rudder bearing lubrication etc

[ongolo]

Hi All,

I have a transom hung rudder on my steel schooner. The rudder shaft is in two sections.

I need to protect the flanges and the bolts as well as the shaft turning in veconite cups. My boat is not a "yacht", has a black hull and I dont mind using tarr or the likes. For instance my gaff saddles are covered with raw hide.

I would if possible, rather go for something traditional.

Also the bolts holding the quadrant to the shaft need to be covered with something.

My rigging screws (I did not go for dead eyes) are covered with greased cloth and then wrapped in bitumen soaked cloth.

So I dont mind to use what fishermen used 100 years ago.

regards ongolo

And thanks for the help in the past, I am off soon, but I dont know where. So please dont ask. It will not be the Carribean and it will not be the USA. Maybe just up the coast or down the coast, or the Indian Ocean. I dont know, still looking for direction. Someone inquired to charter my boat for research, I would like something interesting.



<hr width=100% size=1>So what......... it floats

 

[Peterduck]

What materials have you used for those bolts and the rudder shafts, Ongolo? Any steel above water level should be hot-dip galvanised, but that won't last below the waterline. 100 years ago the builders had access to wrought iron, which does not corrode as quickly as steel, but this is now difficult to get. I'll have a think about this one, but I don't have an answer off the top of my head.
Peter.

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[ongolo]

Hi Peter,

I have had a horrific failure of a stainless bolt and done away with that rubbish.

I find that galvanized bolts dont make much of a difference as far as corrosion goes. Not here anyway where even 316 rusts.

Also here we dont get galvanized 8.8 or better bolts. So I used high-tensile bolts. They are located in the splash zone.

In a year or so, I will make a new rudder with a solid shaft that has no flanges, but in the meantime I have to find a solution.

The new rudder shaft does away with flanges, but it leaves the problem of the bearing block.

thanks peter

regards ongolo


<hr width=100% size=1>So what......... it floats

 

[Peterduck]

Well,Ongolo, you have a steel boat and that has a protective coating system; why not continue that over the bolts? You'll have to be very particular about bedding in whatever you bolt down so that seawater cannot get between the two components and rust the bolts out in the middle. I really don't know what to recommend for underwater fastenings. With a wooden boat, which is what I am used to, I'd say bronze fastenings, but in your case they will only accelerate any corrosion that can happen to the hull itself. I have been using 1/4" thick plates of mild steel as anodes for the past few years, very successfully. They reduce to wafer thin in 12 months and disappear in about 15 months. Properly painted steel yachts here have no problems. though. The splash zone, as you obviously realise, is the zone of highest oxidation. I wish I could be more helpful.
Peter.


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[ongolo]

Hi Peter,

Thanks, I suppose I have to monitor it and replace the 4 bolts of the bearing cup regularly. Or go for stainless, but I am scared of failure.

regards ongolo


<hr width=100% size=1>So what......... it floats

 

[Plum]

Don't bother with expensive materials, just use the cheapest steel bolts of the correct strength you can find and take plenty of spares with you. I recommend you apply bitumen paint to all surfaces, flange faces and nuts and bolts as you assemble. Once assembled, paint all with a few more coats of bitumen paint. Once the paint is dry coat the whole lot in your favourite waterproof grease. That should last 3 years, maybe 5 or more. If you can get hot dipped galvanised bolts the above treatment could last as long as 10 years. This all assumes that you regularly maintain the grease coating. Keep a supply of spare nuts and bolts on board and also, most important, a nut splitting tool so you can remove rusty bolts even if the threads are corroded.

Hope this helps.
Hope this helps.

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[penfold]

You could try wrapping the flange and bolts with Denso tape if it's available where you are. In the UK it's often used by utility companies to protect flange bolts on underground pipes. But on balance it's probably no more effective than painting them and replacing them at regular intervals.

cheers,
David

<hr width=100% size=1>What we are dealin' with here is a complete lack of respect for the law....