Model Boat Mayhem - Forum

Please login or register.

Login with username, password and session length.
Pages: [1]   Go Down

Author Topic: Should I consider Torque vs KV  (Read 573 times)

sigfortunata

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 58
  • Model Boat Mayhem is Great!
  • Location: Staffordshire
Should I consider Torque vs KV
« on: September 24, 2017, 10:43:34 PM »

Just general question really.


Through necessity I have a Turnigy D2826/6 motor rated at 2200kv  in an aerokits Sea Hornet. It was a temporary fit not planned. 


I run it on a 3S lipo.  The boat is quick but the motor gets really hot ( not smoking hot) just too hot to comfortably hold but I would expect this as its not really fit for purpose.
 
So I want to fit a more suitable motor. Originally it had a 3536  ???turns  1000kv on 14.8v but I've came to realise  that was TOO big. (I hit a buoy flat out, the boat took off, flipped and promptly sank which is what ruined the motor necessitating the temporary fit)


So I'm looking at a 3530/14  1100kv which will clearly develop more torque and enough speed but will it run cooler?   


I don't know, suggestions, view all welcome


 
Logged

chas

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 366
  • now in los montesinos Spain.
Re: Should I consider Torque vs KV
« Reply #1 on: September 24, 2017, 10:59:09 PM »

Could you try a slightly smaller propeller? Less load = less amps= less heat.

Logged

sigfortunata

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 58
  • Model Boat Mayhem is Great!
  • Location: Staffordshire
Re: Should I consider Torque vs KV
« Reply #2 on: September 24, 2017, 11:05:27 PM »

Hi Chas


I have dropped the prop size from 35 to 30mm, forgot to mention I did that as a matter of course, sorry. 


The fitted motor is really just not suitable, it was intended for an airboat project and I wanted high KV, I need to change it out rather then compromise to make it work, smaller prop, dropping a battery cell etc
Logged

canabus

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 753
  • Boats a hole in the water you pour money into!!!
  • Location: Tasmania,Australia
Re: Should I consider Torque vs KV
« Reply #3 on: September 25, 2017, 05:04:15 AM »

Hi sigfortunata
I am running a B28-57-15L 1900kv on 3S with a 45Amp car ESC and a 2 blade 32mm 1.4 pitch prop.
Also my mate is running the same setup, but with a B28-57-17L 1700kv.

Both are in Aerokits Sea Hornets.
My 1900kv has an air scoop on the engine hatch with an outlet under the rear dash.
No ware cooling!!!

Canabus
Logged

unbuiltnautilus

  • Portsmouth Model Boat Display Team
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 2,986
  • Location: Portsmouth, England, third rock from the Sun....
Re: Should I consider Torque vs KV
« Reply #4 on: September 25, 2017, 06:11:42 AM »

Try 1000kv at 7.4v, but the slightly bigger prop. I think torque is your friend in the thicker environment of water rather than air.
Logged
Listen politely, nod approvingly, then do what you want, works for me!

sigfortunata

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 58
  • Model Boat Mayhem is Great!
  • Location: Staffordshire
Re: Should I consider Torque vs KV
« Reply #5 on: September 25, 2017, 06:41:50 AM »

Thank you gentlemen  :-))
Logged
Pages: [1]   Go Up