Possible Rudder Rebuild Questions

[Northeaster]

Hi Folks,
Sorry for the long post.
Here's the story;

My timing is NOT the best, as I had the rudder completely off the boat last winter, as I rebuilt the pintle / gudgeon, on the skeg mounted rudder.
I did NOT rebuild the rudder last year, as I had drilled a few 1/4" test holes in the bottom, and got only a couple of drops of water from them, which dried up in a day or two.
Of course, I filled the holes with epoxy later, and added a couple of layers of epoxy & cloth, and then clear expoxy to seal it, before bottom painting it.

This year, my test holes dripped much more than last year! I am NOT talking about liters of watre coming out or anything, but is has been dripping slightly for a couple weeks, and is still damp underneath.

facts:
- Boat & rudder are 30 years old. I just bought it 2 years ago.
- used about 6 months/ year, as was on the hard during the New England winters, and now in Nova Scotia.

you can see pics of last year's rudder gudgeon repair here:
http://www.cruisersforum.com/gallery...p?i=4221&c=517

http://www.cruisersforum.com/gallery...p?i=4222&c=517

There are other pics, if you view all of my images!!

On the bright side, the boat is stored indoors again this winter, and there is a wood furnace, so I can work comfortably!

- I have noticed a very, very slight movement (have to really try to see it) between the rudder post, and the fiberglass, where the rudder post enters the top of the rudder. As the rudder post is connected to a steel frame inside the rudder, and then the foam / glass is overtop of that, I am not sure if this slight movement is normal, or signs of trouble.

The rudder is wheel steered - I replace the chain & wire last year, and it turns fine.

If there is any chance of rudder failure (ie from broken welds inside) then I would definitely repair it now.

I drilled one test hole (on an upward angle, towards the rudder post) a couple of inches below the top of the rudder, and it was completley dry!

If I choose to open up a section of the rudder, to inspect (and repair / beef up) the internal framework, I need to decide how much to open up.
- I could cut a section (approx 1 ft wide by 2 ft long) from one side of the rudder, that would allow me to see, and repair the internal framework.

I have a welder and the shop, so I can repair / fabricate some additional supports.

I do not want to weaken the rudder by cutting out to much, and not being able to do a great job of glassing over later, as it is still on the boat, and has limited room between the rudder and skeg.

I do NOT want to rmeove the rudder, as I did alot of owrk rebuilding / glassing over the gudgeon.

Any advice would be appreciated!!!

[AnchorageGuy]

With the boat being 30 years old and the fact that you can now open up the rudder and make repairs I would suggest that you do just that. Nothing is better than visual inspection and anything else is speculation. Removing a panel on the side will give you access to inspect and do repairs if required. Re-glassing the panel back is fairly easy and most of this can be done with the rudder still on the boat. And if nothing else it will give you piece of mind. So the question becomes, why wouldn't you open it up? Good luck.

[Northeaster]

Hi Chuck,

Thanks for the advice!!

The only reason I would not open it up, is if I thought that I would make it weaker by doing so. I realize that if it is repaired correctly, that would not be the case. However, let's say;

I remove too large of a panel on one side (or split is down the middle, which would be much harder to repair, due to the proximity of the skeg).
Now the repaired, and very strong internal framework will exert alot of pressure on each side, as the rudder is turned. If the epoxy / cloth used to reattach the cut out area ( or two havles, if split down the middle) is not sufficiently thick/ strong/ well bonded, the pressure of the internal framework could casue the repair to fail.

If the rudder was off the boat it would be easier to reglass / cloth it later. I want to choose a method of repait that is easier to repair, while on the boat, yet still gives me lots of reair strength.

I am thinking, for example, of removing ony a 1 ft wide strip, or maybe less, as that woudl allow me access to weld / replace the framework, yet still leaving the ends of the framework to be covered by the original, and thicker sides of the rudder. Some force would be exerted on the repaired area, but much on the untouched surface as well.

Just trying to see what my options are!!

[Stevens 47]

I have noticed a very, very slight movement (have to really try to see it) between the rudder post, and the fiberglass, where the rudder post enters the top of the rudder. As the rudder post is connected to a steel frame inside the rudder, and then the foam / glass is overtop of that, I am not sure if this slight movement is normal, or signs of trouble.Thats the part that would worry me the most, as it may be where the water is coming from. It will be hard to affect a repair that will stand the test of time with it in the boat. I suspect that once you start removing panels you will find that you will have to keep going. You may address the corrosion issues with the metal parts in the rudder and you will still need to address the water egress.

[Northeaster]

Stevens - I agree with you about the possible water entry at the top. However, when i test drilled a couple of inches below that point, I was happy not to find water running out. However, I guess that any water that entered there woudl have quickly flowed to the bottom of the rudder, and left the top dry - once out of the water.

