Rudder Repair

[Rick]

Well, I've repaired the four holes in the hull of my Aquarius 21 and removed the rusted centerboard. Thanks for the advise on those projects. Next, I need to repair the rudder. It had a significant crack on both sides near the top of the fiberglass section of the rudder. I've posted pics of both sides.





The rudder didn't feel loose, as if the metal or welding inside was broken. Because of the size of the cracks, I decided to open the rudder up in the area of the cracks to try to determine the cause. Here are the pics after I removed the fiberglass cover.





The metal rod isn't cracked or detached, although it's rusty. The wood is fairly solid and the resin was hard. The only things I noticed was that there were several voids where there was no resin in the area of the cracks. Also, the fiber glass covering leading and trailing edges of the rudder are worn and the two glass sides have cracks between them, so water would have gotten into the rudder in those areas. Here's another pic



So, my questions are whether I can just repair the cracked areas with epoxy and glass, or should I seperate the two sides of the rudder, clean up the metal, maybe replace the wood, epoxy them in place and then glass the rudder back together... or just spend the $600 for a new rudder. I'm trying to keep expenses down ( there's a surprise!) since my project list includes replacing all the standing rigging, rebuilding the interior, etc ...

Sorry for the size of the pictures - I used freeimagehosting, but couldn't figure out how to reduce them before uploading. I'd appreciate some assistance there also. Thanks.

Photos resized on your behalf.

Rick

[Jason K]

If you email the pictures I'll resize and host them for you.

info (at) triton218 (dot) com.

[Tim]

Do you think you can cut and grind back the exposed areas in order to obtain clean, solid, and sturdy laminate as a base for your repair? This is paramount in terms of determining whether you should repair your rudder or not.

Most rudders like yours are built with two halves, joined together with a mishmash of fiberglass resin and choppings--which is exactly what yours looks like. As a result, the material inside the rudder tends to look simply terrible when exposed. This sort of construction is also known for leaving voids, and for poor bonding that leads to water infiltration over time. The water typically comes in through the centerline seams, which are rarely finished properly after joining, particularly on small production boats.

If you feel you can clean up the area in order to get solid, unshattered laminate as a base for your repair, there's no reason not to repair. You can also fill and/or glass over the centerline seams, again assuming that you can clean up the laminate sufficiently to allow for reasonable bonding.

I'd cut and grind back the material on one side of the rudder at a time, then clean up the steel reinforcement, and generally fair the interior with epoxy to prpovide a sufficiently smooth base for new exterior laminate. Then, laminate a new skin, using at least a 12:1 bevel to overlap the existing material on the sides. Repeat the process on the opposite side of the rudder as required.

[Rick]

Tim & Jason,
Thanks for resizing the photos and offering to assist in the future.

Tim - do you think I need to cut and grind the fiberglass skin off the entire rudder, or just the area where the cracks were? The glass is solid in other areas, but with the centerline cracks I have no idea what it looks like inside. I assume that the steel would be rusted throughout and who knows what the condition of the wood is. It is probably dry by now, since the boat has been out of the water for at least 8 years, and it's solid at the top of the rudder.

Also, if the fiberglass skin is solid, should I try to cut it off carefully to reuse it with its preformed shape, or try to recreate the shape with a new glass skin? That isn't an option where the cracks were located, as the skin broke up easily around the cracks. It was much more solid even several inches away from the cracks. I'm a rookie "fiberglasser" (I've been called worse!), so I'm concerned about replicating the shape of the rudder beyond the cracked area. Do you think some kind of foam would be an option for the inside of the rudder, or would that make it too light &/or to weak for this purpose.

BTW, it looks to me that the crack may have been caused by someone redrilling the holes where the rudder is held into its aluminum frame - which may have caused unusual stresses. I plan to epoxy the holes and reuse the original ones.

Thanks again for the help.

Rick

[Jason K]

If the wood in the deteriorated area is solid, then I would be real hesitant to open up the whole rudder. You may want to drill some pilot holes to get a feel for the condition in other areas. If the condition is reasonable, then I would repair just the damaged section and perhaps glass over the edges where the two halves come together.

[Tim]

I think opening the whole rudder is probably more work than it's worth. To me, anything much beyond repairing the area you've already opened up starts to cause diminishing returns on your labor versus the cost of a brand-new rudder.

