Bottom Rudder Bearing

[steelaway]

Hi all

 

Has any one tried any thing different to a steel bottom bearing?

Bronze ? - Nylon ? Stainless ball bearing ?

It has lasted 5 years so maybe I'm being a bit too bothered.

 

Alex

[Timleech]

Hi all

 

Has any one tried any thing different to a steel bottom bearing?

Bronze ? - Nylon ? Stainless ball bearing ?

It has lasted 5 years so maybe I'm being a bit too bothered.

 

Alex

 

I've bushed several with

Vesconite

 

but not had any back yet to see how they have performed.

 

You'll always get wear of the steel pin - ie the tip of the rudder post - and you have to have enough clearance to allow for slight misalignment or bending of the post, so probably wasting your time if you want to achieve a good long-lasting fit.

 

I doubt that any sort of ball bearing would last more than a few weeks in that sort of environment, but willing to be shown to be wrong

 

Tim

[nb Innisfree]

Hi all

 

Has any one tried any thing different to a steel bottom bearing?

Bronze ? - Nylon ? Stainless ball bearing ?

It has lasted 5 years so maybe I'm being a bit too bothered.

 

Alex

 

Hi Alex

 

I machined a nylon or similar cup to fit in bottom bearing, been there over 5 years and has been very successful, blob of grease when we dry dock prob not needed but tiller stays super smooth.

 

Chris

[Speedwell]

When I was still at work and had access to such things, I had something made up to prevent further damage to the heavily corroded bearing cup. This involved a stainless steel disc, located in the cup, then a disc of nylon and then another disc of stainless steel to carry the weight of the rudder assembly. This gave a much larger load bearing area. There was no wear when last I saw it out of the water but that was a long time ago, when the boat was sold in 2001.

Arthur

[steelaway]

Hi Alex

 

I machined a nylon or similar cup to fit in bottom bearing, been there over 5 years and has been very successful, blob of grease when we dry dock prob not needed but tiller stays super smooth.

 

Chris

 

 

Hi Chris

 

Just what I wanted to hear

I have some stock of the black bearing type nylon (forgot the name)

I'll machine out the bottom block and make a nylon sleeve to fit.

I have removed the steel bearing block today and found that the rudder has worn (pretty round) down to 37mm from 38 mm but the steel bearing has worn to 40+mm.

It has been suggested that a piece of stern tube material (11/2" - 38mm) would do a good job on an new rudder bar, but I think nylon will be perfect.

 

Alex

[nb Innisfree]

Hi Chris

 

Just what I wanted to hear

I have some stock of the black bearing type nylon (forgot the name)

I'll machine out the bottom block and make a nylon sleeve to fit.

I have removed the steel bearing block today and found that the rudder has worn (pretty round) down to 37mm from 38 mm but the steel bearing has worn to 40+mm.

It has been suggested that a piece of stern tube material (11/2" - 38mm) would do a good job on an new rudder bar, but I think nylon will be perfect.

 

Alex

 

Expect you already know but just make sure rudder post is supported on it's sides rather than it's end.

Edited October 8, 2010 by nb Innisfree

[Timleech]

Expect you already know but just make sure rudder post is supported on it's sides rather than it's end.

 

 

???

[steelaway]

Expect you already know but just make sure rudder post is supported on it's sides rather than it's end.

 

 

 

Mine is supported by a ball bearing block at the top.

 

Alex

[Timleech]

Mine is supported by a ball bearing block at the top.

 

Alex

 

You'll often have less trouble with vibration if the weight is taken on the end.

 

If using nylon, don't forget to allow for its expansion in water. The oil-bearing types expand less, but they still do it.

 

Tim

[nb Innisfree]

Mine is supported by a ball bearing block at the top.

 

Alex

 

Sorry, assumed you had a taper on the bottom of the rudder stock which fits a corresponding female taper in the bottom cup, takes all the weight, stays central (supported at the sides)and doesn't rattle.

 

Edited to add pcture

 

Edited October 8, 2010 by nb Innisfree

[Timleech]

Sorry, assumed you had a taper on the bottom of the rudder stock which fits a corresponding female taper in the bottom cup, takes all the weight, stays central (supported at the sides)and doesn't rattle.

 

 

I've never seen one like that, if it were tapered and a half-decent fit it would jam up at the first excuse. My guess is that yours has worn to a taper (They often tend to do so).

 

Tim

[nb Innisfree]

I've never seen one like that, if it were tapered and a half-decent fit it would jam up at the first excuse. My guess is that yours has worn to a taper (They often tend to do so).

 

Tim

 

It's been like that since I had the shell built, post and cup tapered to fit, quite common on modern boats I believe? They don't jam but lubrication does help to stop any squeaking hence the nylon insert.

[soldthehouse]

I've never seen one like that, if it were tapered and a half-decent fit it would jam up at the first excuse. My guess is that yours has worn to a taper (They often tend to do so).

