Bowthruster propeller thrust and blades

[haydude]

I have a Vetus bowthruster with one standard three blades propeller which is fine in a light breeze, but struggles to swing the bow over 12kts cross wind.

I was told that fitting a propeller with more blades would increase thrust. Is that correct? I thought that pitch and size (the latter cannot change due to the tunnel size) did matter.

 

[pvb]

I have a Vetus bowthruster with one standard three blades propeller which is fine in a light breeze, but struggles to swing the bow over 12kts cross wind.

I was told that fitting a propeller with more blades would increase thrust. Is that correct? I thought that pitch and size (the latter cannot change due to the tunnel size) did matter.

Your bowthruster will have been supplied with the optimum propeller for its characteristics. If it doesn't give enough thrust to counter your boat's windage, it looks like your thruster was under-specified.

 

[Bloater]

Vetus have an upgrade which is a replacement prop with 5 or 6 blades on it. I've just bought a 75Kg rated thruster but with the new blades (came supplied) it is rated at 80kg force.

You probably can change the blades but you may only get a 5-10% performance increase.

 

[Huttoft]

Hello.
My Vetus thruster was originally supplied with a three bladed prop. I have changed it for a five bladed version because I understand that it is Vetus's policy to renew/replace three bladed with five.
I may be wrong but if you contact Vetus no doubt they will put you straight.