Fresh build from Slovenia

[lukmo]

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: I have connections in jet surf company that sells carbon casted props. I will go to the company with the motor and we will me one that fits.

For the board I got myself a sponsor (flikkaboards) 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 boat hatch on top of the board and inside to have 2 waterproof boxes

For the battery I will use 18650 cells. I think config eill 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)

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!

[lukmo]

Update:

My plan is to have kinda removable mast, but I really dont want do deal with water leaks, so I imagined I could have 2 seperate hatchers in board. One small 10x10cm just for cables and watercooling tubes, and one big for electronics. So the idea is to have “foldable mast from board”. When you need to transport the board you just unscrew 2 screws that hold mastplate and mast and just pull it out a little (max 10cm) and have the mast transported in parallel with the board.

Advantages: easy transport, no leaks because there is no seperating the mast from board (silicone is on both sites of cables)
Disadvantages: hard to find place to store 3x8AWG 10cm and water tube.

Let me know if anyone has any expirience with this kind of idea…

BR

[lukmo]

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

[sat_be]

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.

[lukmo]

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

Thanks BR

[lukmo]

How do there turn out? Do they send the spark to esc?

[sat_be]

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.

[lukmo]

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

[sat_be]

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.

[lukmo]

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

[sat_be]

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.

[Foliengriller]

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.

[lukmo]

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

Br

[jkoljo]

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

[Foliengriller]

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.