I am definitely concerned about making it watertight after any repairs. With the rudder on the boat, it would be harder. However, it still would be managable, I think, to wrap the entire rudder in overlapping cloth/epoxy layers, after 1st adding additional cloth/epoxy to the repaired area. By turning the rudder hard one way, and then the other, there is enough access between the skeg, and the leading edge of the rudder to get cloth and epoxy laid on there.

I would, of course, sand off all bottom paint, until I get down to a fiberglass surface before starting this.

[AnchorageGuy]

I still would open the rudder up. You are correct in only opening up what you need to to inspect and open more if you need to repair. A proper re-glassing should not fail since forces on the outside of the rudder are pushing in against the internal framework and if they aregreat enough to destroy a good repair you will probably loose the rudder no matter what.

[svHyLyte]

There should be no movement of the rudder blade with respect to the post. They should be a single solid unit. If you can move the blade independantly of the post the bond between the core and the armature--the metal framework attached to the post within the blade--has begun to break down. Water intrusion here will eventually cause the armature/post connection to fail.

We had a similar situation. On our boat we were able to cut throught the skin of the rudder on one side, near the edges of the blade, and remove it intact to expose the core. With this we removed the old wet, deteriorated foam--dried and blasted rust and corrosion off the armature, welded up reinforcing bars to the armature/post, coated all with epoxy, and had new high density foam injected by Foss Foam. We then used the side that had been removed to shape the exposed foam and reinstalled the cutout with epoxy, after which the entire rudder was reglassed and painted. The problem was caused by a poor bond between the original glass and the rudder post on the top of the rudder which eventually failed and allowed water to intrude. Epoxy coating the post allowed for a much better bond between the new glass and the post although this connection is now futher sealed with a coating of 3M 4200.

The work was done in January, 2002, by Snead Island Boat Works of Palmetto, Florida, and, Foss Foam as noted, and all-up came in at about $2,900 for a First 42.

FWIW...

s/v HyLyte

[imagine2frolic]

It's not fully broken yet, but it will, and it always happens at the most inconvenient time. Will you trust your family's life to a possible rudder failure? Pull apart a small area, and then continue on as needed. Once it's apart it won't make any difference the amount of time for a small repair, or one whole side.

I found a small blister oozing water on one of my rudders. I opened it up, and found water. I had to keep making the hole larger, and finally just cut away at least half. I could see everything plainly, and let it dry. Flushed it out, and let it dry again. Filled the area with foam, and the next day took a hand saw, and cutaway the excess. I faired it, and skinned it. It took a couple of hours a day over 3 days. Drying the rudder was the cause of the 3 days........BEST WISHES in it being a simple fix.....i2f

[jrd22]

Like HyLite, we opened one side of our rudder and removed all the old saturated foam. We dropped the rudder a little bit so we could use a die grinder to grind out around where the post goes in the rudder and resealed it with 5200. Unfortunately, it sounds like you will have to drop yours to seal this area. Pretty easy to just cut the side off and then re-glas it when done. Good luck.

John

[Northeaster]

Thanks guys!!! for all of the hands-on experienced details.

I will open it up soon, and see what I find. I will start with a small section, maybe 6" wide by 12" long. That should allow me to see the welds on the top and middle parts of the internal framework. Then if necessary, I will keep moving down to the bottom. As mentioned, once it is opened up, a larger section is not much harder to repair than a smaller one. I have gained a fair bit of epoxy experience last year, on other projects.

Re: dropping the rudder - I have about 1 1/2" of access between the rudder top and the bottom of the hull, so I think I will be able to work on / seal the top of the rudder without dropping it. If necessary though, I can drop it and redo the skeg / gugeon repair.

[Northeaster]

UPDATE!!!!!

1st of all, thanks for the input so far! I do believe that opening it up was the correct thing to do, based on not knowing the condition inside.

However, unfortunately there was nothing wrong with the structural integrity of the internal framework to rudder post in the least. Perhaps the original construction method varied form normal, but i was not able to "simply" cut out and remove a section of "skin" on one side, as there was a large amount of solid glass, that covered the internal framework and internal rudder post.

There was no chance of water deteriorating the welds or internal framework, as most of it was covered in inches of solid glass.

I kept cutting deeper, to try to detach the section of skin (but was cutting into 2" thick glass along the entire area where the welds would be).

In the end, I have substantially weakened the rudder, by cutting into, and removing, all of this solid glass, that had encased the rudder post and internal framework.

Now that I have it opened up, I will beef it up (mostly to offset the weakening that i have caused), by welding a large flat SS plate along the rudder post, in between the internal framework - to make it stronger than before.

Then, instead of using foam, which will not replace the strength of the now cut solid glass, I will fill the void with some mixture of epoxy and chopped glass & cloth (or thickened epoxy). I definitely want the void between the 2 skins to be bonded to the skins, by the eppoxy mixture.

