Centaur rudder skegs

[dylanwinter]

Harmony - Centaur 1 - had a skeg on the rudder

Lily M - Centaur 2 - has no skeg

If I let the tiller go on Harmony when under power she tracked beautifully

On lily M if you let go of the rudder it "overbalances" and shoves herself hard to port or starboard

is this normal?

the bungeomatic solves the problem but Lily M does not feel as nice to steer as Harmony with the skeg

anyone else found the same symptoms?

D

 

[aquaplane]

I have only sailed Chiron which is a late Centaur with skeg.
I can't say that I tack much when motoring.
I don't have to fight prop walk though, I can feel it but it's minimal.

 

[dylanwinter]

I have only sailed Chiron which is a late Centaur with skeg.
I can't say that I tack much when motoring.
I don't have to fight prop walk though, I can feel it but it's minimal.

Centaur 3 will deffo be a later one.

Jon, who bought Harmony, is going to come sailing with me this autumn on the Skegless Lily M - it will be interesting to see if he feels the same way

 

[neil_s]

My Seal 28 does it - and she has a small skeg too! I think it's a case of swings and roundabouts - you have to hold the tiller all the time the engine is going but the boat is also exceptionally manouvreable. No problem getting into the marina berth and such like. There is also another advantage - not many boats have brakes but you can use your lack of directional stability to stop very quickly - just put her in neutral, let the tiller slam hard over and the boat will spin around through 180 degrees and stop. This also works with the sails up, of course, and can be used to do a very slick under-sail mooring pick up. All this is beside the point if all you want to do is get your pullover, though!

 

[TC Tuckton]

"Centaur 3" ?

 

[dylanwinter]

"Centaur 3" ?

I expect to keep this one for four years, run out of money, use Katie L to explore the weslh coast and up the shannon and then buy a thof centaur for the channel iislands and brittany

or I might win the lottery

 

[dylanwinter]

My Seal 28 does it - and she has a small skeg too! I think it's a case of swings and roundabouts - you have to hold the tiller all the time the engine is going but the boat is also exceptionally manouvreable. No problem getting into the marina berth and such like. There is also another advantage - not many boats have brakes but you can use your lack of directional stability to stop very quickly - just put her in neutral, let the tiller slam hard over and the boat will spin around through 180 degrees and stop. This also works with the sails up, of course, and can be used to do a very slick under-sail mooring pick up. All this is beside the point if all you want to do is get your pullover, though!

you may be right

this one seems even more maoeverable than the one with the skeg

count my blessings

 

[bitbaltic]

Used to sail on a bigish X-yacht in Denmark, tiller steered 34 or 35 footer. Had the most awful balance on the rudder when under power, trying to overpower and twist the helm one way or the other in an alarming fashion when steering in a straight line in a flat sea; the boat basically would not motor acceptably. No idea if there was some prop or damage issue but I think not as it was owned and maintained by a corporate yacht club. It made the boat stand-out dreadful. Presumably no skeg on it either!

Don't suffer any tracking problems, under power or not, with my spade ruddered Hanse though.

 

[ghostlymoron]

I wonder if the rudders on the two are identical. A skeg certainly gives more directional stability but maybe the rudder on the skegless boat needs an extension on the leading edge to give better balance.

 

[rob2]

Surely if the rudder slams across it is overbalanced and an extension to the leading edge would make it worse? My own boat has a skeg mounted rudder with little balance area, but the skeg makes it uneccessary. However, give her a handful of revs in reverse and you need to be well braced to stop the tiller slamming across. Of course, with the water flow reversed this is a massively unbalanced rudder!

Rob.

 

[VicS]

I wonder if the rudders on the two are identical. A skeg certainly gives more directional stability but maybe the rudder on the skegless boat needs an extension on the leading edge to give better balance.

Early boats , until the mid 70s, had unsupported spade rudders. Later boats had a semi skegs. There seems to have also been some variation in the design of the spade rudders. Lliy M's rudder appears to be slightly different to these even.

I think Dylans use of the expression "over balances" is giving the wrong impression as to what is happening.

None of the designs pictured above has any great balance area . 10 to 15% gives what is termed a "semibalanced" rudder.
The first "swept back" design shown above has no balance area at all. My rudder, athough transom mounted, was originally a swept back design similar to this. It is not now . It has 12.5% balance area!