The condition of other parts of the rudder are almost certainly similar to what you have exposed there, lacking any evidence to the contrary. From your description and the photos, I just don't see any reason to dig more deeply into the rudder. It is what it is, and a repair will be satisfactory. One need not reengineer the entire thing in this case.

I would look at the repair of the section you have opened as a good opportunity to hone your fiberglass and fairing skills a bit. You could use foam to recreate the shape in the void you've created, which would make it easier for you to laminate fiberglass over it in keeping with the shape of the surrounding areas.

The "filler" in the original rudder construction is there more to hold the two molded halves together than it is a t rue structural element. Foam-cored rudders are also very common. The real strength comes from the fiberglass skins. Foam has the advantage of being easier to shape, of course, than choppings or some epoxy filler. Frankly, I don't believe it matters that much what you use to shape the "inside" of the void, as long as you perform a structurally sound fiberglass repair over the top and properly tie it in with the surrounding areas.

Good luck!

[Rick]

Thanks Tim for the excellent and rapid response.

Rick

[Rick]

I've done some more work on the old rudder. I finished grinding down the cracked area I opened up. I also noticed some impact cracks in the blade of the rudder, so I ground the gel coat and found cracked glass underneath, so I ground that down also. Eventually, I decided that since I was going to glass the leading and trailing edges, I should also grind a few inches along those edges. A little grinding here - a little there - soon there was no more gel coat on one side of the rudder! Here's a pic



Then I repaired the holes and the cracked areas with glass and epoxy and a layer of epoxy thickened with West 406 filler.






Finally, I opened the splits on the leading and trailing edges of the blade and also filled them with the thickened epoxy. This left a nice round bead of epoxy on both edges that should provide some added protection. After getting rid of the amine blush (thanks Tim) I sanded all of the epoxy down with 60 grit paper.

Now I've got a new set of questions to complete the job. (BTW - It's less than 10 degrees out with an awful windchill, so I gave myself the night off!)

I want to wrap the blade and neck of the rudder in a couple of coats of glass, but don't know what the best technique is. Should I use some cloth tape along the leading and trailing edges first and then wrap large pieces of cloth around the blade, working my way up the rudder? Or should I first lay some long pieces of cloth the width of the neck of the rudder down to the blade to strengthen it and tie it into the blade? Also, should I butt the glass (weaker, but smoother) or overlap the glass wrappings?

After I finish the glassing, I've got 2 additional questions. First, in the first pic of the old rudder in my initial post, you can see the wooden insert in the top of the rudder. It needs to be replaced and I was wondering if anyone had a recommendation of what type of wood or other material would best handle the torque on the top of the rudder. Finally, what kind of paint do you recommend for the rudder?

Any and all suggestions are greatly appreciated. Thanks for the help.

Rick

[Hirilondë]

I want to wrap the blade and neck of the rudder in a couple of coats of glass,

Will the rudder still swing up inside the housing after you do this? You may have to use a slightly thicker stock for the spacer in the rudder housing (the piece of wood you are talking about).

You need a wood that is quite strong and holds fasteners well. There is a lot of stress on that piece. African mahogany would be a great choice, but still quite good and available at any local lumber yard is douglas fir

After you have determined that the repair is done, that is faired and sanded as well I would paint it with 4 or 5 coats of Interprotect 2000. This stuff can be hot recoated days after the previous coat. And bottom paint can be hot coated over it if within 9 hours. I hate sanding :)

[Tim]

...soon there was no more gel coat on one side of the rudder...

Have you also gone ahead and removed the gelcoat on the other side of the rudder too? You may as well do that now given your plans and the extent of the grinding you've already done.

I want to wrap the blade and neck of the rudder in a couple of coats of glass, but don't know what the best technique is. Should I use some cloth tape along the leading and trailing edges first and then wrap large pieces of cloth around the blade, working my way up the rudder? Or should I first lay some long pieces of cloth the width of the neck of the rudder down to the blade to strengthen it and tie it into the blade? Also, should I butt the glass (weaker, but smoother) or overlap the glass wrappings?

