Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Other Technical Questions... => Topic started by: Bugsy on November 10, 2010, 08:47:51 am

Title: A quick question on twin rudders
Post by: Bugsy on November 10, 2010, 08:47:51 am

I'm scratch-building a one metre model of a French customs launch with a 'V' hull very similar to an MTB boat.

Should the rudders be fitted vertical to the centre-line or 90 degrees to the two sides of the shallow 'V'.

Thanks.

Title: Re: A quick question on twin rudders
Post by: TomTheKraut on November 10, 2010, 12:11:10 pm

Salut Bugsy,
I would opt for "vertical to the waterline" (not "vertical to the bottom plank") in order to avoid funny up-/down-forces to the bow when initiating a turn.

If you lay rudder to a vertical rudder face, only lateral forces will apply to the rudder blade - thus creating only a lateral influence to the hull.
If you lay rudder to a sloped rudder face, lateral as well as vertical forces will apply to the rudder blade. The lateral influences to the hull will be (under otherwise equal conditions) less than with vertical rudder blades.

Title: Re: A quick question on twin rudders
Post by: Bugsy on November 10, 2010, 01:04:36 pm

Thanks Tom for a very concise answer. :-))