How to Repair and Restore a Rudder

Rudders damage easily. Although they work similar to a keel, they aren’t nearly as tough. If you dry sail, the edges can accumulate nicks and dings in the fiberglass from loading and unloading. The rudders of some sailboats can hit the outboard motor’s propeller if you’re not careful. Add in accidental groundings, storage damage, and stress cracks and it doesn’t take much time in water to make the wooden core swell and damage the rudder even more. Without repairs, a weakened rudder can even break into pieces under stress. It pays to protect your rudder.

Before I continue, a bit of legal housekeeping. This post contains affiliate links. That means I receive a small commission if you make a purchase using those links. Those commissions help to pay the costs associated with running this site so that it stays free for everyone to enjoy. For a complete explanation of why I’m telling you this and how you can support this blog without paying more, please read my full disclosure.

Example of a damaged upper trailing edge
A badly damaged upper trailing edge. Some chips are completely through the fiberglass skin.
Example of a crack caused by a swollen core
A crack caused by a swollen core lets water in quickly and out slowly
BEFORE - lower trailing edge
A worn lower leading edge. The wood core is exposed and delaminating.

If your rudder is showing any bare wood, has deep nicks in the edges, or has swelled and cracked the fiberglass at the edges, you should repair it while you still can. All of these kinds of damage are easily repairable by the do-it-yourselfer for a small fraction of the cost of a new rudder.

It’s just like doing auto body work

If you’ve ever done any auto body work, you know the goal is to build up and restore a smooth shape to damaged surfaces. It’s the same with your rudder but the finish quality doesn’t have to be as perfect.

Follow these steps to make your rudder smooth and watertight again:

1. Start with a 4″ handheld grinder or similar power tool to remove all of the rough and damaged fiberglass down to solid material.  Also remove all damaged wood core material. This might seem overly aggressive but the repair won’t last unless it’s built on a solid foundation and a grinder will get you there fast. By opening up the rudder’s “envelope”, it will dry out faster.

2. Let the wooden core dry out as much as possible. You don’t want to trap moisture in the core where it will dry rot. If you lay up your sailboat for the off-season, that’s a good time to dry out your rudder. Finish the repair before the start of the next sailing season.

3. After the core has dried thoroughly, use a random orbital or similar power sander to feather the ground edges back a couple of inches all around and to remove any paint so that the epoxy patch will stick properly to the original fiberglass.

Sanding the lower edges before fairing
Sanding the lower edges before fairing

4. Mix some thickened West System or an equivalent epoxy and build up the ground and sanded areas to their original shape.

5. With a power sander or sanding block, carefully smooth the patched areas to match the surrounding surfaces and edges.

Upper trailing edge built up with epoxy
Upper trailing edge built up with epoxy
Lower leading edge built up with epoxy
Lower leading edge built up with epoxy
Lower trailing edge built up with epoxy
Lower trailing edge built up with epoxy

7. Apply a barrier coat of one-part or two-part (preferred) polyurethane paint over the repaired areas.

Repaired edges with new barrier coat paint
Repaired edges with new barrier coat paint

6. Fill small cracks above the water line with Capt. Tolley’s Creeping  Crack Cure.

Top rear crack sealed and painted
Top rear crack sealed and painted

7. Last, re-apply ablative paint or a polyurethane topcoat to match the rest of the rudder or hull. If you keep your sailboat in the water, ablative paint can minimize the growies. If you dry sail or remove your rudder when you’re not sailing, ablative paint gives no benefit and will just transfer to everywhere you don’t want it. I reapplied ablative paint to this rudder but I sanded it off a year later and applied a gloss white polyurethane when Summer Dance got a different color bottom paint job.

8.  Now is a good time to remove, clean, polish, and rebed all of the rudder hardware with butyl tape. If the tiller bushings are worn, read How to Replace Worn Tiller Bushings.

Now that you have a restored and sealed rudder, take good care of it and it will take good care of you!

Would you like to be notified when I publish more posts like this? Enter your email address below to subscribe to this blog and receive notifications of new posts by email. You will also receive occasional newsletters with exclusive info and deals only for subscribers and the password to the Downloads page. It’s free and you can unsubscribe at any time but almost nobody does!


