21 replies to this topic

[GIULIETTA1]

So my good buddy just boat a used 40' cruising boat. We went sailing last night and the thing wants to turn left the whole time. Feels good on port, but it wants to bare away into a round down on starboard, even up wind in 20 knots!
What are the possible causes of these symptoms?
Thanks.

[R Booth]

So my good buddy just boat a used 40' cruising boat. We went sailing last night and the thing wants to turn left the whole time. Feels good on port, but it wants to bare away into a round down on starboard, even up wind in 20 knots!
What are the possible causes of these symptoms?
Thanks.

Take it to P/A.....

[movable ballast]

Does it have NASCAR stickers? Could be lots of bad (read expensive) things bent rudder post or rudder, bent keel...

[couchsurfer]

...other than the keel rudder possibly being mis-shaped,or mis-aligned,you might check if the mast is leaning to one side more than the other,simply take the main halyard and measure to a similar point on both gunnels
....that'd be a good start,,,,,,,,try -simple- first!

[Trevor B]

Maybe getting some people on board who know how to sail might help......

Good luck, obviously something not lined up with something else. Or, sometimes excessive balance in the rudder can do some weird things.

[SEMIJim]

So my good buddy just boat a used 40' cruising boat. We went sailing last night and the thing wants to turn left the whole time.

I think I see the problem: Your good buddy is trying to sail a car. Prolly needs a front-end alignment .

Jim

[SHNOOL]

Does the boat have Obama stickers on it?

Seriously though, sounds like a big problem as said, keel, rudder, mast any or all seriously out of alignment. Mast is easy to see, others, not so much.

Don't forget to check to see if you're dragging some underwater crud/logs/houses portside.

[Bob Perry]

What they said, i.e. something is bent. Is it a tiller or a wheel steered boat?

[soak_ed]

Get DM off of the rail.

[Delta Blues]

The boat is perfect for fleet racing, all marks are rounded to the left.

However if you're going to match race with this boat, you've got a big problem.

[Asymptote]

I had that symptom on a boat I owned. Suddenly the boat had serious helm on one tack and neutral helm on the other. The cause ultimately was discovered to be that the rudder (painted with black baltoplate) deformed when it was hauled out and the summer sun hit one side only. We found the foil had a 1/4" deeper chord depth on one side than the other. This was a rudder that had been very carefully templated. Apparently the foam core was saturated and the increase in vapor pressure under heat bulged the foil out.

That chord depth difference caused a tremendous amount of helm. Refaired the foil and everything was fine. Since then, we always cover our rudder on haul out with white plastic. The yard does it as standard practice now.

[MoeAlfa]

Once sailed a J/32, which had a similar problem whenever the water tank under one of the settees was filled.

[couchsurfer]

I had that symptom on a boat I owned. Suddenly the boat had serious helm on one tack and neutral helm on the other. The cause ultimately was discovered to be that the rudder (painted with black baltoplate) deformed when it was hauled out and the summer sun hit one side only. We found the foil had a 1/4" deeper chord depth on one side than the other. This was a rudder that had been very carefully templated. Apparently the foam core was saturated and the increase in vapor pressure under heat bulged the foil out.

That chord depth difference caused a tremendous amount of helm. Refaired the foil and everything was fine. Since then, we always cover our rudder on haul out with white plastic. The yard does it as standard practice now.

.....I'll bet!!

[R Booth]

I had that symptom on a boat I owned. Suddenly the boat had serious helm on one tack and neutral helm on the other. The cause ultimately was discovered to be that the rudder (painted with black baltoplate) deformed when it was hauled out and the summer sun hit one side only. We found the foil had a 1/4" deeper chord depth on one side than the other. This was a rudder that had been very carefully templated. Apparently the foam core was saturated and the increase in vapor pressure under heat bulged the foil out.

That chord depth difference caused a tremendous amount of helm. Refaired the foil and everything was fine. Since then, we always cover our rudder on haul out with white plastic. The yard does it as standard practice now.

.....I'll bet!!

You should see what happens when you stand a slab door (hollow or solid core) outside, leaning against something, in the hot sun. Great way to make escape hatches for flying saucers......

[Kenny Dumas]

Might be able to diagnose whether it's above or below the waterline by motoring without sails up. Does it go straight when flat? Then heel it each way. Of course some boats (eg Catalina 30) have monster prop wash on the rudder. Other indicators:
How about Dead Down Wind (heeled - not heeled) under sail on each jibe, etc?

[Palo]

My good buddy just told me about his post...so it is my boat...i want to figure out what is happening, as rounding down on starboard does not feel right.... But it does take maybe 10-15 sec to start tracking other than dead straight.....it is that it then progressively got quicker going down......say Trevor.....are you being harsh on your bro, or me?

I will try some motoring tests, as well as dead down when I get a chance....

[Trevor B]

My good buddy just told me about his post...so it is my boat...i want to figure out what is happening, as rounding down on starboard does not feel right.... But it does take maybe 10-15 sec to start tracking other than dead straight.....it is that it then progressively got quicker going down......say Trevor.....are you being harsh on your bro, or me?

I will try some motoring tests, as well as dead down when I get a chance....

My bro AND yours.

[SemiSalt]

I will try some motoring tests, as well as dead down when I get a chance....

Just a suggestion, get going about 5 knots and idle the engine to see how she goes just coasting.

[GIULIETTA1]

What they said, i.e. something is bent. Is it a tiller or a wheel steered boat?

Thank you Sir.
It is a wheel boat with very little feel or friction in the system.

[Asymptote]

My good buddy just told me about his post...so it is my boat...i want to figure out what is happening, as rounding down on starboard does not feel right.... But it does take maybe 10-15 sec to start tracking other than dead straight.....it is that it then progressively got quicker going down......say Trevor.....are you being harsh on your bro, or me?

I will try some motoring tests, as well as dead down when I get a chance....

Exactly my symptoms. See post a few up. Get going fast enough to center your prop in flat water. Hold the helm center and let it do what it wants. Once the asymmetry takes hold, the rate of turning accelerates.

[Innocent Bystander]

It's already been suggested to do it in neutral. That's important as you want to elongate any prop wash impact.

[Ishmael]

It's already been suggested to do it in neutral. That's important as you want to elongate eliminate any prop wash impact.