Hi Steven,

Props are quite possibly the easiest thing to change on model boats. They also have a major impact on any boat's performance and battery life.

We should always remember that electric motors - brushed or brushless - really love to rev. Therefore if a prop causes a motor to run hot at all, things definitely point to the prop being too big and\ or course pitch putting the motor under undue strain.

Conversely, if a motor runs fast and cool; but with disappointing performance, we could well have a too small or fine pitch prop.

It's just a matter of experimenting. Alternatively, if you are in a club speak with owners of similar sized boats. You can simply copy what works well to gain from other's experience.

Happy sailing!

Dr. John. F. Leeds and Bradford. BBC. 😊😊😊

A Fairey deserves to have a brass or bronze prop! 😀

If it performed well on a 40mm I'd stick with that or maybe go up to 45mm if you have the clearance.

Hi Stephen
I'm with Colin brass props are far more efficient and resilient.
dave976

StephenT, I take it you were referring to plastic props, I only use brass or stainless steel and have never broke one in my modelling life. . Cheers Colin.

If you running a brushed motor go for a S45 or S50 two blade or if brushless definitely run X45 or X50