self centering rudder/tiller?
- Thread starter RussC
- Start date
My Gloucester's rudder is built similar to yours, and when it's pulled tight against the stop it's raked forward a little. Tiller effort seems light to me, but I have nothing to compare to.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,261
I'm a little surprised by this whole conversation. As long as rudders hinge forward, they are naturally self- centering. Some better than others. The reasons for needing a tiller tamer are, as Jon says, sail trim and clr position.
Anyhow, interesting discussion, regardless.
-Will (Dragonfly)
Anyhow, interesting discussion, regardless.
-Will (Dragonfly)
My take on the discussion was based on "balancing", not necessarily "centering". I was also differentiating between balance and weather helm or lee helm, which is obviously influenced by sail trim. My impression was that as rudders get larger, the effort of simply steering increases when the pivot point of the rudder is out in front of the rudder, such as it typically is for stern hung rudders. Others have correctly pointed out that the rake and shape of some stern hung rudders help improve the balance, making steering easier with just a bit less pressure all on one side of the pivot point. Obviously, a rudder can't be pivoted around the center of a rudder, it would cause the rudder to be a brake, like turning a paddle sideways. I thought that by placing some portion of the leading edge of the rudder ahead of the pivot point, the force on the leading edge helps make steering a bit more balanced or easier. However, too much shape in front of the pivot point acts like a brake. Perhaps, racing boats don't like "balanced" rudders because the objective of making steerage a bit easier compromises speed. What say you?
Scott, I think your take on balanced design of rudders is excellent. However, where it hinges does not make it a break. How far over it goes makes it a break. Some leading blade on the post will make it easier to handle.
-Will (Dragonfly)
-Will (Dragonfly)
I think it has more to do with how the rudder feels. When a boat is perfectly trimmed an unbalanced rudder will have a neutral feel, it feels kind of loose and sloppy. If the trim is off, it will put pressure on the helm letting the helmsman know immediately that something is out of kilter, could be course, could be wind direction/speed, waves, weight balance, etc.
A balanced rudder takes some of the feel out of the rudder's functioning, combine that with a wheel and the feedback from rudder gets diminished. To make steering easier a longer tiller is used.
For the extreme opposite condition, consider backing in reverse. In this case the rudder is completely unbalance with the pivot point on the "aft" side of the rudder. There is not much feel to the rudder when it is centered, but put it off center a little and there is a tremendous force often jamming the helm hard over.
Older thread but here is my 1970 C&C36R Rudder.
She is very forgiving when flying the kite.
The pic is when I discovered and rescued her.
Cheers
Bob
She is very forgiving when flying the kite.
The pic is when I discovered and rescued her.
Cheers
Bob
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There is a sailing drill in which you use the sails to steer the boat. I did it on my Bandit 15. You put the boat on a close reach, not hard on the wind so you don't have to deal with stalling. You adjust the sails so that there is as little helm as you can and tie the tiller to hold it there. Then you adjust the trim of the main and jib paying attention to how the boat turns. Pretty soon you get the hang of it. This isn't the same as sailing without a rudder which is needed to reduce slippage and to lever the stern against the keel.
I agree with Jon in that most helmsmen over use the rudder. It takes a crack crew with great communication skills to sail using the sails to steer. Helmsman and trimmer must be on the same page.
I agree with Jon in that most helmsmen over use the rudder. It takes a crack crew with great communication skills to sail using the sails to steer. Helmsman and trimmer must be on the same page.
Hi Andrew......Myself and two crew were sailing in a nice 35 knot breeze (for about 7 hours) and we noticed that we could let go of the wheel and she would carry on through the waves swimmingly..
This old boat won her class in the 1971 Chicago-Mac and beat up many a competitor for years in the Great Lakes. An absolute masterpiece and she can cruise like a champ. That rudder makes her a dream on all points (especially downwind) except backing up in a slip with the tiny folding prop and large distance to the foil..you have to give it a good initial shot and then go to zero revolutions on the screw....; ) looks like your sailing a nice one yourself.! Cheers, Bob!
This old boat won her class in the 1971 Chicago-Mac and beat up many a competitor for years in the Great Lakes. An absolute masterpiece and she can cruise like a champ. That rudder makes her a dream on all points (especially downwind) except backing up in a slip with the tiny folding prop and large distance to the foil..you have to give it a good initial shot and then go to zero revolutions on the screw....; ) looks like your sailing a nice one yourself.! Cheers, Bob!
Returning to my dad's home for a visit sometime in the '80s, he loaned me his Ford Probe to go visit my friend in Santa Rosa.
Driving away from his house in the hills above Mill Valley, Ca I was having fun driving this sporty car on the winding roads. I knew these roads well, having driven them since I got my learner's permit, and as I came into a tight curve I turned the wheel, dropped a gear and slid my hand around the wheel for better control. Needless to say, I almost died that day, as my dad had failed to mention the car had a self centering wheel!
I didn't like it on the car, always having to fight that wheel, but on a boat it seems unimaginable. How could you tack, letting go of the helm to loose a sheet or pull one in, never mind doing both and keeping an eye out for other boats?
Thanks, but no thanks.
Driving away from his house in the hills above Mill Valley, Ca I was having fun driving this sporty car on the winding roads. I knew these roads well, having driven them since I got my learner's permit, and as I came into a tight curve I turned the wheel, dropped a gear and slid my hand around the wheel for better control. Needless to say, I almost died that day, as my dad had failed to mention the car had a self centering wheel!
I didn't like it on the car, always having to fight that wheel, but on a boat it seems unimaginable. How could you tack, letting go of the helm to loose a sheet or pull one in, never mind doing both and keeping an eye out for other boats?
Thanks, but no thanks.
I've read and re-read this and still can't come to any conclusion but that both scenarios are gross exaggerations of essentially nonexistent problems. every car built since the 20s has (+ or -) caster designed into the front suspension to provide some degree of "self centering". if you have to "fight the wheel" to maintain control then something is drastically wrong with the car. same with a boat. we're not talking about massive amounts of force here, in either case. Scott t-bird had the right idea when he correctly understood my original post that the issue was more one of balance than of actual centering. but it's been an interesting discussion non-the-less.
Yes. This appears to be a reference to rudder design. A balanced has the center of force at the rudder shaft while most modern boats have it aft of the shaft.
I wonder if what I'm about to say (attempt) has any bearing on the discussion? In a big ship and in an airplane, when you turn the wheel (or stick or tiller) in effort to turn the pointy end port or starboard, at some point you will have to apply counter helm to retard the motion and steady up on the new heading. In a car you do not do this because you are turning the wheels and going through a corner and turning the wheels more to steer through the rest of the corner. When driving the car normal there is no counter helm. Yes/No?
I'm not certain I follow. When I drive something and make a turn I always have to return the wheel to the center position.
The reason boats have balanced rudders is to reduce the effort needed to steer the boat. If you have ever steered a boat like a Tanzer 22 with a transom hung scimitar shaped rudder you will quickly realize this.
A small about section of rudder forward of the rudder post or pintles serves to reduce the leverage of the aft half of the rudder, thereby reducing pressure on the helm. If the sails are balanced the rudder will hold the center position for a while until something happens (wave, wind gust, wind shift, etc.) that causes everything to go out of balance.