New waist belt foil assist build from Queensland

The more you know about something, the better ChatGpt is. But even as a beginner it was great for me. Lots of chats about how VESCs work.

I think the problem you had was the exact terminology, which when I started meant even searching online to solve problems was an issue.

So you knew what you wanted, but ChatGpt didn’t.

Well done for a nice build, my first two failed. I’m up at Rainbow Beach and the isolation was a challenge.

Thanks guys.
Actually after fixing the initial problem (motor phase wire solder joint) the system works flawlessly. So i am a little hesitent to replace the little 80A ESC.

Ive just ordered a HOTA D6 Pro charger which can charge 2 6S packs in 1/2 hour or so… so i am committing to 2x 6S packs. I’m just not sure if I should add BMSs to my new packs

A friends 13 year old son had a crack and got up after a few attempts. And had few others interested so suspect i will build more.

@ZedMan oh you are faily close… i am on the Sunny Coast (Bokarina). I would love to take it up to DI once i can ride waves (yet to try the surf).

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I am from 2. to 9.1.2026 with my backpack and tow setup in noosa heads. If you are close and want to compare your setup let me know. Regards Robert

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Tim you don’t need BMS if you are charging with the style of charger you are using. Had good success with the Daly BMS if you want to use a simpler charger.

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Thanks. I had read that some time ago too.
How often do you need to do a balance charge vs a regular charge?

I’d do it every charge, just a matter of plugging both cables in so worth a few seconds

So after using this I have the following updates…

It works really well, however the Molicel P42A cells I am using are not up to the task as I am running 12S2P (2 x 6S2P packs in series). The cells get very very hot and voltage sag is evident after about 6 minutes motoring resulting in having to stop around 10minutes. To be fair I am new to foiling and end up using a lot of power a lot of the time… rather than what this system is designed for (assist only). Ie I am not doing a lot of foiling/surfing. Also worth mentioning is that i am likely killing the batteries as i am riding an Axis ARTv2 999 foil… which requires a lot of speed. So i will try another session on a slower and bigger wing. I should probably rebuild using 3P but I find the 2P setup manageable weight-wise and think more might be uncomfortable.

So I will order some RS50 cells and use those. And will repurpose the P42A cells for a 12S4P setup (I will post details - will be an on or in board setup).

Also I have ditched the original aluminium Flipsky 2-blade folding prop as it is too noisy and I have been using a 3D printed 3-blade prop. This works incredibly well - it is much quieter and has more torque and less battery use.
I got the model from here: Propeller for E-foil / ASSIST - Share Project - PCBWay big thanks to @Bzhwindtalker !!
I printed the hub with an FDM printer (Bambulabs P1S) using PETG-CF (6 layers and 50% infill).
And the most amazing discovery is the Siraya Tech Blu resins - I have used the Black Lava - this is incredible - it has a very high tensile strength and tensile modulus - I am sure on par with the Formlabs printers/resins that the FD team use. So I have printed the props in this resin on my very old AnyCubic Photon printer. I haven’t even sanded them - just washed in IPA (5 mins), dried with a paper towel and post cured for 15 mins (in an Elegoo Cure station).
I have printed spares… but not needed them (to be fair I have only used it 3 times).

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My original BDUAV 6384 motor died… I had mistakenly crushed the wires coming off the coils against the housing when reassembling and this caused rapid oxidation and the wires broke too short to salvage.

So I have replaced it with a new waterproof Saite 6484 motor… this, it turns out is much better. I can cruise on my high aspect foil (Axis ART v2 999) at 50-55% throttle - where as previously I was cruising around 60-65+% which was causing my batteries to get very hot.
Now I find the batteries only get warm (quite warm) and I don’t experience the dramatic voltage sag I was getting (well, not nearly as badly).
So it was a very positive change (although at 4 times the price you would probably expect that).