Rudder post tube- advice, please

[[32511]]

The rudder post on my Caprice passes through a tube in the stern locker. The lowest few inches of the tube look very rusty, and, as they are below the waterline, I am worried. As a raw newcomer, it looks near impossible to me to remove/ replace the tube without damaging the fibreglass hull. I was therefore thinking of removing the rust, and wrapping with glass fibre tape and resin. Is this advisable? Helpful advice, please!

 

[saltwater_gypsy]

The usual scheme is to raise the boat on blocks and/or dig a hole below the rudder or hang it over the edge of a slip, so that you can drop the whole assembly down and out of the boat. Then you can have a proper look at the problem.

 

[[32511]]

On this one, the rudder post pivots in the skeg. I believe that the post is removed upwards, as the rudder is bolted to it. There was some play in these bolts. so I added stainless taper pins in reamed holes, well clouted in. They might take a bit of removing. The main problem is the tube seems to be bonded into the fibreglass, with thickened bosses, top and bottom, and does not seem removable.

 

[machurley22]

I'm no expert but..

I presume this is (or was originally!) a galvanised steel tube? Do you know how thick it's walls are? How deeply are they corroded? Obviously you can only see the outside of the tube and are presumably worried about the remaining thickness. Is there much play?

Glassing in the tube would probably work for many years (make it strong) but won't do anything about what's happening inside the tube. It may not be any easier to get a good bond to the hull than it would be to re-glass a new tube into the hull.

Whether you replace or encase I can recommend a mod carried out by a previous owner of the good ship Silkie which is to fit a grease nipple to the rudder tube. Keeping the space between rudder stock and tube filled with waterproof grease seems like a good idea to me.

 

[PeterGibbs]

From your description it sounds like your rudder post tube is deteriorating and is glassed in to place, is part of the strucutre so cannot be easily removed etc. I would not try to get into this at this stage - the consequences to the hull could prove costly.

I assume you have removed all the rust you can to check the strength of the underlying metal. I guess it will not have corroded completely through so can be built upon.

Glass wrapping with a good seal to the hull should be effective in preventing any more external corrosion to the tube, but what of the internal surface which I assume faces the sea continuously?

You could also shape a piece of non ferrous metal to enclose the tube, and seal it into place - it is a backup after all and not subject to stress - from your account.

Or, you could take some heavy duty pipe of sufficient bore - exhaust grade would be good - and slip it over the tube and seal to the base: you might have to drop the rudder to do this, or just cut it longitudinally and strap / seal into place.

On my Bav, the rudder stock rises through a rubber tube with an open top (well above water level, of course) that is strapped to a metal base glassed in to the hull. I have never had to touch it.

Good luck,

PWG

 

[neil_s]

Your idea sounds like a good one. I had a wooden Hillyard boat with a galvanised steel tube rudder tube, just as you describe. it was also very rusty - but there was still plenty of metal thickness after 65 years of service. So don't panic!

Neil

 

[[32511]]

Thanks, guys- I'll go ahead and glass the tube, as it is not really stressed. The grease nipple sounds a good idea, if I can drill and tap without touching the rudder post.

 

[dam747iam]

try and get a broken windsurfer or grp mast cut to length and glass in place