Rudder bearing

[jesperht]

Have some slack in my rudder bearings, and would like to get it fixed, but it is not just a change of bearings, since there are no bearings!
The rudder is attached at the hull, here there a no problems, but the lower attachment are. The axis is 50 mm stainless steel, running directly in a big bracket made of brass.
The brass bracket consists of two parts, a very solid part connected to the hull, and another small part connected to the big part by two M10 bolts. Between the two parts is the 50 mm axis. I have a slack of 1 mm appr..
My thought is to take the brass parts to get mascined to a bigger diameter, leaving place for 2 half moon shaped bearings, having a bunch of these made, so i will have some in the future. But what should they be made of? They should not be worn to fast, and corrosion must be avoid.
Or maybe someone has another suggestion?
The previos owner had reinforced the rudder, making it thicker than original, maybe this is causing exesive wear?

[bizzy]

there should be a cutlass bearing in the bronze housing. it sounds like the small part you refer to is infact a gland ,so tightening the two bolts makes the packing expand and keeps the water out .
a picture would help!

[jesperht]

I tried to attach a photo, hopefully it worked. There is no cutlass bearing, it is really simple made, the 2 bolts hold the smaller part to the big bracket. Both are solid brass.

[atoll]

these guys will make up shell's or bushes to your spec,expect at lest 10 years life out of bearings

Vesconite Manufacturer: Marine rudder and stern tube bearings / bushes.* The low friction, long life bearing material for wet and dry applications

[barnakiel]

It may be a cut piece of cutless in that bronze two part bracket.

If your shaft is a bit worn, you may experiment with metric vs. imperial to allow for this. Otherwise measure OD and ID and go for it.

It may be a solid bearing too - if so, avoid nylon when replacing. Any machine shop will make one to fit in metal or plastic.

b.

[BentP]

You allready answered yourselve; machine the brackets to a larger diameter and insert a two-part bushing. If the bracket is bronze ( hopefully it's not brass) then the bushing should be bronze too. Or else some POM-like composite.

[jesperht]

Hi Bent You are absolutely right, its bronze not brass, my bad english... That must be the way, i will have a hole bunch made! Anyone knows of a european company who can make such bushings in composite?

[BentP]

I think any decent machine-shop could do this. I would go with bronze, they should keep for quite some years. Just check the alignment with the rudder pole when assembling, you might need some foil sheet to adjust that.

[jesperht]

I will do that!
Any clever idea as to how i get the bushings to stay in place? The are about 2 cm rudder pole under the bracket, so the bushing will slide down unless i fix them. Suggestions?

[atoll]

Originally Posted by jesperht

I will do that!
Any clever idea as to how i get the bushings to stay in place? The are about 2 cm rudder pole under the bracket, so the bushing will slide down unless i fix them. Suggestions?

machine "shoulders" on the outer face to slot into the housing.

vesco plastics will do this for you if you send them a design.
i belive they have suppliers all over europe who will machine as well.
though any machinist in your local area will be able to do this as well

[pbiJim]

The stated plan sounds good to me. Another quick option would be to get some .020" thick shim stock & wrap the shaft. Shims can be had in several materials. Brass is one of the common ones. You can also try various thickness & then decide how much clearance you want to leave before having custom bushings machined.

Also, there are some good plastics out there these days that do well as bearing materials. Nylon 6/6, Rulon, Delrin UHMW, etc.

You have some options.

[barnakiel]

Drill the bracket and lock with a screw.

Cold / hot fit also works but would be a hell to remove one day.

b.

[BentP]

You need to have the bushing made with a shoulder which you can attach to the bracket with screws. It is not possible to just crimp it in, since the bushing is splitted into 2 halves.
I did it this way on the previous boat, worked like a charm.