Rudder stops

Please see the post RE new 7.9 masts

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Secondreef
Posts: 4
Joined: Sun Apr 30, 2006 12:20 pm
Location: Portland, Or.

Rudder stops

Post by Secondreef »

Hi all,

I have taken delivery of a new rudder. This rudder is slightly smaller from the front to the back of the head. The original rudder would stop swinging forward when the head came into contact with the gudeon bracket. This new rudder swings forward quite a bit more.

My question to you all, since I have never seen another 7.9, is it typical for the forward swing of the rudder to stop when this contact is made, and then the pivot bolt is tightened in that position?

Or, do you rely only on the tension from the pivot bolt to hold the rudder down in some other position?

If I were to use this rudder as is, it would have to be held in the down position only by the tension of the pivot bolt. I can't imagine that being sufficiant.

Also, what keeps the rudder from swinging back just that little bit untill it makes contact with the hold down pin.....I guess the whole settup has me concerned.

My new rudder saga has not been real pleasant so far, as UPS mangled the thing, and won't cover the damage, as well as this business of it not fitting quite right..... :(

Maybe this is all par for the course..as they say...I've never had to replace this type of gear before.

Thanks for any input you have,

Mark
S2 7.9
#381
Iskra
Tom Line
Posts: 137
Joined: Mon Jan 13, 2003 10:32 pm

Post by Tom Line »

Not par for the course at all. It sounds like you've had a rough time.

You want the leading edge of your rudder to be perfectly vertical in the water.

For me, that's all the way down, then pinned. The pin has worn a slight groove into the top of the rudder that I simply fill from time to time to keep the angle of attack correct.
Tom Line
Hull 421
Grrr...
8)
Jim Kloss
Posts: 175
Joined: Sun Feb 02, 2003 5:59 pm

rudder fit

Post by Jim Kloss »

My rudder, factory original, will swing all the way forward and rub the bottom of the boat, which is obviously not a good idea. Tension on the pivot bolt is the main hold down, but you really do need to rely upon the stainless steel retainer pin when it starts to blow. You can insert a wooden shim between the pin and the rudder head to spread the load and tension a bit more.

Out of curiosity, who made the rudder? I'm sure other skippers would appreciate your opinions after you've gotten it wet.

Jim Kloss
s/v Ambivalence
S2 7.9 #8
Secondreef
Posts: 4
Joined: Sun Apr 30, 2006 12:20 pm
Location: Portland, Or.

Post by Secondreef »

Ahaa!

As I thought. Three different boats, three different fits...... :shock:


Well thanks for the replies, it's comforting to know I'm not really getting the short end of the stick...well, maybe not the sharp end anyway.


I am fabricating a stopping bumper out of that hard white material...????
Star board I think it's called. It will fit between the cheek plates and provide a positive stopping location on the forward swing.

The reason I had to replace the rudder was that the head had severely cracked where it contacts the hold down pin, and it was a long wet winter before I discovered it. Shame on me. The rudder was REALLY heavy by the time I got it off, and things didn't look good on the inside when I ground it open.

Phil Locker of Phils Foils built a new one. It looks pretty good, not as fair as the one that was on the boat, but I was not the original owner, and I believe the original owner did an excellent job of fairing the boat.

It will be another 2 weeks before I get it all back together and in the water again....uhgggg. I'll post my thoughts then.

Thanks for the replies,

Mark
S2 7.9
#381
Iskra
Secondreef
Posts: 4
Joined: Sun Apr 30, 2006 12:20 pm
Location: Portland, Or.

Post by Secondreef »

After sanding... barrior coating, 2 coats of VC17, re anodizing the cheek plates, revarnishing the tiller and teak blocks.....whew! More work that I anticipated months ago when I noticed the original damage....

Sure looks real sweet. 8)

A fair bit lighter than the original too. :)

Had her out yesterday in 8-11 knots. Not a complete test at the extremes, but never the less, great to be on the water again. :D


With the addition of the forward stop bumper, I was able to adjust the down position to a point where, now, the pressure on the tiller from weather helm is greatly reduced. The boat now "feels" better ballanced than with the original rudder. (maybe the original could have been set up this way too though.)

Good rudder!
S2 7.9
#381
Iskra
Tom Line
Posts: 137
Joined: Mon Jan 13, 2003 10:32 pm

Post by Tom Line »

Secondreef, good for you!

Make sure that if you plan on doing nationals that you weigh your assembly in advance. There's a weight specification on them now.

I was very suprised to find I was within 1/2 pound of the limit when I measured mine - I was looking forward to making it lighter because it's a beast for one person to get it on the back of the boat.
Tom Line
Hull 421
Grrr...
8)
dave
Posts: 727
Joined: Fri Jan 02, 2004 10:39 pm
Location: Little Rock

rudder stop

Post by dave »

Second reef, if you have the ability/facilities to put the boat up on a lift [as I did] the job becomes simple and straightforward. set the boat down on some pads with the trailing edge of the keel perfectly verticle, fore and aft and side to side. The side to side might not seem neseccary, but if it's not REAL close to right you can get screwy readings on the level if the thing is not held on the back of the keel EXACTLY perpindicular to the centerline of the hull. Once you get this set just set the trailing edge of the rudder the same as the keel and drill another hole behind the pivot bolt for a REAL lockdown bolt/pin [class legal]. I used to use a wedge too and just eyeball it. There's no comparison to how the boat feels from then until now. I raced Cats for 15 years and on a cat you adjust the rudder rake to balance the helm. Too far under the boat and the thing will go into autogybe on a sreaming reach or downwind, too far aft and you have two handed weatherhelm. On a 3' long rudder blade that difference amounts to about 3/16" - 1/4". Most monohull folks just get the thing somewhere close and call it good enough. That's a BIG mistake if you want the boat to handle well/safely. You could probobly do this in the slip on a calm day, just using someone topside to do the fore/aft and side to side balancing but you would need a pneumatic drill.

Dave
Paul Latour
Posts: 13
Joined: Mon Mar 22, 2004 10:49 pm

Post by Paul Latour »

Call me at 615-336-7900; leave your name and number if I don't answer. I have a great deal of experience now with rudders on S2 7.9; too much to discuss by email.

Paul Latour
ITCH
Nashville
paullat@comcast.net
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