Rudder Stock Failure

[HappyMdRSailor]

Originally Posted by Guy

A piece of solid rod/shaft as long as you can make it will be stronger than the old piece of tubing. Heavy though. Cut away enough composite to make lots of rosette welds as well as the butt weld of the old tube. Should be good to go. Better than being stuck somewhere unable to build a new rudder. It would need to be shortened to get rid of the bad material which might be a problem.

A solid piece of rod the ID of the tube shaft WILL NOT be stronger than the original tube stock... Moment strength in X-Y-Z are proportional to the 4th in radius...

[SVTatia]

If you decide to jury-rig the rudder keep in mind that the shaft inside the rudder is prolly in much worse shape than what you see outside, and may not be able to hold anything for too long.

[crazyoldboatguy]

Bolt it - don't weld it. If the stock has this level of corrosion anywhere else, the weld will likely not hold. 1/2" bolts may seem like overkill but you are looking for surface area on the suspect rudder stock. If you can get 18" into the part above and below the fail point, all the better. You must have at least 3 bolts above and below for 6 total. Carefully choose your transit time making sure you are not going to encounter and wind or waves. Do not sail - power only. Make sure your EPIRB is fully charged with a new battery and your abandon ship bag has fresh water in it.

[HappyMdRSailor]

Originally Posted by SVTatia

If you decide to jury-rig the rudder keep in mind that the shaft inside the rudder is prolly in much worse shape than what you see outside, and may not be able to hold anything for too long.

+1

Originally Posted by crazyoldboatguy

Bolt it - don't weld it. If the stock has this level of corrosion anywhere else, the weld will likely not hold. 1/2" bolts may seem like overkill but you are looking for surface area on the suspect rudder stock. If you can get 18" into the part above and below the fail point, all the better. You must have at least 3 bolts above and below for 6 total. Carefully choose your transit time making sure you are not going to encounter and wind or waves. Do not sail - power only. Make sure your EPIRB is fully charged with a new battery and your abandon ship bag has fresh water in it.

+2

[rognvald]

Stara,
Your rudder is obviously saturated from the pix--undoubtedly a contributory factor to the shaft failure. Nothing short of replacement or rebuild will work. Was your shaft bonded to the electrical system in your boat? Is it aluminum or stainless? Who is the manufacturer of the boat? Are you willing to gamble your life and/or vessel for a quick fix? Great pix. Thanks for sharing.

[nimblemotors]

Bolting it is the best method, but please tell me how you drill 1/2in holes in a hard stainless steel shaft on boondock island.

You can just do as the welder suggests, put in a solid shaft, grind away the bad metal and weld it in,
and then don't put any stress on it as much as possible to get where you can replace it, use the engine which should not stress a rudder.

Get two outboards mounted on the left and right side to steer with them
when the rudder fails.

[Travelnik]

Glue it with 5200. Problem solved!

[HappyMdRSailor]

Originally Posted by nimblemotors

Bolting it is the best method, but please tell me how you drill 1/2in holes in a hard stainless steel shaft on boondock island.

You can just do as the welder suggests, put in a solid shaft, grind away the bad metal and weld it in,
and then don't put any stress on it as much as possible to get where you can replace it, use the engine which should not stress a rudder.

Get two outboards mounted on the left and right side to steer with them
when the rudder fails.

[crazyoldboatguy]

Ah, machining SS. Been there many times. It looks like the shaft has been pulled from the boat. A drill press could be used - that would make drilling much easier. I would drill a pilot hole of 1/8" so as to relieve some of the stress on the 1/2" drill point. You might need 1 drill bit for each hole unless a sharpener is nearby. You don't need SS for the inner/jury shaft - hell, it could even be just heavy schedule pipe but solid would be best. I cut thread on dozens of 3/8" SS rod (don't ask) and we used cutting fluid and ice chips. The dies lasted 10 times as long when we kept the temp down and were liberal with the cutting fluid. Keep the drill speed as low as possible and maintain even pressure on the bit.

[Cheechako]

A piece of close fitting welded bar inside should get you 100nm easy. he needs a good weld. Then get it done right replacing the whole shaft.. and don't try to save weight with a tube shaft... go solid.

[model 10]

Originally Posted by HappyMdRSailor

A solid piece of rod the ID of the tube shaft WILL NOT be stronger than the original tube stock... Moment strength in X-Y-Z are proportional to the 4th in radius...

Remember, this is not a bending moment but a torsion bar. Drilling a solid 1.5" bar is a big deal. Weld it.

[Ex-Calif]

Cruising = Fixing boats in exotic locations.

Aside from the admonishment - This rudder has been sending you signals, why didn't you see this at haul out/inspection?

I am with the internal sleeve, bolted w/backup plan.

It also depends on what is the 100nm I want to cross. Is it 100nm up a coast or is it 100nm across the Tasman in winter?

100nm is arguably a 24 hour sail/motor sail.

Aside from the obvious problem of drilling SS I would vote against welding because you don't know the condition of the underlying shaft and the weld can break immediately and opening holes to access for welding creates other issues.

OTOH - 100nm at sea is way different than 100nm by car. Presuming I could drive the rudder out of there I could take it for a rebuild or get a new one. I may be assuming but is the issue one of cost of boat storage where the boat lies?

If so it is not a sound decision making criteria. The only criteria should be - quality/durability/suitability of the repair for the intended "emergency" travel planned.

We used to say in aviation, "It's better to be down here wishing I was up there than to be up there wishing I was down here."

Substitute "on-shore" and "out there" for boating...

[jimbunyard]

To repair that rudder for full service will cost more than a new rudder. Sure, you could weld a stub inside, and it might even last a while. That looks like a 2 1/2" tube, so the inner stub would be 1 1/2", pretty strong, but remember you're going to lose about at least 2-3" cutting the tube back to weldable metal. Providing the tube inside the rudder is not rotted even further down. Bolting is a reasonable idea for the rudder end but the bearing end is a problem unless you have tapping and countersinking abilities, or care to assemble the rudder to the shaft in the water by drilling the stub above the shaft bearings.

To answer your question, a welded repair by a competent welder with good materials, in mild conditions, should make a 100 miles. But you're putting yourself, the boat and possibly others at risk doing it, and you have to replace the rudder anyway. As far as a 1000 miles goes, even coastwise, at best you get to wear the CG required life vest/dunce cap on your tow in, at worse you wind up a statistic.

Maybe it's better to cut your losses and just replace the rudder where you're at, rather than installing a questionably repaired one. Why do it twice?

Finally, the solid shaft recommendations above are a very good idea, and check if you've got some kind of electrolysis problem. That is some seriously rotten steel.

[SkiprJohn]

I'd appreciate knowing what boat this happened to. Just curious.
kind regards.

[Fog Bank]

Were it me, I would replace the rudder. Why tempt fate? Sometimes the universe clues you in on something, and when it does you should listen.just my thoughts...