Model Boat Mayhem - Forum

Please login or register.

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

Author Topic: 3 or 4 bladed prop.  (Read 1584 times)

Popeye

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 285
  • I see no ships!
  • Location: Upminster, Essex, England
3 or 4 bladed prop.
« on: March 25, 2012, 11:15:59 PM »

Given the same diameter, which prop is better suited to an ungeared '540' low drain motor where torque is more important than speed?

It's required for  a deep drafted 'bath tub' and bluff bowed general purpose hull.

Thanks ya'll.
Logged
Confucius he say, 'if all else fails.......reach for the  Red Top-Stop'.

Tug-Kenny

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 7,717
  • Location: Newport. S Wales
Re: 3 or 4 bladed prop.
« Reply #1 on: March 26, 2012, 08:42:18 PM »


I would use a four bladed Propeller where torque is concerned. This becomes more powerful than a three bladed one, on slower revolutions.

ken

Logged
Despite the high cost of living   .......... It remains popular

Shipmate60

  • Global Moderator
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 5,238
  • You bark - I will bite!!!
  • Location: Fareham
Re: 3 or 4 bladed prop.
« Reply #2 on: March 26, 2012, 09:10:22 PM »

What is the performance criteria of the motor.
Most 540 derived motors don't supply much torque and need revs to provide power/speed.
Fot torque consider either a larger diameter motor or multi-pole motors.
540's only have 3 quite small windings.
540's are usually more suited to 2 blade racing type props which allow for higher revs.
It is fairly easy to check if the motor is over propped, it will get hot quite quickly and will have a large current draw.
You havent stated what diameter prop you are thinking of using with this motor.

Bob
Logged
Officially a GOG.

malcolmfrary

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 5,501
  • Location: Blackpool, Lancs, UK
Re: 3 or 4 bladed prop.
« Reply #3 on: March 27, 2012, 09:51:37 AM »

4 sounds good, but a 545 rather than a 540.  The extra couple of poles makes a big difference.  A lot depends on the size of the blades and the size and performance expected from the hull.
Logged
"With the right tool, you can break anything" - Garfield

essex2visuvesi

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 6,146
  • Location: Finland, England, Finland!
Re: 3 or 4 bladed prop.
« Reply #4 on: March 27, 2012, 10:44:02 AM »

If you want a slow running torquey motor in a 540 size can then this is the one
http://www.fusionhobbies.com/Carson-Poison-Truck-Motor-p/c906023.htm

I have one in my King Hauler truck and its a real improvement of the the stock 540.  Really improves the pulling power and also run times are inreased by about 10-15%
Logged
One By One The Penguins Steal My Sanity
Proud member of the OAM  (Order of the Armchair Modeller)
Junior member of the OGG  (Order of the Grumpy Git)

John W E

  • I see no ships !!
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 8,513
  • Location: South shields
Re: 3 or 4 bladed prop.
« Reply #5 on: March 27, 2012, 01:46:26 PM »



Hi have a look at the motors from Action go for the 555 motor
Have one in the MC ARCHER TUG driving a 4 blade 50mm prop on 7.2 volts :-))


http://www.modelboatmayhem.co.uk/forum/index.php?topic=27894.0



http://www.action-electronics.co.uk/stuff1.php

aye
john

Logged
Pages: [1]   Go Up