Water in The Rudder

Ships_Cat

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Perhaps your posts would be of more value if they gave solutions rather than just trying to dismantle those of someone who typically gives the most authorative responses to the type of question raised by the thread's initiator.

So, how would you repair the original poster's rudder?

John

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oldsaltoz

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I suspect this might be a wind-up, but just in case........

From Your last posting:-
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<<< So the rudder should normally be full of air?!
I thought the keel and rudder were usually solid (with the odd air pocket) ... >>>
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No. most rudders are filled to reduce the amount of water that can enter, sadly the expanding used by some will not stand up to moisture, so it's important to use only 'closed cell' balloons as a filler.

A typical fibreglass rudder has a single shaft and at least 3 tangs, and an and plate; a good rudder has all stainless steel components, the tangs are shaped to form the profile of the rudder and extend around the front of the shaft, this provides for some balance and a larger weld area thus a stronger rudder to shaft interface, the trailing edge of the tangs should be slotted and a flat bar inserted and welded.

After pickling the welds to prevent corrosion, the frame is put on it's side in a mould, then filled with closed cell balloons and epoxy resin, it's exposed side is shaped using the tangs as a guide, when cured it's faired and glassed with epoxy cloth and resin, sanded and faired again, then given 3 or 4 coats of epoxy resin, lightly sanded again and primed ready for painting.

Some rudders are constructed of 'solid' timber, and timber floats, so provides a positive buoyancy also.

Keels are normally solid by the way.

Avagoodweekend.



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Avocet

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I suppose strictly speaking, the rudder should be full of whatever the designer intended it to be full of! I'm sure in most GRP yackts that will be "foam" and as OldSatlOZ says, that tends not to keep the water out indefinitely (but it is dirt cheap!) If I ever get round to re-doing Avocet's rudder properly, I shall be taking his advice and using epoxy thickened with something impervious.

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fireball

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Potentially misleading people by false statements isn't helpful either....

I don't know how I would go about repairing his rudder - to my knowledge I don't have air in mine... as a stab at the process I would go through if I had water in my rudder....

It would be worth evaluating how bad the void is - with a rough idea of the volume of water that has leaked out it can be guestimated as to the internal volume of the rudder that has a void, taken as a ratio to the volume of the rudder you can judge how significant the void is and whether action needs to be taken now or could be left and monitored.

I believe others have already mentioned splitting the rudder and exploring the cracks.

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fireball

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Thankyou for that clarification - the old boat had a solid wooden rudder that was encased in some glass/epoxy/whatever (didn't matter cos there was nothing wrong with it!) I assumed that all rudders would be of much the same (solid) construction and not filled like you said.

In this case a water filled rudder will weigh more than it should do!

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