I could just glass up the opened rudder skin, and inject epoxy from a hole in the top. However, I woudl not be able to see how it settles in there, and am not sure how the several inch void would react as the heat from all that epoxy is given off. I guess that I could wrap a bunch of cloth in there before closing up the side, so that the injected / poured epoxy could saturate the cloth, fill the voids, and bond to the outside skins.

Otherwise, I may just build up the internbal area, a few inches at a time, by using a plate over the large opening, to keep the epoxy inside, and form the outside skin. This way I could do a few inches at a time, which woudl not give off as much heat, when curing. As long as I kept mixing the next batch, before the last one hardened, I could work my way up to the top of the rudder, before finally filling the top of the void.

Either way, i want to make sure that I use epoxy (and some cloth, etc) to add the same type of strength that was already therem in the solid glass sections.

Any advice woudl be appreciated!!

[AnchorageGuy]

I think your best course of action is to rebuild the removed glass with cloth and resin. Filling the cavity with epoxy will not make it stronger. Epoxy by itself is very brittle and not all that strong.

[Northeaster]

Yes, I do want to do more than just poor in epoxy resin. I realize it is not strong on it's own.
If the rudder was off the boat, I could lay it flat, and then lay-up epoxy resin and lots of cloth / mat, etc, without worrying about gravity being my enemy.

However, to rmeove the rudder would mean removing the gudgeon, from the skeg (which I repaired quite sturdily last year). Then I would have to re-epoxy / cloth it, which is also vertical, so I would be no further ahead.

I am confident I can repair the rudder well, while on the boat. I just ahve to work in such a way that keeps gravity form pulling all of the cloth and resin down.
The area to be filled with resin (and lots of cloth ,mat, etc) is about 8" wide, 3" deep, and 18" high.
Just wondering how many cubic inches of resin (and cloth) can be filled at one time, without generating too much heat, and problems.

For example, if I broke the sections up into three 6" high sections, each 8" wide x 3" deep - Could I fill each of those separately, in 3 batches of resin that would be mixed as the one before was kicking, and not fully cured. I would not simply fill with resin, but would have substantial amounts of cloth mixed with the resin, to fill the void.

I would using something like a flexible plastic cutting board, which I would clamp to the rudder, to hold the profile of the missing skin. I would then move it up to the next level, as the 1st level kicked, so that I could then pour in the next resin batch, and more cloth, as I work my way to the top.

This would still be 144 cubic inches of resin / cloth at a time, which may creates alot / too much heat.

Any thoughts on the nest way to lay it up the voids, without having gravity bring it down, woudl be appreciated!!

[Stevens 47]

I have done allot of overhead and vertical lamination. Size of the repair is not really a consideration unless it is enormous. For your rudder repair the size should easily fall within the scope.

What I do is to roll a tack coat on first, it is timed. Say the epoxy resin you are working with has a rated 30 minute gel time, as you batch the tack coat set your timer for 60 minutes. When the timer goes roll on your cloth, the surface will be really sticky. In a vertical application start from the top and roll the cloth down using a roller to flatten and stick the cloth to the tack coat, make sure the upper most edge is well stuck down because if not gravity will get hold of it. Next wet out the dry stuck on cloth with the roller resetting your timer for another 60 minuted sequence you can use a hard roller to roll out any air bubbles. Keep repeating until you have your part built. You can do this for as many layer that you can do in a day. Roll on peel ply at the end of the day if you want to begin laminating again with out sanding the next day. You will have a chemical bond. I always pre-cut all of my cloth prior to starting. Use a piece of clear plastic to make a cloth lamination pattern. Lay this over the ground out repair, tracing the cloth you can keep tracing a reducing pattern on the plastic to to cut your cloth too. You of course will scarf the lamination into a 12-1 schedule.

[Northeaster]

Stevens - Thanks for the great tips! I wish I had been more patient, and waited till my mixtures thickened up, when I tackled the vertical skeg gudgeon work last winter. Gravity made me watch it closely as it tried hard to slide the cloth out of position, before finally kicking.

I do see your method as being very useful, when laying up something like a 1/4" to 1/2" thick layer of epoxy resin and cloth.
However, in my case, I need to fill a void 3" thick!! If I just keep wetting and laying layers of cloth, they probably only add 1/16" each time, for example. Perhaps I am missing something!!
Can you be more specific, as to the cloth / mat materials that could be used to achieve "thicker" layers, and therefore fill the 3" thick void faster, yet, with full strength. I could add thickeners like collidal silica, etc, but do not think that they would give me the strength that layers of cloth would. Perhaps, lay several layer of cloth, then fill the big void with thickened epoxy, then more layers of wet cloth, or something like that??