Hi, you seem very experienced but I will say this anyway since Edwin Cordero said 14S = more power. The important to remember is that this is electric motor not a 60cc engine. Torque in an electric motor is dependent on current, not on voltage. Voltage dictates motor speed and overall size. Increasing the voltage above normal parameters will effectively increase the torque but overload the motor. So, torque (the strength to turn a small or a big prop ) in sea water for electric motor is the same with 6s 8s etc.!!!! KV means revolutions per minute per volt. It is not an indication of torque. So a 1000KV motor means 1000 revs per volt. 12 volts means = 12,000 revs per minute. This is already an issue since a real boat propeller spins at the speed of 5500 RPM (Revolutions Per Minute), with 5900 RPM being among the highest possible RPM values for a boat propeller Anyway, here point is - increasing the volts is what increases the revs. So choosing a lower KV motor (same watts specification) is a good idea to start with. So if say, we are using a 1KV motor - 50 size prop and 6s - and say the current is 50amps You have watts = V x A = 25 volts x 50 amps = 1250 watts. Max Revs is 1000 per volt = Max is therefor 25000 Now there are two ways to increasing speed - and here is the important. If we increase the prop size only - Voltage is fixed and the motor will draw a higher current to drive the higher load and we have 25 volts x example 70 amps = 1750 watts. or a bigger prop: 25 volts x 100 = 2500 watts. Note that the current only increases which is why ESC speck is in amps and must not be exceeded. OR we could increase the voltage to add more speed. SEE HOW THIS WORKS OUT, 14S lipo is approx 50 Volts. So using the same 50mm prop we have 50 volts - THE CURRENT REMAINS THE SAME - WE HAVE THE SAME PROP 50 V x 50 Amps = 2500 Watts. This is in fact a much safer way of avoiding overheating and increasing speed. The speed comes out of more revs per volt 50 volts - 1000KV motor = 50,000 This is of course theory - since there are many elements at play here. A hull not designed for such high speeds, as is certainly the case for our RC Huntsman, will cause the prop to lose MORE grip AT SUCH HIGH REVS which is why 6s to 14 s is certainly not going to double the speed. The pop would be ventilating AND/or gravitating. In fact you would find that using a smaller pitch prop (I did not say smaller size) will make the boat go faster - since it would be easier for the prop to worm its way round the water and gain grip the water. Strictly speaking you can work the speed from the the pitch of the prop A prop with a pitch of 1cm and 50,000 revs means boat should travel 50,000 cm per minute - approx 18MPH. Anyway hope this helps anyone that reads it.
Nice. Remember, 14S = more power and also more weight and stress on the hull and not necessarily more too speed. It's going to be very heavy. Following your tests. Thanks.
That’s some very fine engineering you have done there.
Nice work👌
Thankyou sir, but nothing too difficult
Wowzers!! What a rocket ship!! 84kphr amazing. Huge power and still cool!! Yep lets prop up!!👍🏻🚀
🤣
Hi, you seem very experienced but I will say this anyway since Edwin Cordero said 14S = more power. The important to remember is that this is electric motor not a 60cc engine.
Torque in an electric motor is dependent on current, not on voltage. Voltage dictates motor speed and overall size. Increasing the voltage above normal parameters will effectively increase the torque but overload the motor.
So, torque (the strength to turn a small or a big prop ) in sea water for electric motor is the same with 6s 8s etc.!!!!
KV means revolutions per minute per volt. It is not an indication of torque.
So a 1000KV motor means 1000 revs per volt.
12 volts means = 12,000 revs per minute.
This is already an issue since a real boat propeller spins at the speed of 5500 RPM (Revolutions Per Minute), with 5900 RPM being among the highest possible RPM values for a boat propeller
Anyway, here point is - increasing the volts is what increases the revs.
So choosing a lower KV motor (same watts specification) is a good idea to start with.
So if say, we are using a 1KV motor - 50 size prop and 6s - and say the current is 50amps
You have watts = V x A = 25 volts x 50 amps = 1250 watts.
Max Revs is 1000 per volt = Max is therefor 25000
Now there are two ways to increasing speed - and here is the important.
If we increase the prop size only - Voltage is fixed and the motor will draw a higher current to drive the higher load and we have 25 volts x example 70 amps = 1750 watts.
or a bigger prop: 25 volts x 100 = 2500 watts.
Note that the current only increases which is why ESC speck is in amps and must not be exceeded.
OR we could increase the voltage to add more speed.
SEE HOW THIS WORKS OUT,
14S lipo is approx 50 Volts.
So using the same 50mm prop we have
50 volts - THE CURRENT REMAINS THE SAME - WE HAVE THE SAME PROP
50 V x 50 Amps = 2500 Watts.
This is in fact a much safer way of avoiding overheating and increasing speed.
The speed comes out of more revs per volt 50 volts - 1000KV motor = 50,000
This is of course theory - since there are many elements at play here.
A hull not designed for such high speeds, as is certainly the case for our RC Huntsman, will cause the prop to lose MORE grip AT SUCH HIGH REVS which is why 6s to 14 s is certainly not going to double the speed. The pop would be ventilating AND/or gravitating.
In fact you would find that using a smaller pitch prop (I did not say smaller size) will make
the boat go faster - since it would be easier for the prop to worm its way round the water and gain grip the water.
Strictly speaking you can work the speed from the the pitch of the prop
A prop with a pitch of 1cm and 50,000 revs means boat should travel 50,000 cm per minute - approx 18MPH.
Anyway hope this helps anyone that reads it.
Nice job mate 👍 👌
Amazing how stable she is even at that speed, and looks awesome on the water.
It looks even better in real life, i never want to bring it in lol
It's going very well , nice work mate. Very enjoyable to watch.
Nice. Remember, 14S = more power and also more weight and stress on the hull and not necessarily more too speed. It's going to be very heavy. Following your tests. Thanks.
What battery bank are you using. 2x(3+4 S) series(d) together?
1x 6s and 2x 4s, plenty of ways to go about it
47mph with a 5860 and 300A esc on 12S!?! 😆😆😆
Yep shes never going to be a rocket with that hull, what did you expect?
what kv motor?
84 mph or km ?
My australian accent didnt give it away lol