Fiberglass Rudder Shaft crack
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I have a vertical crack in my glass rudder shaft starting about 12in below the top and running up parallel through the bolt hole. Is this terminal? I figure the tiller head holds the top of shaft together and there isn’t a significant amount of force pulling the rudder down, so I don’t see the bolt pulling through the top of the shaft.
I was thinking of drilling some small holes perpendicular to the crack and screwing it together with epoxy.
Any thoughts or suggestions would be helpful.
Curt
It should be possible to repair your rudder post.
This is a problem with some of the stock rudderheads. They do not clamp firmly against the rudderpost. My own rudderhead cracked and I machined a replacement. Since then, I cut a pattern and have castings made to replace the Olson 30 rudderheads. I did this at considerable personal expense, thinking others would want effective rudderheads. This exercise was discouraging because I’ve had no inquiries.
The problem is that you have been turning your rudder using the throughbolt. That should not be done. The rudderhead should clamp tightly against the rudderpost. My new rudderhead is in two parts and I can precisely machine the 2″ hole so the rudderhead is firmly against the rudderpost and friction is transmitting the force to it.
Bolts are not intended to function in shear. They function in tension and hold things together. Rivets function in shear. That’s why bridge girders are held together with rivets.
That’s the difference between a bolt and a clevis pin. A clevis pin functions in shear. It’s the same problem. Don’t use bolts to replace clevis pins. Don’t use bolts to replace rivets.
I can provide a rudderhead that clamps firmly on your rudderpost.
That’s my two cents worth.
Al HoltAl,
I’d be interested to know how much you want for a new rudder head?Also What I have discovered is wear in the bearing surface areas. I even considered replacing my whole rudder. There must be a good method to resurface the bearing areas and still keep them true. Any ideas?
My post has worn at the lower bearing spot. To the point that even though the bearing is tight enough that it needs a a bit of lube to get it down the shaft, there is play at the bottom end. My solution for this was to wrap a few layers of teflon plumbing tape around the post at the worn area when ever I have the rudder out. It does not last the entire season, but it definitely helps!
I’ve never removed my rudder, but with all the talk about the glass shaft and bearings, I’m thinking of doing it for inspection/maintenance purposes.
Any science needed to do this operation beyond unbolting the head and dropping it? I have an elliptical.
Hi Bruce,
I just removed my rudder the other day. It is pretty simple, I did mine while in the water. I removed the tiller head (pain) and then used a 9 foot long pvc pipe that was laying around the marina to push the rudder down about 80 percent of the way (I lodged it agains my radar thingy). I jumped in the water, tied a rope around the rudder and ran it to a friend accross the way. I then pushed the rudder all the way through as my friend pulled on the rope. The rudder floats and it will want to jump out of the water, so to prevent it from the hitting the boat, your friend needs to pull on the rope so it stays away from the boat. I imagine it is a lot easier if you are on the hard, however I don’t think their is enough clearance to remove the rudder all the way.
Hadn’t thought about the shaft being too long to remove while on the trailer. I suppose I can back it over a cliff and drop it!
Bruce, beleive it or not, I would have not of thought of that. Could just back it up onto some ramps.
There’s a picture of my rudderhead and pricing at my website
http://www.holtmarinesystems.com
That price includes the anodizing, which I get done by professionals. If you want to do without anodizing or if you have a better source, you can take $75 off the price. I offer some other Olson 30 stuff there as well.
AlIf your boat is on a trailer, dropping the tongue down to the ground will give you enough height to remove the rudder. Just to be sure, measure the shaft plus the lenght of the rudder and make sure that total lenght is below the rudder and your good to go.
Now back to my shaft crack issue…
Curt…this split is a bigger problem than you think. First..the split should be epoxied/glued back together. That can be tough if the present epoxy/polyester crack gets a wax blush on it..new epoxy won’t stick! Injecting the crack could be a bad experiment.
You might need to ‘finish off’ the crack by breaking it open so you can clean it properly and re-epoxy the whole thing. Screws will hold the glue up, but you can’t squeeze out all the epoxy! That means the shaft will grow, but it is sandable. I’m NOT an expert at epoxy, but I have learned to not assume it will stick! Maybe a contact to West Systems for an idea of what to do? They can be helpful.
Curt,
A bit scary having a cracked rudder post. I’d cut the crack w/ a multi-tool, clean w/ paint thinner for wax removal then lacquer thinner, then vacuum bag w/ chop fiber and epoxy.Paint thinner? Not sure about that. Acetone maybe would be better. Let it dry.
Good approach to the repair, but I favor acetone, too.
AlThe reason for the paint thinner is to remove the wax. The acetone or lacquer thinner should remove any paint thinner residue.
Not sure, but to me paint thinner leaves a residue and another step. Acetone will remove wax.
Ya, to say the least I was pretty concerned about the crack myself. In the end I sanded about a 1/16 of the shaft and covered the top 8″ of the shaft with 2 layers of E-glass, overlapping the joints. It worked out pretty nice and my new bearings fit perfectly. In addition I shimmed the top with a slice of a Fosters beer can and now the tiller head fits very snuggly. All in all, I sure am glad I removed the rudder to check things out.
That said, I’m still interested in an elliptical rudder if anyone has one for sale.
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