16 Comments Add yours

  1. m4n4ger says:

    Hello from the UK! The rudder on my Jaguar 22 is the pivoted type to cope with grounding when the keel is lifted. It’s made from dense dark wood (mahogany I think) and it weighs a TON! It worries me having all that weight hanging off the f/g transom plus the outboard – it flexes the hull… I’ve seen some of the Gucci lightweight racing replacements available in the States for mega-bucks, but I wondered if you’d ever considered making a replacement lightweight rudder $tingy-style from (say) stainless or aluminum frame,with glass fibre coverng over foam, or similar? It would be a fascinating project!

    Keep up the good work!

    Mike (Tamariu) Jag 22

    1. Hi, Mike

      Your description makes me wonder if a previous owner made your kick-up rudder blade himself. No factory C-22 rudder that I’ve ever heard of was made of hardwood. I can’t imagine why the UK builder would go to that expense and being a licensee of Catalina Yachts, they would be legally bound to stick to the factory designs, materials, and methods.

      As a matter of fact, I do have tentative plans to make a balanced rudder similar to what you describe or possibly of solid, lightweight cedar, so stay tuned!

      1. m4n4ger says:

        Sounds good – I’ll keep watching!

  2. Richie says:

    Great informative article. Enjoy all your postings, have learned a lot.

  3. Jeff Powell says:

    Has anyone ever made a new rudder solely out of wood?

    1. Hi, Jeff

      I’ve seen one fella’s rudder that he made out of mahogany and it weighed a ton. Others have attempted to make balanced rudders to replace the stock one. Rudder Craft makes high performance replacement rudders but they’re pricey and they also aren’t class legal for racing. Building a balanced rudder with conventional techniques is on my to-do list so you might see it here someday!

      1. Jeff Powell says:

        Well, I am a novice sailer at best. I won’t be racing, so a little extra weight won’t hurt much. From the looks of the rudder I have, it is has a wooden core in it. I just aquired the sailboat with some restoration needed. The rudders bottom has the fiberglass rubbed off. I have access to some cedar planks the same size as current rudder, so I was thinking of a nice winter project. Boat stays trailered when not in use.

      2. Cedar would be strong, lightweight, and rot resistant. Go for it and send me some pictures when you’re finished and I’ll add them to the Reader’s Gallery.

  4. Ed says:

    Here is a link that I hope will take you to my pictures of the Sage 17’s rudder system in the Google ‘Photos’ cloud:
    (I prepared some comments before I searched for the photos and the text disappeared when I returned…maybe they got posted…)

    I really appreciated and look forward to the clear and concise project posts!


    1. Very nice. Can you describe how it works here? It looks like when you raise the tiller handle, the rod rotates the blade up and the bungee holds it in position. What did you make the blade out of, mahogany?

      1. Ed says:

        I think you understand it better than I do…and as described here: (see tab on stern & rudder features)

        As I recall, the Sage rep said it took some experimentation to get the balance just right for the length of and attachment points for the rod on blade and tiller. You will see the rudder is outsourced to another manufacturer…I wonder if they have branched out to other boats?! The blade is mahogany, they note…

        It doesn’t look to like it would be that hard to replicated, if you have the capability to fabricate/locate stainless parts.
        I’ll be interested to read how you’d do it, when you’ve replicated a similar designed for your boat!


      2. Ah, I understand now with your link to Sage Marine. I thought you made the rudder yourself.

        I was planning to make a balanced, fixed-style rudder but now after seeing how yours is made, I just might make a kick-up rudder instead that will lock up for trailering!

        Thanks, Ed

      3. Ed says:

        You bet. Just a little payback for all your great info. If I hear back that J O Boatworks will customize the design to meet other boats, I’ll let you know!

    2. Jeff Powell says:

      Well, we are almost finished with the rudder out of cedar. Instead of one solid piece we had to use 3 pieces thick of varying lengths that we planed and glued together then molded and sanded then applied more that 10 coats of marine varnish. Hardware is basically all we have left. Only thing, we we got involved and forgot to take very many pictures until the almost the finished product…sorry I can’t figure out how to post a picture here…

      1. Sounds fun, Jeff. Take the best pictures you can and enter the 2017 Stingy Sailor DIY Project Contest coming soon!

  5. Edward A. Bachmann says:

    If you want to have a balanced kick-up rudder like JO Woodworking fabricates for the Sage, contact him from his website.

    We emailed numerous times to confirm he could get the system to work for my setup and pricing seems fair! I am hoping my tax refund can pay for one for my Venture 21!

    Happy sailing in 2017!

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s