I would recommend applying long strips of glass over the leading and trailing edge, and then butting additional material inside the field to fill the remaining space. There's no reason to overlap your material; butt joints are the correct way to go here. If you want to tie the neck into the blade, then do so, but, as Dave mentioned, beware of any consequences of the additional material thickness with your rudder hardware.

Cut and lay out your material before you begin, so that you can fit the pieces together cleanly. Don't use overly thick or stiff material to wrap around those tight edges; you'll never get it to lay flat and remain air-free. I don't know what material you plan to use, but a couple lighter layers over the edges would work better than one heavier layer.

If you feel the need to apply more than one layer of material for whatever reason, then simply stagger the seams. But you don't need the weight, strength, or thickness of more than one layer of sheathing material. Remember that you already have a structural rudder; the additional material is only a sheathing to encapsulate your repairs and strengthen those areas.

You can either coat the repaired rudder with several coats of epoxy resin before painting, or use the Interprotect if you prefer. The end result is effectively the same, with the epoxy or epoxy-based barrier coat acting as a gelcoat replacement. Then paint the blade with bottom paint if your bottom is painted, and the top portion to match your topsides.

[Rachel]

I've read about this use in a few other places, but never asked much about it: I take it that Interprotect makes a good primer of sorts, even if you're not looking for it's stated barrier coating properties? What would be its closest non-barrier-coat equivalent - some kind of high-build primer? What does it do better (or the same as) other coatings in this type of application?

Thanks,

--- Rachel

[Rick]

Tim wrote

Have you also gone ahead and removed the gelcoat on the other side of the rudder too? You may as well do that now given your plans and the extent of the grinding you've already done.

I just ground the gelcoat along the edges on the other side, since I didn't find the same impact cracks there. Then I just lightly ground the rest of the gelcoat. I'll finish the grinding as you suggest to make it more uniform.

Dave wrote

Will the rudder still swing up inside the housing after you do this? You may have to use a slightly thicker stock for the spacer in the rudder housing (the piece of wood you are talking about).

The top of the rudder blade is still solid wood, so I can use that to keep the neck's previous thickness. Thanks for the heads up.

Dave wrote

African mahogany would be a great choice, but still quite good and available at any local lumber yard is douglas fir

Do I have to do anyting special with the douglas fir to keep it from splitting or having its grain rise over time? Would covering it with epoxy or Interprotect 2000 be sufficient?

Thanks again for the great info.

Rick

[Hirilondë]

Do I have to do anyting special with the douglas fir to keep it from splitting or having its grain rise over time? Would covering it with epoxy or Interprotect 2000 be sufficient?

There is really nothing that can keep a piece of wood from splitting, but it is quite unlikely it will. I would coat the piece with epoxy even if you use Interprotect later. West stands for wood epoxy saturation technique. One of its initial purposes was for just what you are doing.

[Rick]

I spent some time this afternoon looking for lumber to replace the wood in the top of my rudder. I went searching for a 2 x 8 piece of Douglas fir at several lumber yards and came up empty - it's a special order item. So, I drifted over to the local hardwood supplier and stumbled upon a great piece of 8/4 x 9 mahogany, as Dave suggested.

With the current rudder setup, most of the mahogany would be covered by the aluminum plates on the sides. A waste of a beautiful piece of wood. I'm trying to figure out how to keep more of it visible. Can I reduce the length of the aluminum plates or change them to stainless to allow more exposed wood? Or would I be compromising the strength of the rudder? Obviously, I no longer want to paint the wood. Do you think I should put on several coats of epoxy and then varnish it, or stick with the varnish alone. I read an earlier post of Tim's suggesting that the epoxy wasn't that effective under varnish. I was wondering if you felt the same about its use in this application.

Rick

[Hirilondë]

I don't think I would change the design of the rudder housing. Those aluminum plates take all of the strain of the rudder blade. Factor in also that it survived many years and even what-ever cracked the blade. I have a hard time ignoring stuff that works.

Epoxy is a great waterproofer. It builds up much faster than varnish. It has absolutely no UV protection and therefore must be over-coated with something (varnish, paint, etc). I like it in applications like yours because it is hard and will likely stand up better under the aluminum than varnish.

