DIY sealing for the rudder shaft. Will it work?

VandKoala

VandKoala

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Our (brass?) rudder gland has crumpled and we had to replace it.
We went with a bronze Vetus rudder gland. It has two O-rings inside it, one at the bottom and one at the top.
O-ring.JPG

The problem: Dropping the rudder to replace the o-rings after they wear out will not be desirable as it is skeg-hung and completely glassed in on skeg.
The idea: Create an additional sealing solution at the top, that can be replaced without dropping the rudder.

I have made a 3d-printed prototype, that fits standard 40x52x7 gasket/seal (1) for the shaft (2).
gasket.JPGSeal.JPG

Assembly.JPG


I could order one machined in bronze, but I am not sure this solution would work overall. The top of the bronze gland is slightly above/at water level, I do not expect much pressure.

Are there any experts here with practical experience that could tell me if this should work or not and why?

Cheers!
Koala
 
That would be just like a lot of other rudder shafts such as the Westerly W22 etc.

I wouldn't want to rely on a bit of 3D printing for the cap unless you were running a high infill, dont think I'd go for the expense of bronze either, probably just one of the engineering plastics
 
DinghyMan said:
That would be just like a lot of other rudder shafts such as the Westerly W22 etc.

I wouldn't want to rely on a bit of 3D printing for the cap unless you were running a high infill, dont think I'd go for the expense of bronze either, probably just one of the engineering plastics
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I checked that one in SS 304 would be about 45$.
Will probably get it cnc’ed
 
I think it should work if you also apply a greaser nipple and a bleeding hole with nut, to inject silicon grease between lip seal and the o ring. Lip seals need some kind of lubricant to be functional like water, oil or grease ( from the side it faces down).
 
Akestor said:
I think it should work if you also apply a greaser nipple and a bleeding hole with nut, to inject silicon grease between lip seal and the o ring. Lip seals need some kind of lubricant to be functional like water, oil or grease ( from the side it faces down).
Click to expand...
I can do that. But I assume there eventually would be some water :) Maybe some grease wouldn't hurt anyways
 
DinghyMan said:
And dont forget to either buy stainless steel springs for the seals or easier just replace the springs with O rings
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What is the role of a spring in a seal? Because I see some of them come with springs, some with double springs on both sides, and some without any.
 
Daydream believer said:
If the seal is meant to rotate against the threaded part it will not last long. Nor will it seal in the first instance.
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No, it presses to the top of the brass gland, and it is nice and flat. The threads are on the sides. The seal is a tiny bit smaller diameter than the bronze gland
 
I would want to machine in a little retaining groove beyond the threads (and smaller diameter) to avoid any chance of the ring being squeezed into the thread space. Not a particularly tricky bit of machining.
 
PCUK said:
Why not use lip seals? You can press them in and hook them out without moving the rudder.
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There is a round? I guess groove inside for a sealing ring. Maybe it would be actually possible to get it out and push a new one in. Now idea how it could be done though
 
At the upper end of the brass threaded bush looks like an O Ring that is generally used for sealing a shaft that rotated slowly as in a rudder shaft.

Ifs generally when you have a shaft hat rotates quite fast liked a prop shaft that you need a lip seal/

Engines and gearboxes will use li seals to seal the prop shaft and gearbox shafts to keep the oil in.

My hydraulic steeling pump and cylinder have O rings to stop the hydraulic oil from leaking out and retaining the oil pressure.

I think your 3 D printed cap and lip seal is a little over kill unless the O ring is much below the waterline or worn out in which case just replace the O ring
 
rogerthebodger said:
At the upper end of the brass threaded bush looks like an O Ring that is generally used for sealing a shaft that rotated slowly as in a rudder shaft.

Ifs generally when you have a shaft hat rotates quite fast liked a prop shaft that you need a lip seal/

Engines and gearboxes will use li seals to seal the prop shaft and gearbox shafts to keep the oil in.

My hydraulic steeling pump and cylinder have O rings to stop the hydraulic oil from leaking out and retaining the oil pressure.

I think your 3 D printed cap and lip seal is a little over kill unless the O ring is much below the waterline or worn out in which case just replace the O ring
Click to expand...
As I wrote - to replace the O-ring I will have to drop the rudder. Which means boat out of the water + sand down 1.5cm of glass from the skeg to get access to the bronze plate that attaches rudder to the skeg and then all the glass work to put it back in :) I am not sure how long will it take the O rings to wear out. There is one at the top of the sleeve and one at the bottom. I guess, the time will show...
 
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