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I keep reading scary stories of older fiberglass boats having their rudder’s fail because the rudder stock is made of stainless steel, which we all know can have serious corrosion problems in saltwater.
Rainshadow’s PO said he knew the rudder was taking on water, so he had it “reglassed” (not rebuilt). Later, the pre-purchase survey said the rudder has moisture in it. This makes me wonder if we should do some exploratory rudder surgury before we take Rainshadow on serious blue water journeys.
Has anyone had their rudder fail, or require any major repairs?
I do have the Nic 38 CD that Jeremy Lines prepared, and it includes a useful drawing of the rudder details. Also, the Handbook says this:
“A steel muff coupling is fitted to the rudder stock to allow easy withdrawal of the rudder. To remove the rudder, the heel fitting and steady band must be removed. These are secured with stainless steel machine screws tapped into the GRP and locked with Pregel. The rudder is moulded around the stock so the latter is not removeable.”I believe the PO said he couldn’t get that steel muff coupling off, so the marine mechanic cut the rudder stock, and then welded it back together. Since I have never seen evidence of this weld, I begin to wonder if my memory is correct…
The rudder on Voltair was a writeoff during our catastrophe in Scotland in winter 2000/1. It was rebuilt for us by Baltic Wharf boatyard who did the repairs in Totnes, Devon, and I don’t remember seeing the ?bronze? structural member around which the new glass was laid up, before it was laid up. However the guy who owned the boat before us did have experience of “dropping” the rudder out – he said it was the most terrible job and that you need a lot of height to do it! I think ours is split with a coupling, which you can see through the door in the aft cabin.
I haven’t done anything to my rudder but wonder how the bronze rudder stock is attached to the fiberglass blade. I’d rather not do any “exploratory surgery” if anyone has info on this.
Fred “Oasis” hull #99
The rudder on Rhapsode was removed by a boatyard in 2004 (in the south of France) when the boat was undergoing treatment for osmosis.I was not present at the time but the yard made no mention of any particular difficulties except that they lost the lower bronze bearing(The yard went bust and a year later the bearing was found tucked away in the lazarette). I am quite certain that the rudder stock was not cut. Before the new yard reattached the rudder they added a layer or so of grp matting and expoxied the whole thing. No problems since.
Chihili Q’s previous owner had the rudder rebuilt but I’m afraid I have no details; he said at some point there was a bit of play between stock and GRP blade. It seems sound now but hangs to starboard within the steady band (whose name I didn’t know previously!).
Hello to all, new member Charles from s/v Rampant #53.
We are having our rudder rebuilt now in Deale, MD. There was some movement of the rudder from the shaft and it was putting stress on the rudder port. We had it cut open and had an additional bar added to the internal metal structure to strengthen it. Hopefully it will be better than new!
Hi Charles – How did you detect the movement? We will be hauling Rainshadow in about a month, and I’m trying to discover what to look for before any problem becomes so serious that it might lead to failure. When sailing in a good wind, we can get a vibration when turning the helm, but that seems to be coming from the mathway steering bearings rather than the rudder itself, because the vibration frequency seems too high to be coming from the rudder in water.
When your rudder was cut open, was there any evidence of crevice corrosion of the stainless rudder stock? Do you have any photos of what you found?
The Nic 38 CD that Jeremy Lines put together includes a rudder drawing, so I have some idea what’s inside.
Hello Marilyn, thanks for your patience. I will need to learn how to upload, etc. The rudder work is being done remotely so I haven’t had hands on. But here is the report I received when first digging into the issue. Hope this helps! Charles
o The rudder itself appears to have some structural issues as the body of the rudder moves free of the structural internal armature. We will need to inspect this once the rudder is off the boat, but it looks like some work will be required there.
o The lower rudder shoe has a significantly worn bushing. (photo 7, 8 and 9). This is part of why the rudder port has been leaking so badly over the years. Excess play in the rudder bearings places unacceptable loads on the rudder port making it act as a load carrying bearing. This installation will need to be corrected during installation.
o The middle gudgeon was completely corroded and de-zincified. (pictures 3, 4, 5, 6) The bright red metal visible in the breaks indicate the extent of de-zincification that occurred. This component obviously needs to be replaced.
o The rudder shaft coupling was corroded and seized to the shaft and had to be cut away in order to free the rudder for removal. This will need to be replaced during installation.
o The steering linkage that connects the gear box to the tiller arm is completely frozen and corroded. (photo 10) This will need to be replaced during installation. The rest of the steering mechanism will be cleaned and inspected and serviced as appropriate. Any further damaged parts will be brought to your attention as that work progresses.Charles also sent me the photo of Rampant’s rudder cut open – this must be the top portion of the rudder, since it shows the metal support inside that is positioned above and aft of the aperature. Again, see drawing 65 of the Nic 38 CD to understand this.
In response to a question from Marilyn, we had to get work done on our mizzen mast step. The fiberglass under the mizzen mast had given way and we had to have it reconstructed and reinforced. There was also corrosion on the end of the mast and we had to have it cut off (about 1″) and a plinth built for it to retain the same height. I will post a more complete overview of all we are having done to Rampant.