 

Tim

As the actress said to the Bishop

 

 

Hat coat Bed

[Timleech]

It's been like that since I had the shell built, post and cup tapered to fit, quite common on modern boats I believe? They don't jam but lubrication does help to stop any squeaking hence the nylon insert.

 

[OLDFARTMODE}

 

Been docking boats for over 40 years, never seen one like that

 

[/OLDFARTMODE}

 

 

Quite seriously, if both halves are tapered and there's weight on it, it WILL jam up.

 

Tim

[Evo]

Most rudders seem to be hanging from the top off of a sealed bearing these days dont they ? the bottom of ours seems to float about a fair bit. I assume this is because the bottom is worn. From what your saying i guess i could undo the grub screws on the bearing and tap the rudder down a bit untill its sitting on the bottom of the shaft....is all this correct, and would it be worth trying to tap it down. When it comes out the water I'll have a proper look at it and see whats what

[nb Innisfree]

[OLDFARTMODE}

 

Been docking boats for over 40 years, never seen one like that

 

[/OLDFARTMODE}

 

 

Quite seriously, if both halves are tapered and there's weight on it, it WILL jam up.

 

Tim

 

Depends on the amount of taper, a pronounced one is ok, our rudder has always been easy to lift out, about an inch, and is held centrally at the top with a standard plastic and O ring bearing i.e. the whole weight is taken on the bottom cup on the skeg.

Edited October 8, 2010 by nb Innisfree

[Timleech]

Most rudders seem to be hanging from the top off of a sealed bearing these days dont they ? the bottom of ours seems to float about a fair bit. I assume this is because the bottom is worn. From what your saying i guess i could undo the grub screws on the bearing and tap the rudder down a bit untill its sitting on the bottom of the shaft....is all this correct, and would it be worth trying to tap it down. When it comes out the water I'll have a proper look at it and see whats what

 

Yes, I'd give it a try if you have any trouble with it rattling. Try to leave it free to slide in the top bearing so the weight is on the bottom.

 

Tim

 

Depends on the amount of taper, a pronounced one is ok, our rudder has always been easy to lift out, about an inch, and is held centrally at the top with a standard plastic and O ring bearing i.e. the whole weight is taken on the bottom cup on the skeg.

 

The angle would need to be greater than that in your little sketch That looks to be about the same as a standard (milling etc) machine spindle taper, where the taper is used to drive the tool!

I know, it's only a sketch & not a scale drawing. I'd be interested to see one like that, I can see the idea behind it but not yet convinced

 

Tim

 

Edit to add - maybe it's intended to double as a friction damper

Edited October 9, 2010 by Timleech

[hughc]

The most successful arrangement we have found is to have large diameter, 2" perhaps, rudder stock turning in cast iron bearings top and bottom. These are shrunk into steel shells to aid welding and the bottom one is cup shaped and welded to the skeg at the same angle as the rudder stock so that the stock sits squarely on the bottom of the cup. Regards, HughC.

[Timleech]

The most successful arrangement we have found is to have large diameter, 2" perhaps, rudder stock turning in cast iron bearings top and bottom. These are shrunk into steel shells to aid welding and the bottom one is cup shaped and welded to the skeg at the same angle as the rudder stock so that the stock sits squarely on the bottom of the cup. Regards, HughC.

 

Basically the same as on working Narrow Boats, never been improved upon! The vast majority of modern boats have steering gear which is too skinny, which is why so many have problems with vibration.

 

Tim

[Guest]

The most successful arrangement we have found is to have large diameter, 2" perhaps, rudder stock turning in cast iron bearings top and bottom. These are shrunk into steel shells to aid welding and the bottom one is cup shaped and welded to the skeg at the same angle as the rudder stock so that the stock sits squarely on the bottom of the cup. Regards, HughC.

Just to enlarge on that slightly: Is the bottom of the rudder stock rounded and running in a cup shaped bearing, or am I misunderstanding?

Thanks.

[nb Innisfree]

Better pic from earlier post, edit function is playing me up

 

Edited October 10, 2010 by nb Innisfree

[steelaway]

Just to enlarge on that slightly: Is the bottom of the rudder stock rounded and running in a cup shaped bearing, or am I misunderstanding?

Thanks.

 

 

Hi

 

My rudder stock is 11/2" and a piece of round steel bar 3"x 2" with an 11/2" hole is welded onto the skeg for it it to pivot in - simple but prone to wear.

 

Alex

 

 

[nb Innisfree]

Alex

The bottom of you rudder stock looks tapered, is that so?

 

Chris

[steelaway]

Alex

The bottom of you rudder stock looks tapered, is that so?

 

Chris

 

 

Hi Chris

 

It is abit now its worn!!, but it was a straight piece of 11/2" bar. Cheap and cheerful.

 

Alex

[PaulD]

Hi

 

My rudder stock is 11/2" and a piece of round steel bar 3"x 2" with an 11/2" hole is welded onto the skeg for it it to pivot in - simple but prone to wear.

 

Alex

 

 

 

Alex,

 

Did you use Stilsons to tighten your prop nut?

 

Paul