adjusting the rudder

Jackdaw · Jan 11, 2012

That's never a good thing. My old First 235 had a rudder that extended 2 inches below the wing keel. Never hit, but always worried. Modding your rudder might be quite the science project. Lots of forces on the rudder and you don't want it to fail. And if it does it will be at the worst time.

Think about something like this. A bit spendy, but the engineering has been done for you.

http://www.idasailor.com/catalog/product_info.php?cPath=32&products_id=549

RichBone · Jan 11, 2012

I'm familiar with your problem. Other than buying a kickup rudder I don't know what to do about it. You could, I guess, shorten the rudder but that would probably affect boat handling. I don't know why Oday designed it like that. Another consideration about switching to a new rudder is the propensity of the Oday rudders snapping in two; of course it's going to happen when you need the rudder the most. There was much discussion on this forum earlier on the subject. Some saying that it's not 'if' but 'when'. I played with the idea of sheathing the rudder in several layers of 'glass, which should strengthen it considerably. But in the end I bought the kickup rudder from Idasailor and am very happy with it even though it is deeper than the stock one. Plus being a kickup it's easier to clear the weeds it collects. There lots of weeds and shallow water in my area.

Rich

Joe11688 · Jan 11, 2012

I love the kick up rudder on my O'Day 222 but you need to keep in mind that you can't sail your boat with it up as little as 3/4" or you'll experience a lot of weather helm in your tiller. I think that this can cause the blade to flex which probably isn't too good for it.
I can't speak for the O'Day 25 rudder blades but I know first hand that the tip up rudder blades that they put on the O'Day 222s can and will break in time. I broke two of them on my boat. The one I have now is a solid blade that Rudy Nickerson of D&R Marine made for me back in the 1990s. It's still working great for me.
Joe

Sunbird22358 · Jan 13, 2012

One idea would be to cut the bottom 6-8" off the O'DAY 25 rudder (I think that would reduce rudder draft to less than the keel?) then attach an "endplate" to the bottom of the rudder, basically like the wing on a wing-keel, it would extend about 6" or so out from the edge of the rudder on each side and be the same fore & aft length as the rudder. Check out some of Phil Bolger's designs for examples. The endplate "tricks" the water into thinking that the rudder is deeper by trapping the flow along the bottom of the rudder instead of letting it slip off over the bottom edge.

Joe11688 · Jan 15, 2012

I'm not certain about the O'Day 25 rudder blades as far as how they were fabricated but I can tell you about how the 192, 222, and the larger boat rudders were made.
A company that was located in Clearwater Fl. called Foss Foam Inc. manufactured these rudders for O'Day back then. Most of the blades including mine were molded in two pieces, then they were glued together and pumped with Polyurethane Foam.
They break very easy. I know because I had two of them break on me.

The rudder manufacturer warned against the use of dark colors on the blade that could generate heat and cause dimensional changes and cosmetic damage. If the rudder was painted a dark color, they recommended that a white wrapping be placed over it when the boat was out of the water. This was all part of their so called manufacturer's warranty back then. I still have the paper work on this.

We communicated with a guy in the Soviet Union several years ago on this forum who had the same problem with a spade rudder on his O'Day 32.
My old blades had a seam around the edge of them. You could see how the two halves were put together. These seams would open up after awhile and the blade would break in half. I've had a solid blade on my boat since the 1990s and it's in great condition.

Sunbird22358 · Jan 24, 2012

Joe knows more about the internal structure of the O'Day rudders, but my theory for cutting off the lower 9" of the 25 rudder would involve slicing it off 9" from bottom, then sand off and paint for about 6" up from the cut, the area should be roughed up to aid adhesion of the epoxy and fiberglass, then seal the open end with Epoxy resin, with that epoxy still tacky the plywood "wing" can be bonded to the bottom, then strengthened with a couple of layers of fiberglass cloth along the corner where rudder and endplate meet. The endplate/wing would then be sheathed in a layer of FG cloth to protect it. After the resin had all cured, the surface can be smoothed up and if the cloth pattern still shows, another light coat of resin be applied. Once that cures, and is sanded smooth, a few coats of a good marine enamel (or polyurethane paint) if the boat is trailered, or good antifouling paint if the rudder will be left on with the boat moored.

Perhaps, if enough 25/26 owners were interested, D&R could produce a "factory-made" version of this. That would reduce cost (versus a custom rudder) and ensure that it was built sturdy enough.

I wouldn't go with a kick-up rudder just to gain the 9" of reduced depth. I know of other solutions (besides keeping the rudder full depth and being VERY careful?) but I fear that your head is already spinning over my suggested "fix". Check out the rudders on the NIMBLE 20 and 24, I think they employ a "drop-plate".

ebsail · Feb 1, 2012

A problem with shortening the rudder on a 25 will be heeling. As the boat tilts, a good portion of the upper rudder comes out of the water. This leaves only the lower tip of the rudder in the water. If you think of this in extremes, if the boat heeled 90 degrees. no rudder would be in the water. If you shorten the rudder, the boat may want to round up into the wind on a gust and you won't have enough rudder in the water to control it. If draft is really important, get a kick up rudder.

Joe11688 · Feb 1, 2012

pamacm said:
on a oday 25, how can i alter the rudder to make it so that the keel is the same draft or more ? i sail in shallow water and the draft of the keel now is 27 inches and the rudder's draft is 36 inches.

A kick up rudder blade isn't meant for shallow water sailing. If the blade isn't all the way down, you will feel some wicked bad weather helm in your tiller while sailing. This can happen if the blade creeps up 3/4".

If you're sailing along and your tip up rudder blade grounds out or hits an obstacle, the blade can pop up and cause the line to slip through the cleat, or it can cause your tiller to split right down the middle.

This happened on my boat one day during a race. We had three people in the boat while sailing at a good clip. The person steering my boat took her into shallow water and grounded out the rudder blade. The hold down pendant line locked up in the jam cleat on the under side of the tiller and the pressure on the line split my laminated tiller right down the center.

I really don't know what to tell you, but cutting your rudder blade length shorter might have some adverse effects in the way she'll answer the helm when she is healed over in a stiff wind.

Sunbird22358 · Feb 2, 2012

The endplate makes up for the reduced depth, it may even work BETTER than the full depth rudder since it will "hold" the waterflow to the rudder. It had worked for an awful lot of Phil Bolger designs.
I agree with Joe, I wouldn't go for a standard kick-up rudder, the rudder on a 25 is only..what 8" deeper than the keel? The "best" solution (but not the "easiest") would still be a "drop-plate" in the rudder to extend the depth of the shortened rudder blade, the drop-plate would pivot like a centerboard up into the bottom of the rudder in shallow water, but would drop down (maybe 12+ inches) in deep water.

Still wish there was a "cheap and dirty" way to try out that endplate option! I still think it would solve the "too-deep" rudder problem AND the loss of rudder effect when heeling. Maybe I could experiment with a reduced size rudder blade on my DS II? Just replace the stock blade temporarily. That will have to wait until May......

Joe11688 · Feb 3, 2012

That would be a fun experiment Rod and it would be something worth having on the DS11 for shallow water sailing.

adjusting the rudder

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