prop sizing

[kagallag]

I need a new prop, as cheap as poss, for 1GM10 (not sure about gear ratio), 25mm shaft for a 29ft boat. How do I know what size to use and any useful contacts ?

 

[Kilter]

No connection...satisfied customer! Try here

 

[kagallag]

looks useful, thanks

 

[roly_voya]

Start with what you already have and then allow for changes. IE if going up 10% in power go up 10% in blade area, if the revs are 10% low then decrease the pitch by 10%.

 

[bendyone]

I got mine from here, very good service.

web page

 

[KAL]

Try looking at www.castlemarine.co.uk They have a simple downloadable program called 'propcalc', into which you enter as many details of your boat as possible (LOA/LWL/Hull type/engine HP/gear ratio/displacement when cruising, etc. It will then tell you what size suits your boat best. Try www.coastalrides.co.uk for the prop.