Third time lucky… No I am not hitting the limits… Here is the graph for the phase and battery currents:
Currents are all set to a max of 150A…
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Hey! Can you share the stl for the hexacopter?
Thanks
Does anyone know where to get a similar motor to these discussed here with a 50kV rating? i dont really want to get into re winding the stators as its very labour intensive. The way forward with all this is to increase voltage to 24s and half the current… half the current and heat is 4x less, just saying 
Good luck…it should be a “shocking” experience 
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Shocking experience indeed.
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Maybe you should change you nickname to “ electric eel”
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Well … if your battery/ESC box is manufactured by space grade company like SpaceX or Boeing made from titanium. I see nothing to be afraid of.
Do not forget to put two 12s ESC in series
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I don’t see what problem you’re solving by going to lethal voltages.
Heat in ESC is 4x less but ESC cooling works fine for most of us at 100kV (sure, you lower losses by some hundred watts there)
Heat in motor for the same torque is the same regardless of kV if only copper fill in winding remains the same for the compared windings.
Well thanks - considering you dont know me, or what i do for a living (electrician) im happy to advise that after 10 years working with lethal voltages everyday - im still alive and well - but thankyou for your concern
Have a look at EVs (cars), electric aircraft etc - you will see a common pattern of moving to higher voltages as the technology evolves. Under 100VDC is still not even considered low voltage these days - its called extra low voltage. Do not let fear hinder your progress towards better things!
How many ESCs have you fried? im guessing most of you would have blown a few by now? Not hard to do when your asking such large amounts of current from your system. Lower currents solve so many problems, not just heat. What your asking of your batteries, ESCs becomes much lighter work when the current is lower. The physical size of the wiring, internal component conductors, the duty cycle rating of contacts, switches, transistors in the ESCs etc all needs to be very large when dealing with high amperage - most RC stuff isnt all that great and all your components will last much longer if you can drop the current. But assuming you have a reliable system, reducing the current will allow an increase in performance, longer run times, higher max output, more torque from a given diameter motor (which is a limiting design factor) etc whilst keeping the same reliability.
Provided you have a sensibly designed system - the higher voltage is nothing to be scared of IMHO, but i guess my exposure to higher voltages everyday and understanding of what would be required to make it safe makes it easier for me to be comfortable with it…
i notice some here are running 16S batteries - thats a step in the right direction and is still extremely safe. However in order to still run an efficient prop - were going to need lower kv motors or the motor runs in overloaded condition. Theres a unique balance between all these things which some seem to have better dialed like FR - and some clearly have no idea what their doing…
I came here looking for information about good quality suitable motors (around 50kv) with good seal design to keep water and debris out, in order to build a reliable system to go with my high speed foils and perhaps even scale it up as a prototype to a foiling full size e-boat for carrying passengers
We have a dutch wordt for people who are scared for new things: Gewoontediertjes ( Animals who would like to keep doing what they know ).
But I like your approach! Now that all the usual 48V stuff in the industry got milked and used ( because it was all available because of the 4 times AGM batteries in series systems ) to their max, the big brands are starting to innovate and are looking into train / rail standards where 100V DC is a standard in some places.
100V is mainly a problem when it can run trough your body, just keep the ( + and - ) conductors close enough to always motivate a shorter path 
.
In small EV cases I think 100V is the next big thing / future!
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Reachertech do a 80Kv version of the 65161. Similar to the flipsky 65161. I run the Reachertech 80Kv on 14s and it could use a few more RPM. Trampa are doing a 100v VESC now, so i guess those might be a few options.
As an electrician, what would you consider to be a safe voltage if a fault was to occur in water?
Personally, i think is inappropriate and irresponsible to be promoting higher voltages to a DIY community that are NOT electricians.
We are working in our garages on our projects AND making mistakes with voltages which probably wont kill us. Could you say the same if we were working with 100v systems?
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Beside safety concerns and personal preference there are regulatory compliances and restrictions for marine applications. Even in cars there numerous safety and failsafe regulations and certifying higher voltage packs takes years of tests and QC. Even 14 or 16s exposes big danger if things go wrong. If you are not scared of high voltage means you never experienced it and if you did you probably wouldn’t be able to confirm from the other side. But again it doesn’t mean that it is impossible
my experience:
my first board (battery 12s on top, phase wires running on the side) , my leg came on the motor phase connectors “waterproof”, 50v is enough for me, i don’t want to test more…
before on 8s , i never felt anything
i am not really afraid of" high" voltage , i am just afraid of taking a shock and fall in the water, not exactly the same than when you are" prepared" to crash hard
I am an EE. I would like to hear what measures you think can be taken to make 100v and 50+amps DC (and much higher than that in the phase wires) safe for use in something that gets submerged and the user literally hugs their body to under water. Remember also, that people will be playing with their open compartments when wet.
The thing we are worried about is the arc potential. This does a good job of showing the dangers of arcing. Everything is particularly more dangerous when you add water directly to the combo:
People die when 110v AC systems are not properly grounded around docks and they jump in the water:
Finally, google Kentucky Fried Fingers if you want to see what happens to the fingers of amateurs while playing with ebike battery voltages higher than about 20s.
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No, that’s not the case. High kV motors and low kV are equal in torque capability. It’s the rest of the system that can set boundaries on this if not balanced. The field strength capability (torque) is measured in ampereturns and will be constant for a given stator.
This is good news ! IMHO The M8 Threaded shaft is much better than the other variants. It allows for easy adaptation of many more propeller options.
Some more detail on this area would be good as far as dimensions would be nice as well.
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100V is just not necessary because we fly with power between 800-1500W already, leading to currents of around 20A, so no need to increase voltage! in germany we even have a law, making it difficult to build watertoys with more than 50V
So if you dont think of setting speed records better aim for more efficiency on your setup instead of increasing voltage to get lower amps and temperature... In case you are not able to foil with 800W...try our new composite prop hyperblade.. available for 10 and 12mm shafts and fits 140-160mm ducts.. (we dont recommend using without as blades are very thin!)
