Bent Rudder Shaft - Fix or Use

[Sailorman Ed]

I knew the shaft was bent when I bought the boat in the fall but finally dropped it and got a good look at the bend. PO had sailed the boat from NYC to Annapolis, said was no problem. The bottom of the shaft is probably moved aft about 3". Thick walled SS tubing 50 mm dia (2 in). I can see uneven wear at the bottom Delrin bearing. The yard says they can straighten the shaft but will destroy the foam part of the runner, problem is they want a full charge to lift the boat 3 ft and then lower it back down. So 3 choices:

• sail it like it is and lift and repair the shaft next winter
• drop the rudder when we go back into the water and fix it while we sail until the fall ( will do little sailing this summer/fall and will be focused on interior issues, might be able to install it with a good 6 ft tide and a little digging in the sand
• ignore the issue and check it when the tide drops and can view it.

[Dave852]

Leave it like it is or replace the rudder. If you straighten the shaft it will fatigue and snap at some inconvenient time down the road.

[NahanniV]

I don't know what you are planning to do with the boat, but if it were me, I would either leave it for now or fix it.

For me fixing it would be a new shaft and rudder. Plus rudder bearings if needed.

Cheers,
JM.

[pbiJim]

Do you know what alloy it is? Do you know what heat treat it has? Do you know if it needs to be annealed before being bent back? Do you know if it needs to be heat treated after?

There are lots of things to consider.

[Greggegner]

I would done it once and do it right. Replace the bearing and the shaft. You will have confidence your boat. It will not be that much more, especially if you include heat treatment and inspection. I am not sure how to tell if you have a week spot...x-ray?

[Cotemar]

1) sail it like it is and lift and repair the shaft next winter is what I would do

[colemj]

Are you sure it is bent? Is it different than the other? It seems like a 3" bend would jam the top of the rudder against the hull.

Mark

[Sailorman Ed]

Mark - sure it was bent as the trailing edge jammed up against the hull and the PO cut some of the foam off. I just had new clamps for the connection arm machined in China (no charge). I am thinking now to have my china sources located some tubing of the appropriate alloy and cut me a new shaft. And then build a new rudder and install it at a later date. I think the cost should be nominal assuming they can get the correct alloy. (I source injection molds in china on a continuous basis and they are happy to do a little favor for me). What SS alloy is ideal?

So do I drop the rudder/shaft when they lift me back into the water and use only 1 rudder for the limited sailing I will do this summer/fall? How much control will I lose with only 1 rudder?
Ed

[Dave852]

It's doable depending on the boat but you will not be able to over come any weather helm at all. So no main or always with three reefs. Once you are in the slings, after you drop the rudder, knock the bottom bearing out from above hopefully if you have room or an emergency steering access port, get a good measurement of the outside diameter and make a template of the rudder. (You can make the template anytime, don't have to wait to drop it) then shove it all back before they splash you. When you receive your new rudder it is relatively easy to install in the water if your new bearing is a close fit.

[donradcliffe]

I didn't realize it was a cat until your last post. I would sail this season with both rudders, but recognize that they might not be well aligned, which will slow you down some.

The other option would be to drop the rudder in the water and try to straighten it yourself. I helped a friend do that one time--we put the rudder between the ground and the keel of a large cruising boat in the yard, then put a long piece of pipe over the shaft, and pried up until we took the bend out. I asked him whether he was worried about the shaft becoming more fragile due to strain hardening, and he said not for one bend/straightening cycle (it was bent worse than yours). He should have known, as he was in charge of the group which designed SS piping for GE's nuclear plants.

[Sailorman Ed]

Originally Posted by Dave852

It's doable depending on the boat but you will not be able to over come any weather helm at all. So no main or always with three reefs. Once you are in the slings, after you drop the rudder, knock the bottom bearing out from above hopefully if you have room or an emergency steering access port, get a good measurement of the outside diameter and make a template of the rudder. (You can make the template anytime, don't have to wait to drop it) then shove it all back before they splash you. When you receive your new rudder it is relatively easy to install in the water if your new bearing is a close fit.

Dave, a good suggestion. Each rudder has a length of line attached to a ring at the top of the shaft and above it, there is a small access port in each hull. I could get measurements while they are taking me to the water (I am about as far from the launch site as possible in the yard)
Ed

[Dave852]

Maybe they can work with you? Perhaps lift you in the slings at the end of the work day and splash you first thing in the morning? Below is a picture of how I mapped my rudder.

[Sailorman Ed]

Thanks Dave - good suggestion for "mapping"
Ed