Undersized Rudder
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Nomad Willy
Guru
Gaston,
The hole is for shaft extraction. I have one but I used three small carrage bolts to plug the hole (mostly) w the cutout and it's above the propwash.
IMO propwash is serious drag from the high velocity water streaming over it. The propwash IS trying to pull the rudder backwards. And that can't help but slow the boat down. And I think the Y or V shaped trailing edges do also. A flat rudder extension increases drak too but only a very very small amount. Ideally I'd like to see bigger rudders on either side of the propwash and to determine if it was less drag. If it was at low speeds w little power on the rudders would be much more effective. Also on following seas. In tight situations at near zero speeds one wouldn't be so dependant on propwash to maneuver. Never seen a boat like that w twin rudders and I'm sure there's a reason why.
The hole is for shaft extraction. I have one but I used three small carrage bolts to plug the hole (mostly) w the cutout and it's above the propwash.
IMO propwash is serious drag from the high velocity water streaming over it. The propwash IS trying to pull the rudder backwards. And that can't help but slow the boat down. And I think the Y or V shaped trailing edges do also. A flat rudder extension increases drak too but only a very very small amount. Ideally I'd like to see bigger rudders on either side of the propwash and to determine if it was less drag. If it was at low speeds w little power on the rudders would be much more effective. Also on following seas. In tight situations at near zero speeds one wouldn't be so dependant on propwash to maneuver. Never seen a boat like that w twin rudders and I'm sure there's a reason why.
Sailor of Fortune
Guru
I think Murraym got it earlier.....
MurrayM
Guru
Forgot to say 'prop' shaft. My bad. Gaston must be a teacher
A Teacher LOL Id shoot my self first
Sailor of Fortune
Guru
some things are implied MurrayM... You should be the winner.
Sailor of Fortune
Guru
we are all winners because of the exchange of information and experience of members. Lots of experience here.
Sailor of Fortune
Guru
nobodies PROP shaft...Didn't you learn your lesson MurrayM?
OP
OP
schrater
Senior Member
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- Matilda
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- Ponderosa (CHB) 35' Sundeck
Update on this OP...
I finally got the modification on my rudder done. They attached a simple 6” strip of steel along the length of the trailing edge of the rudder (creating a 4” extension. Only $300 for the mod, plus labor for pulling/reinstalling.
The results are outstanding! My turning radius is tighter, my autohelm tracks better, and it requires fewer “points” to make a turn in an alley. Keep in mind, this is a single-prop with no thruster, often maneuvering vs current/windage. I highly recommend this mod!
(Unfortunately no pictures)
I finally got the modification on my rudder done. They attached a simple 6” strip of steel along the length of the trailing edge of the rudder (creating a 4” extension. Only $300 for the mod, plus labor for pulling/reinstalling.
The results are outstanding! My turning radius is tighter, my autohelm tracks better, and it requires fewer “points” to make a turn in an alley. Keep in mind, this is a single-prop with no thruster, often maneuvering vs current/windage. I highly recommend this mod!
(Unfortunately no pictures)
WayneDana2
Senior Member
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- Serendipity
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Thanks for posting this up. We have the same type of boat, same engine, no thrusters, hell from your profile picture, we even live in the same marina. We'll look at having this done next haulout. If you could identify who did the work, that would be awesome.
Cheers!
Wayne& Dana.
Comodave
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Was it steel or S/S?
Nomad Willy
Guru
When you get on big following seas trying to not get broached way off course and at full throttle and full rudder deflection are you sure all the components are up to the resulting loads.
Pete Meisinger
Guru
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- Best Alternative
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That may not be the original rudder. There are plenty of "Ponderosas" around just take a look at one. It will give you a reason to walk marinas. Yours definitely looks on the small side.
My rudder is larger but when you are giving the throttle a "burst" to kick the aft around don't be shy. I give mine a kick up to a couple thousand rpm and maintain the burst for a couple seconds. The kicker boost is almost always followed by a similar hit in reverse.
Don't worry about gaining forward momentum. Your boat weighs 20,000 pounds or more, it aint gong anywhere from a two second burst.
But... I would add onto the rudder for the following sea issue.
pete
My rudder is larger but when you are giving the throttle a "burst" to kick the aft around don't be shy. I give mine a kick up to a couple thousand rpm and maintain the burst for a couple seconds. The kicker boost is almost always followed by a similar hit in reverse.
Don't worry about gaining forward momentum. Your boat weighs 20,000 pounds or more, it aint gong anywhere from a two second burst.
But... I would add onto the rudder for the following sea issue.
pete
AlanT
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This reminds me of the most outstanding shipyard repair work I have ever experienced - pasted from our website Alan & Joan's adventures sailing Moonstruck from America to the Mediterranean. Joan Teed's Art. - It concerns an over night rudder repair in Horta, in the Azores (in the Atlantic Ocean 800 miles off Portugal) during an Atlantic Crossing:
We made friends with John and Ashela on JSEA while we were in Ponta Delgada. John is from Vancouver and has sailed most of the voyage so far (from Antigua to Bermuda, and Bermuda to the Azores) with only half of his rudder! The remaining half was giving way as he arrived in Sao Miguel and was repaired last night. At 5:00 Friday evening, the yard started work. They hauled his boat out of the water, examined the damage, removed the remaining parts of fibreglass rudder blade from the Stainless Steel skeleton and welded on a temporary steel rudder made from two custom bent plates of steel. They applied two coats of epoxy, filled the fillets and at 9:30 pm left it to dry overnight, all while John attended the cocktail party in our honor. In the morning (This is Saturday morning) they added a coat of anti-foul and had him back in the water in time to leave with the rest of us at Noon. The Azores is an amazing place to have work done on your boat. I can not think of a yard anywhere that would have taken on work like that on a Friday evening and had it complete the next morning!
2 pieces of stainless about 10" X 21"
bent at 15 degrees
total cost about $80.00 Cdn (thats about $4.00US )
Two SS through bolts with spacers about $7.00
1/2hr. Installation
Massive difference in slow speed handing and even gained some steering in reverse.
bent at 15 degrees
total cost about $80.00 Cdn (thats about $4.00US )
Two SS through bolts with spacers about $7.00
1/2hr. Installation
Massive difference in slow speed handing and even gained some steering in reverse.
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