Cut, drill and dry fit the rudder housing using your new piece of wood. Then epoxy and varnish a couple coats or just varnish as you choose. Then assemble it again using some bedding (Sikaflex, Lifecaulk, 3M) between the aluminum pieces and the wood piece.

[Tim]

Can I reduce the length of the aluminum plates or change them to stainless to allow more exposed wood? Or would I be compromising the strength of the rudder?

From your pictures, I don't think you should reduce the size of the plates. They look like they need to be the size they currently are. There looks to be quite a bit of wood showing above the plate, which should satisfy your desire to show off that nice mahogany.

Maybe epoxy helps when it's applied under varnish, and maybe not. I have never seen a reason to do so. The varnish will need maintenance and upkeep no matter what, and if you keep up with that you're not going to extend the life of the wood if there's epoxy under the varnish. Or at least that's how I see it.

If you neglect the varnish and are counting on the epoxy to save the wood from the neglect of the finish, then it might help for a while, but we don't talk about neglect here, unless it's about reversing the effects of someone else's previous neglect! ;<)

In the end, there may be compelling reasons for either choice. I don't think there's really any proof one way or another; it;s all about how you happen to see the relative pros and cons.

[Rick]

I've got the glass work done on the kick-up rudder, except for some fairing and filling some hardware holes if I change them. Here are some pics of the final repair. Thanks again for the advice - this is my first fiberglass repair. It went OK - had some problems with dripping epoxy on the underside when glassing the edges of the board, but the PC grinder and some thickener took care of it.







I've prepared the mahogany piece for the top and now I'm planning to paint and attach the hardware on the rudder. I noticed that the setup on my rudder is different than what I've seen on other A21 sailboats. Here are some pics

My rudder's hardware setup:







Standard rudder hardware setup:



Mine attaches to the top of the leading part of the blade, while the other setups (all the other ones I've seen) attach to the trailing edge of the rudder blade. One advantage of my setup is that the line holding the blade down is centered and goes straight up through the pintles to the block near the tiller. I probably should add a block or something near the bottom pintle, since there is nothing there now.

Before I drill holes in the blade I'm trying to decide if one location is better than the other. I may just assemble the rudder and see if one method functions better, but that wont be very helpful without the bouyancy of salt water added to the equation. Any thoughts?

Thanks, Rick

[Tim]

See...a little fiberglass is nothing to be afraid of. Glad to see (and read) that your repair went successfully.

Have you used your rudder with its line setup the way you describe? If it works well, then I see no reason to change it. I guess the real question about usability with the lines on the leading or trailing edge of the rudder is which version is easier to operate and has a more fair lead when the rudder is placed in the down position. Certainly it's more important that the system works well to hold the rudder in its sailing position.

I might suggest leaving it as is for now, and only changing it to the other setup if you find a reason to. After all, you're old hat at this repair business now, so it'll be an easy change if you need to later.

[Hirilondë]

The rudder I just recently built for my dinghy pivots in the center. If it goes up and down as needed I would say it works, and see no reason to change. The strength comes from the overlap of the housing with the blade. Where you drill the hole doesn't effect it. If it ain't broke don't fix it.

[Rick]

The boat hasn't been in the water for almost a decade - and i just got it last year, so I don't know how well the current setup works. I've got a clean slate with the repaired board to install the hardware where ever is best. The reason I'm questioning the prior setup is that it's unlike those I've seen on other A21's. I don't know if it's an improvement or not, and i won't be able to tell until it's launched. I like the fact that my setup has the uphaul along the centerline of the rudder. It's the most fair lead, as Tim suggested. However, the line needs a sheave or block installed where the line enters the bottom pintle to keep it from wear. I'll follow your suggestions and use the current setup and see how it works.

I probably shouldn't admit it, but I enjoyed grinding, glassing and fairing the blade. Let's see how long that lasts when I turn to the hull, deck and interior!!

Rick

[Hirilondë]

probably shouldn't admit it, but I enjoyed grinding, glassing and fairing the blade. Let's see how long that lasts when I turn to the hull, deck and interior!!

That's cause you're one sick individual! But that's OK, your hull, deck or interior will cure you.

[Rick]

Here's a photo of the finished rudder so all who helped with sage advice can pat themselves on the back. Thanks again.

[Tim]

Looks good! Thanks for the update.