Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Other Technical Questions... => Topic started by: apennicardwood1 on August 23, 2012, 07:08:57 am

Title: Rudder Position
Post by: apennicardwood1 on August 23, 2012, 07:08:57 am

Hi All
I am looking at moving the rudder on my fast electric boat, at the moment it is off to one side of the hull and i was going to move it in line with the prop.
What i would like to know is why the rudder is put off to one side and if i move it will it help?
Thanks for any advice you can give.

Title: Re: Rudder Position
Post by: Martin (Admin) on August 23, 2012, 11:07:04 am

 
The wake coming from any prop is actually corkscrewed, causing the boat to try and twist in the opposite direction, the rudder being
behind the prop on a 'fast electric' will exaggerate the effect increasing drag and reducing the boats turning ability. The rudder is therefore
offset, usually to the right to reduce this effect.

I think the idea is that there is so much water passing under a 'fast electric' that it doesn't really matter where the rudder actually is.

Title: Re: Rudder Position
Post by: apennicardwood1 on August 23, 2012, 12:09:08 pm

The rudder on my boat is set to the left of the prop and yes when it gets up and going it turns well, however i need a big space to get up to speed so at low speed i get almost no turn. To start with i don't think the rudder or servo was working as it powered away from me.
Would it be but then to put a twin rudder on to help at low speed?

Title: Re: Rudder Position
Post by: malcolmfrary on August 23, 2012, 08:59:01 pm

A second rudder might help at low speed, but then, you might never get the high speed. 
I think some of the preference for the left mounted rudder was for left turn racing.

Title: Re: Rudder Position
Post by: apennicardwood1 on August 23, 2012, 10:46:31 pm

ok thanks for the advice i will have more of a play with this boat to see what will work best.
Thanks again for the advice.