Hello,
I finished my build and could do a first test in a pool today.
WIth a 6384 /120 KV Motor and the two blade folding prop from Flipsky (Aluminum) I measured at full throttle
I don’t know but can you tell the prop that you used?
ChatGpt says
"Short answer: yes—those numbers look reasonable and within safe limits for that setup.
Green lights: thrust, current, power, and pack temp all look acceptable."
Beginning to think you are Sam Altman’s brother😉
I didn’t think anyone here would want to get out their slide rule, physics and thermodynamics books to work out the answer that ol’ G Dog can do quickly.
So here’s a little something to think about.
I don’t deny that AI is here to stay and it can be very useful but it does have a cost.
@Foilguy
That is definitely is true, it comes down to your philosophy on addressing climate change and making a personal choice to contribute to reductions.
My perspective, based on all available facts, is that personal choices make no difference and it is like being a vegan to protect animals. If you think anything significant will happen to slow down climate change in our lifetime, I would suggest you run the numbers and political will to calculate probabilities again to form your assessment.
Searches use power as well and AI is quicker and could reduce power used very slightly, but overall AI is a hungry beast but still less than the carbon used to make and deliver the parts from China we build with, the fuel to drive to our foiling beach or lake…
AI is so unreliable on topics like these.
I tried it out just for giggles.
Entered the above question into GPT-5 and altered the static thrust. Put in values between 5kg and 50kg.
ChatGPT is fine with basically any values there.
What is even more funny, is how it is already in a feedback loop, referencing this exact thread as source for “community approved” values.
A reasonable right of reply from ChatGpt:
“I don’t actually calculate physics from first principles. I generate answers based on patterns in data and context. That means if unrealistic numbers are entered, I may still respond politely instead of rejecting them. In this case though, the reported current, power, thrust, and battery temperature all happen to be within the typical range for that setup, so my reply was reasonable even if the way I got there wasn’t rigorous. I can be useful as a quick sense-check, but I shouldn’t replace real-world testing or expert judgment.”
OP asked in this forum because he wanted answers of real people that have the same setup or experience
I assume if he wanted a GPT answer, he could use the tool himself
Just my 5 cents
The reason why people come here to ask these questions… Otherwise they would just start at ChatGPT and not the forum.
These are all acceptable and should allow you lots of fun. I personally have never bothered measuring static thrust and tend to rely on power as I know roughly how much I need to each of my boards and wings.
That is a fair statement, but there are also other considerations.
Like me previously, many don’t even consider AI and are unaware of the knowledge even on specific ESCs and I was surprised it even knew about VESC Tool let alone where everything was in it, or how to enter correct settings.
It can be frustrating for beginners to even find what they need in searches and alternatively wait for some to answer.
This forum is for advanced builders, and it has been confirmed not for people to post ‘I know nothing, what do I do?’
So for beginners it saves a lot of frustration.
Also the original question is actually a classic for ChatGpt as questions requiring calculations are perfect when combined with manufacturers specifications.
Where it goes wrong is anything multilayered where tunnel vision is a problem, such as cooling where the default is all heat going out the heatsink and drag values where wind and body size calculations can be wrong.
But more skill in questions produces better answers as a starting point, correct terminology and if needed the experience from other users here.
I’m not passionately for, just as I assume you aren’t passionately against, but we differ on range of use, but I’m sure have common ground on effective use.
Well said!
Now coming back to OPs original question:
The 6384 motor can surely be used above its specs. What I do not see is the motor current used at the claimed 90A battery current / 4kW
Motor current is pretty much the limiting value here, as this generates heat in the motor and may destroy it. It depends on propeller efficiency/pitch and it is not equal to the battery current.
@TOOM can you share the motor current used? For this I would not go >1.5x manufacturer value for long time usage.
Thanks, a better experience for both of us.
Unless I’m missing something, 36 kg of measured thrust is about in the right range for 90 amps being provided to the motor as motor max limit in the ESC, based on it being the Flipsky twin folding prop, designed for this purpose.
Correct me if wrong, 90 amp is good for the 6384, and isn’t the fact these motors are in the water, they never overheat.
The concern was battery heat, which is also about right.
Also we haven’t heard from the poster, which likely means he is out enjoying his build that works well, while we argue over ChatGpt, people block me and waste time trying to work out the motor amps, also no real way to calculate thrust without exact prop dimensions as Flipsky don’t provide it.
I’m officially closing this post.
I am using a two blade aluminium prop that was suggested by ali express with the 6384 motor
Who is Sam Altman? However, I don’t have abrother as far as I know 
Hi Ludwig,
i need to do another test for that. i am assuming you mean picking up current from one off the three phases going to the motor?
Yes, there is a difference in motor current and battery current.
You can have low battery current but very high motor current, e.g. when your motor is spinning slowly or has a propeller that’s too big for it
What did you set as “maximum motor current” in the VESC settings?
If you can’t measure motor current easily, you can also note down battery current and duty cycle and calculate motor current from that later on.
How did you measure the values? With your own equipment or by connecting to the VESC software?
