely switch off the vesc but there is no risk to destroy it this way.

Thats not a problem, cause I will keep my batt out side the board when not using it.

Thanks BR

How do they turn off? Do they send the spark to esc? image

They work like a fuse, the cheap ones all trip at around 60A regardless off the rating. The Spark is a problem when switching on (charging the VESC caps). If you use one of these, use AS connectors like AS150 or XT90AS for the battery and close the fuse switch BEFORE you connect the battery.


So what about normal fuse with xt90 connectors? (just plug and hope for no sparks?)

Works fine, see here: How to choose a fuse to protect the battery - #2 by sat_be
200A midiOtO works fine for over 2 years.

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Thank you so much for help! So just normal fuse and xt90 plug and play

XT90AS are fine if your current isn’t too high. For battery currents over 100A for more tha a few seconds, I would suggest to use AS150.

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I have until now build 3 boards and am underway with a 4th this way:
Small, non watertight box for the cable & watercooling connections and a watertight box for ESC and batteries. I do not use a separate waterproof box for the electronics - I think the waterproofing of the ESC is good enough for the occasional spray. Receiver and METR are coated with conformal coating (I use plastik 70 from Kontakt Chemie), batteries are packed in a case which is protected against water spray.
In the latest build I am building a wooden box with a small, wet compartment and a larger dry one for the batteries & electronics. both are under the same hatch; locking is done in the wet part so I do not have to rely on the seals in the latches.

One board I have build according to your idea above with ~8cm extra cable. This is pushed into the mast when assembled - it works for the occasional disassembly, but I do not think it will survive daily use for a long time.

And as you see XT90AS work fine for me in all builds - I typically use 60-90A during start (120kg all up weight) and 20-30A when cruising depending on speed (I usually go between 25 to 30km/h; never more than 35km/h) - so the 70A the XT90 is rated for is definitely enough for me.

So this boat hatch you use is not watertight?
I was looking to buy the simmilar one…?


I have tested 4 different hatches, and finally found the RWO 100mm inspection hatch. It has a proper seal, and doesn’t leak.

Yes, it is watertight - I just used it, because I had it lying around… but as the cables are coming in through an open hole from the bottom, there ist water inside.

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I will probably just have the seal between mast plate and board, so it will simplyer and still be removable. Any suggestions about what silicone glue or material should I use to make a solid seal?

BR Luka

Have you tested the RWO 150 or 200 mm versions ? If they are waterproof, they offer a much more comfortable opening…

Nope, haven’t tested those unfortunately.

Just a little update for anyone interested in my build:

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Nice battery box!

Arduino. - This is what my dad made to turn on the main relais.

It does also monitor pre-charging and temperature of the VESC (cooling pump on/off)

Basically when the Arduino is turned on by using a magnet on the reed switch (not shown in the picture), the Arduino will turn on relay 1, for pre-charging the VESC.

When pre-charge is done (monitored by the Arduino), it will turn on the 2nd relais what will power the big main relais.

The Arduino is also monitoring the temperature of the VESC. When the temperature gets to high (I think that it is set to 30c) it will turn relais 3 on and start the pump.

The little screen is only to show some debug info.

Communications from VESC <> Arduino is by TX/RX from the VESC’s comm port.

He is now working on a FET version to replace the 3 relais, and instead of using the comm port he is trying to use the CAN port.


Woaw, great job with those arduino and releys!
Well my idea is to have just normal click switch (waterproof) to have it in my electric box to turn the main reley on. I am not planning to use pump, just a water pressure since my mast clamp for rl boards is designed in that way to put as much water as can thru mast. My reley is monostable and it is turned on by sending unique 12V pwm (1 impulse high, other low). It is designed to work up to 60V 200A.

On monday my VX3 flipsky chould arrive and that is the remote I will use!

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