Push me pull you rudders. Look good but you go absolutely nowhere.😃

I can only assume they are talking about something like this, and not conventional rudders.

Martin555.

Hi Guys,
I have built quite a few twin rudder boats/ships in my time and have always set them parallel to each other and have not had any problems.

I have just looked at my Southampton Tug and there seems to be a bit of loos play in them, by wiggling them i can get them parallel.

So i think the manufactures of these Tugs have just come up with a standard that is good enough.

Just to through you into total confusion i have even heard of some Tugs having independent rudder control as well as props, What advantages this has i am not sure.

Martin555.

Wow, some answers!
In my opinion there is not relationship between car steering and rudders.
i would expect the rudders to be parallel in all positions. eg straight ahead , rudder both straight.

Hi
Not sure re the car turning wheels point. I am not aware that the inner wheel turns less than the outer on a car. Certainly the outside wheel will rotate faster which is the reason a differential is fitted to the driven set or sets. There is such a thing as wheel camber or toe in or out. If the turning wheels turned at a different rate, this would cause seriou type scrub.

Regards
Kevin

I googled boat ship dual rudder alignment.
Got:- The importance of tuning your Rudders from power and motor yacht.com(no spaces)
As per my first query the article mentions toe in and toe out, plus Ackerman steering, now mainly obsolete and replaced by a computer.
What I have seems to be toe out and the article generally recommends a little toe in.

I'm sorry but its not possible to show the servo under the deck.
One servo directly drives one rudder via a metal link. The other rudder is directly slaved to the first via a horizontal plastic bar that shares the servo movement. So both rudder tillers move the same way, same amount.
But viewed from the rear of the boat, the rudders are splayed out by about 10 degrees.
They don't point the same way. If right is straight, the left rudder will turn the boat counterclockwise to port. I guess to go straight ahead, both rudders try to gently turn the boat in opposite directions.
If now the boat happens to twist a little, without any rudder change, the arrangement would tend to correct the twist.
Eg both rudders slightly splayed out. Boat twists to starboard at front. The right rudder is now straight to the motion and the left rudder more strongly opposes it. So the boat self corrects. But if both rudders were straight it would self correct anyhow.
In reverse, things of course work opposite and the situation is unstable. Which is maybe why in reverse it has always been extremely poor and tends to whiz off to one side

Not sure but I think both rudders should be the same If turned L both turn L if R both turn R.On my Irishman the two rudders turn the same at the same time.
Rick

A picture of the rudder setup would be very helpful.

Thanks for that. I can add that if one rudder is straight, then the "misalignment " is such that that the other rudder is turned out. So if R rudder is straight the boat will tend to turn to port.

This will not help too much but my current build, Dusseldorf, has four rudders and they are set to turn exactly the same together.
Peter.