thank you, gentlemen, much appreciated.👍

Thank you I will check them out.👍

Agreed with Float a Boat. Great service and good people.

Best place is Float a Boat in Melbourne they have a good range of Rabosch brass props for scale boats.👍

Can anybody tell me the best place to get propellers from in Australia.
Thank You in Advance.😆

For a single prop I would go with a counterclockwise prop. Most motors are manufactured to turn counterclockwise (for efficiency) anyway. Check the data sheet for the motor you want. Here is an example of a common motor: https://datasheetspdf.com/pdf-file/1401824/MABUCHI/RS-380PH/1

Also note that most motor spec sheets show the direction as looking at the shaft end of the motor. This works out well as boat propeller directions are typically viewed from looking at the transom.

Lew

What I was actually asking was that when matching an electric boat motor to a propellor, what direction do I need for a motor that turns clockwise for forward motion.....a left hand or right hand propellor?

I think this subject goes a little "deeper". If my old memory serves me correct I believe the theory is that a boat's transom actually moves left or right because of the propeller's depth in the water. Water near the surface has less pressure, and that pressure increases the deeper the propeller gets.

The bottom line is that if a propeller turns counterclockwise there is less sideways pressure near the surface and the opposite side of the propeller (the bottom) has more sideways pressure forcing the stern of the boat's transom to go left (port). For clockwise rotation the opposite is true.

So using a counterclockwise prop will cause the stern to move to the left and this is handy when docking a boat to the port or left side of the boat. By steering slightly to the left while going forward slowly the whole boat will actually slide sideways slightly left. This will make it easier to dock to the port side of the boat. If you want to make it easier to dock to the right side you would use a clockwise turning propeller. (Most use the left, port, side).

As for dual props turning in opposite directions the sideways forces are equalized by each propeller. However if the left prop turns counterclockwise and the right prop turns clockwise there is more afterward thrust, again due to the deeper pressure.

One thing to watch for when using brushed motors is most of them are more efficient in one direction than the other. This is due to the brushes being offset inside the motor. In my experience it seems the RPM is also greater due to this fact. So using two identical motors one on each prop, may cause one prop to turn slightly faster than the other.

Lew

Thanks Len that's the answer I wanted....👍

However...which side gets CW or CCW rotation? Is there conventional wisdom to, say, enhance steering? Or stern behaviour? I hav a Kort nozzle on my RTR tug, single shaft. But my interest is in what configuration to use on my twin-screw Springer tug.

Propellers are either right or left hand. Looking at the face of the propeller, if when it turns right it pushes water aft, or in actuality pulls the shaft trough the water in that direction. On dual shaft boats a common setup is when the props are spinning outboard, the vessel is being propelled forward. Then at a less efficient rate when turning the inverse the vessel will propel in the aft direction.

Cheers!

What does one do to lessen prop walk in the case of 2 shafts?

By the direction of the motor