What are sailboat rudders made out of?

[saurav16]

I have a catalina 27 and the rudder along the forward leading edge has a crack
The rudder seems to be made out of something hard (steel?) and then something soft like fiberglass around it. I think I got the crack from water getting in and freezing in winter. Any ideas on how to fix it? Thanks in advance. I have a picture which I will post.

[Rockter]

Mine is glass-fibre over mahogony, with two stainless stringers and a big U-section, bolted through.

[US27inKS]

On a Catalina, I would bet on an aluminum or stainless rudder stock with a "flag" welded on to it. Around that will be a foam core with a fiberglass shell over that. If water gets in through damage to the fiberglass or a poor seal around the rudder stock, it will freeze and swell breaking the fiberglass and possibly breaking the core loose from the stock.

If the core appears to be well attached to the stock then it may be repairable. Start by drilling drain holes in the bottom, and fixing where the eater got in. After you are satisfied that the core is dry (it may be days or weeks) you can start your fiberglass repairs. If you've never done fiberglass work, get a book or video, or a friend who knows how.

[CS271409]

I had a crack on the leading edge of my rudder on my CS27 a few years ago. It was between the lower and upper gudgeons with some below the waterline and some above. My rudder is outboard so it was fairly easy to remove and bring home for the winter to repair... I don't think the Catalinas are outboard mounted so yours may be tougher to remove.
Anyway, I ground out the crack and made a bevel using an aggressive sanding disc and then applied progressively wider layers of glass mat over the area to fill the bevel and then overlap int the sound area of the rudder. I faired it in and applied Interprotect 2000 to it and then gel coat to the portion above the waterline. It has worked well for a couple of seasons under some tough conditions. You'll need to lightly sand off all of the bottom paint wherever you plan to adhere fibreglass. Take it down to the just a hair below the gelcoat.
I agree with US27 above to drill some drainholes in the bottom of the rudder to let all water out. The inside of my rudder was bone dry when I did the work but it sat in a dry and warm house for four months over the winter before I made my repairs.
Good luck.

[majortoo]

You might check the Catalina owner web site. I hear they have a strong support system.

[sailingdog]

Many rudders are fiberglass around a steel or aluminum stock with a "web" framework that is welded to the stock and that the fiberglass is laminated over. A big problem on many rudders is that they aren't sealed properly and water gets in and causes the rudder stock or webbing to corrode and fail.

Most fiberglass rudders aren't solid fiberglass, but foam or wood cored, and you need to know if the core is delaminating or rotting before you try to repair the rudder. If it is, then repairing the rudder is probably a waste of time and materials unless you re-build it completely.

[CharlieCobra]

Mine's solid mahogany.

[saurav16]

thanks for the replies, it seems that there is rusty looking water leaking out.

[sailingdog]

Saurav-

If the water is rusty looking, chances are pretty good that the interior webbing that the rudder attaches to the rudder stock on is probably rusty and shot. The interior is probably pretty saturated as well, so just filling the gap isn't going to help much.

[saurav16]

I had the rudder laying on it's side on my work table over night the table had some water on it. I drilled 3/16" holes (4 of them) along the bottom leading edge of the rudder and sat it near the furnace of my house. When I drilled the four holes the material that came out was like white powder I assume its epoxy/fiber glass was bone dry. I think the rudder should be ok structurally. I tapped it with a hammer seems to sound out ok except where the crack is. Is there any way to tell for sure if its ok inside?