Hello all. I too have to do some work on my rudder. Does anyone know the orientation of the photo of the disected rudder? Can anyone tell me if the rudder was of solid construction and what materials were used? My rudder is a different shape to that shown on drawing 65, the top is more square and clears the bottom of the hull by about 20mm. Many thanks, Pat, Sea Thrift of Rame.
I’m as curious as Pat is – we’re planning to disect our rudder next year, and we’d love to learn from those folks who had already had to do this job. We talked to a shipwright today, and he is suggesting that 1) we cut open the side, 2) dig out all foam etc (or whatever is in there), 3) replace the metal parts, and 4) prep it for epoxy infusing new foam and adding a new skin on the disected side. This shipwright loves to do epoxy infusions, though he says he’s never done it on a rudder before. We’re worried that such a repair would mean it is impossible to ever disect the rudder again to replace the metal parts when required in the future, as the rudder will essentially become a solid foam/epoxy structure with the metal armature + post buried inside.
For those of you who have already tackled this rudder repair – how did you do it?
Cheers – marilyn
Apologies for the lack of postings. “Nutmeg” is having her rudder done at the moment, a job I’d wanted to have done since I’d bought the boat, but never got to the top of the list! There has always been a little movement between stock and blade but despite worrying about it over 2 Transats we’ve had no issues whatsoever. However I knew it had water inside. I will post some photos once I’ve seen what it all looks like.
It was a real pain to get out as the mild steel sleeve which joins the stock together was absolutely solid and needed to be cut off. Then the prop and shaft needed to come out, and the boat lifted off its cradle to get the rudder off – all good fun…
We are again thinking seriously about doing this rudder job – having avoided it until now. We are worried because there is a very small amount of play between fiberglass and lower stock – and we are worried about internal corrosion as the rudder leaks.
Ollie (or any one else who has done this) – any words of wisdom? Specifically:
1) The rudder dwg says the lower stock is Manganese Bronze, not SS. Is this true? If so, then maybe the metal won’t be corroded nor require replacement?
2) Was the foam interior core water saturated? If yes, what did you replace it with?
3) Does it work to cut an access hole in one side of the rudder to do repairs and then glass it back closed? Or would it be better to make a mold of the original rudder and build a whole new one?
4) Did repairing your rudder actually eliminate the slight movement between fiberglass and stock? Do the torsional forces on the stock cause it to flex and so the rigid fiberglass delaminates from the stock? In other words, is this small flexing a problem beyond allowing water into the rudder core? If flexing is not a problem, then it seems a suitable repair is to make a flexible collar between stock and fiberglass to absorb the motion and seal the water out.
5) If the main goal of the repair is to replace a saturated foam core and make a post-to-fiberglass collar seal, couldn’t this be done without removing the rudder?
6) Has anyone besides Rampant’s owner Charles had the gudgeon be dizincified and require replacing?
Thanks in advance for any replies.
marilyn and VanI had the same problem with Sea Thrifts rudder. The stock was loose in the blade and there was a split near where the shaft entered
The repair was done by drying the boat out on a local slipway between spring tides which gave us a few days to complete the repair. A plastic awning was rigged to protect the job from rain the weather was far from perfect.
The tiller arm and shaft joining collar were detached inside the boat and the rudder support band and pintle shoe where removed.
We were then able to drop the rudder an inch or so to help access.
The rudder starboard side was the ground out to follow the rudder tang. The width of the grinding track about 6 inches. The rudder shaft was found to be bronze and in good condition.
The condition of the rudder filler was better than expected and using a moisture meter we found the concentration of moisture was around the upper third of the rudder
The rudder was dried for a day using two hot air paint guns on stands the repair was then carried out using epoxy resin and bi axial cloth. Large clamps were needed to hold the tang firmly in place as work proceeded. A lot of epoxy and cloth were used and the repair was very strong. I suspect stronger than original as the front of the rudder was now solid epoxy and bi ax.
The bottom pintle was broken so we turned a new one using a scrap of bronze. After a year all is perfect. Hope this helps.PatHi Marilyn
I haven’t had to rebuild Orion’s rudder…yet. But I have built several race boat rudders. A particularly challenging one, was a teardrop shape, that had to accommodate a 4″ rudder stock. If I were you, I would make a mold, and start from scratch. There are so many more advanced materials available these days. A completely new construction avoids having to match 40 yr old technology. I went down below and looked at the rudder, today. It appears to be a straight line taper, from the stock, to the trailing edge. That would be an easy mold, to make.
I was recently in your neck o the woods, Anacortes and visited the shop that built Ellison’s tri-maran. You should see how they build the centerboards, that the current 70′ cats, are hydroplaning on top of!! The material strengths are mind-boggling!
Good luck with that repair. I have to find out more about the Nic 38’s lower rudder bearing, so I can pre -make a replacement before I haul Orion, in the spring.
michael
OrionWe finished our rudder rebuild and you can read about it here.
Summary: we had a stainless steel rudder stock that showed signs of crevice corrosion, so we replaced it with an Aluminum Nickel Bronze one. Replaced all the foam, and rebuilt the body of the rudder. We also replaced the mild steel collar with a coupler custom built for us by Port Townsend Foundry.
Feel free to contact me if you have any questions. (See password protected member directory for my email address).
Van
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