Bent Rudder Shaft
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I have spent some time thinking about this issue regarding my C36. Mine's not bent, but I was wondering how one might remove, repair and replace the rudder while at sea. The rudder post "tube" that is glassed into the boat is what keeps the water out. If the post is bent, you should carefully check the tube for cracks or other damage, as you could sink the boat if it breaks free. I think that if you remove the rudder post head you could push the rudder out the bottom of the boat. The rudder is probably very buoyant, so it will be a little hard to push down, but once out, should pop to the surface. If I'm wrong about that, it might sink. In any event, it might be a good idea to have a tether attached. My idea as to a process was to make a plug for the rudder post that would secure a tether. Once the rudder was pushed out, this tether would be the messenger for pulling the new or repaired rudder back in. The idea is that you'd have both ends of the line in the boat, one going over the side and up into the rudder tube, the other coming out of the tube. The repaired rudder could be temporarily ballasted so you could sink it and then pull it up into the tube using the messenger. The ballast could be tied with a hitch that can be slipped once the rudder is in, and then the ballast recovered on board. Good luck.
I have spent some time thinking about this issue regarding my C36. Mine's not bent, but I was wondering how one might remove, repair and replace the rudder while at sea. The rudder post "tube" that is glassed into the boat is what keeps the water out. If the post is bent, you should carefully check the tube for cracks or other damage, as you could sink the boat if it breaks free. I think that if you remove the rudder post head you could push the rudder out the bottom of the boat. The rudder is probably very buoyant, so it will be a little hard to push down, but once out, should pop to the surface. If I'm wrong about that, it might sink. In any event, it might be a good idea to have a tether attached. My idea as to a process was to make a plug for the rudder post that would secure a tether. Once the rudder was pushed out, this tether would be the messenger for pulling the new or repaired rudder back in. The idea is that you'd have both ends of the line in the boat, one going over the side and up into the rudder tube, the other coming out of the tube. The repaired rudder could be temporarily ballasted so you could sink it and then pull it up into the tube using the messenger. The ballast could be tied with a hitch that can be slipped once the rudder is in, and then the ballast recovered on board. Good luck.
Doubtful wisdom.
You must remove the rudder to repair it. This can be done in the water, but it is risky. If you should drop the rudder, which is easy to do, you may never recover it if there are any currents. They are often semi-bouyant and can drift for a long, long distance. Had this happen to a friend. You also have a hole in hull that is difficult to seal and puts you at risk if the top of the rudder tube should become lower than the water level for any reason. Heard about one sinking when the scuppers got stopped up in the rain and the cockpit filled. Repair of a bent rudder shaft requires a skilled metalworker and is accomplished by cutting off the rudder post at the bend. Open the kink caused by bending by using a hydraulic porta-power tool. Chamfer the edges of the newly rounded stainless tube by grinding. Insert a proper sized stainless pipe sleeve. Weld it all back together. Grind and polish the welds flush. Reseal the top of the rudder with 3M 5200. Reinstall If you have to hire out all the metalwork and buy the sleeve, you may find it cheaper to order a new rudder from Catalina. If you try to bend the rudder post straight, it won't be round, won't fit back in the tube and will be substantially weakend. A subsequent bending could likely result in a break and loss fo rudder and steering. With average luck, that will occur at the worst possible time. Regards,
You must remove the rudder to repair it. This can be done in the water, but it is risky. If you should drop the rudder, which is easy to do, you may never recover it if there are any currents. They are often semi-bouyant and can drift for a long, long distance. Had this happen to a friend. You also have a hole in hull that is difficult to seal and puts you at risk if the top of the rudder tube should become lower than the water level for any reason. Heard about one sinking when the scuppers got stopped up in the rain and the cockpit filled. Repair of a bent rudder shaft requires a skilled metalworker and is accomplished by cutting off the rudder post at the bend. Open the kink caused by bending by using a hydraulic porta-power tool. Chamfer the edges of the newly rounded stainless tube by grinding. Insert a proper sized stainless pipe sleeve. Weld it all back together. Grind and polish the welds flush. Reseal the top of the rudder with 3M 5200. Reinstall If you have to hire out all the metalwork and buy the sleeve, you may find it cheaper to order a new rudder from Catalina. If you try to bend the rudder post straight, it won't be round, won't fit back in the tube and will be substantially weakend. A subsequent bending could likely result in a break and loss fo rudder and steering. With average luck, that will occur at the worst possible time. Regards,
That depends!
It really depends on how badly bent the post is. I would say that if it is bent but not kinked, it could be straightened out without suffering in strength. It should be examined closely, with a magnifier, for cracks. In fact, stainless steel, along carbon steel, actually increases in strength with "working." Welding could be chancy if you don't know what series stainless it is. Catalina might be able to tell you. The heat involved might damage the fiberglass rudder. The biggest threat with these rudders seems to be crevice corrosion due to oxygen starvation of the post inside the rudder and, of course, bending them. I'd try to bend it back if it isn't kinked, and replace the entire rudder if it is.
It really depends on how badly bent the post is. I would say that if it is bent but not kinked, it could be straightened out without suffering in strength. It should be examined closely, with a magnifier, for cracks. In fact, stainless steel, along carbon steel, actually increases in strength with "working." Welding could be chancy if you don't know what series stainless it is. Catalina might be able to tell you. The heat involved might damage the fiberglass rudder. The biggest threat with these rudders seems to be crevice corrosion due to oxygen starvation of the post inside the rudder and, of course, bending them. I'd try to bend it back if it isn't kinked, and replace the entire rudder if it is.
Discussion.
Having just been through this with our C320, I'll add a couple of non-theoretical observations. First...If there is any new friction while turning the wheel/tiller...your shaft is kinked...no 'maybe' about it. Second point...work hardening changes the characteristics and does not make metal 'stronger' per se. While it does get stiffer and doggone hard to drill, it also gets more brittle. The result is that it doesn't bend as easily and will take more force to deflect than before, but when it is forced enough to give, it will more likely break. Third point...I discussed the repair process with Frank Butler at Catalina personally...so no guessing as to Catalina's opinion. I don't recall whether it is either 316 or 304, but a phone call to Catalina will clear that up pretty quick. Yes, heat near FRP can be a problem, but an expert welder can deal with it. Last comment...I decided on the replacement rudder even though it came out of my pocket..simply to eliminate worries and because I could get a replacement faster and only a little more expensive than the fix. On the other hand, when I get around to fixing the old one. I'm sure I'll have a solid spare.
Having just been through this with our C320, I'll add a couple of non-theoretical observations. First...If there is any new friction while turning the wheel/tiller...your shaft is kinked...no 'maybe' about it. Second point...work hardening changes the characteristics and does not make metal 'stronger' per se. While it does get stiffer and doggone hard to drill, it also gets more brittle. The result is that it doesn't bend as easily and will take more force to deflect than before, but when it is forced enough to give, it will more likely break. Third point...I discussed the repair process with Frank Butler at Catalina personally...so no guessing as to Catalina's opinion. I don't recall whether it is either 316 or 304, but a phone call to Catalina will clear that up pretty quick. Yes, heat near FRP can be a problem, but an expert welder can deal with it. Last comment...I decided on the replacement rudder even though it came out of my pocket..simply to eliminate worries and because I could get a replacement faster and only a little more expensive than the fix. On the other hand, when I get around to fixing the old one. I'm sure I'll have a solid spare.
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