Where can I buy gliding rudder bearings?

[Maika]

My old rudder bearings are pretty worn, and probably also made of nylon, which create a lot of friction. I thought I might get new ones, I guess preferably made of Ertalyte TX, Teflon, Delrin, Tufnol, Orkot or Maritex(?), so I contacted Jefa rudder, but they have only roller bearings. I don't need that, and I also really do not want to change the rudder tubes, so what are my options? Are these standard size, or do I have to ask somebody to make them?

[Dsanduril]

I would try my local bearing shop (industrial) rather than a marine shop. Given your location I don't know anybody local, here I would use King Bearing or Motion Industries. What you have pictured is a pretty standard flanged bearing (or flanged sleeve bearing). I found them here in the US in 40x48 (ID/OD) in many materials, but couldn't find your exact size.

I did have the same problem last time I replaced ours (I had inch bearings, and was in a metric location), and getting them turned at a machine shop was quite easy and inexpensive. I purchased some Delrin bar stock of the correct dimension and then took it to the shop to have it turned. I think it took them about 15 minutes to make the pair.

Just for reference (since I don't think these will help you directly, but will I hope give you the idea of what is available on the industrial side):

https://www.ametric.com/images/docum...etricNylon.pdf

http://www.buntingbearings.com/pdf/B...g%20040610.pdf

[donradcliffe]

I doubt the old ones are nylon, because nylon swells when it is wet. I had some delrin replacement bearings made in a machine shop. The only trouble with them was that they were an interference fit in the SS bearing holders, and the shop made the so that they just slid on the rudder shaft when they were not in the holders. After I pressed them into the holders they were too tight on the shaft.

When I put them in, I drilled a small hole into each one from the outside of the holder and put a grease nipple on the outside. That allowed me to easily grease the bearing once/year.

[PDScott]

Maika: Using a set of calipers get the exact measurement of you rudder stock. Take the old bushing(bearing) with you and a machine shop will make them for you. They need the old one for the height and OD measurement. Only the ID is worn. Not a hard fix. Peter

[Cheechako]

I would imagine they are not custom, but maybe they were. If you can find a machine shop, most of the stuff machines easy. Don't use Nylon. I really don't know what the latest "best" material is, but a little on line research ought to ferret that out.

[zstine]

Delrin is a pretty popular material for rudder bushings. Delrin does not need to be lubricated with grease or oil. In fact, it is not recommended to use grease or oils with plastic parts like Delrin as some oils/greases can cause swelling. Delrin is hydroscopic and will grow slightly when in the water. (0.9% per ASTM D570).. Which brings me to a question the OP needs answered. What size to machine the ID? I assume you can copy the outer dim's, but the worn ID needs to machined smaller... How much smaller? What size is the pin that goes through it? how much clearance do you need? I can't answer this, but you need to know before machining or buying the bush.
luck

[msponer]

I'd like to add that our first attempt at new delrin bearings on our skeg were WAY too tight. For us, the fit that worked was 'easy' -- the new bearing easily slipped onto the shaft by hand. I don't know what that was in thousandsths.

[Cheechako]

Originally Posted by zstine

Delrin is a pretty popular material for rudder bushings. Delrin does not need to be lubricated with grease or oil. In fact, it is not recommended to use grease or oils with plastic parts like Delrin as some oils/greases can cause swelling. Delrin is hydroscopic and will grow slightly when in the water. (0.9% per ASTM D570).. Which brings me to a question the OP needs answered. What size to machine the ID? I assume you can copy the outer dim's, but the worn ID needs to machined smaller... How much smaller? What size is the pin that goes through it? how much clearance do you need? I can't answer this, but you need to know before machining or buying the bush.
luck

For swelling of the plastic the ID should be machined bigger, not smaller. Although .9% is less than .002" on a 2" diameter shaft, so maybe not a concern. Wear may make up that amount.

[model 10]

A simple search for plastic bearings is overwhelming. I know that Delrin is used on accessory drives in turbine engines. Nice looking material. Any machinist will know but about .003 or so for something that does not expand is pretty good, so if you used the above factor someone mentioned you would be good.

[AD28]

Mine are quite similar, I couldn't find anything like, and so I had them machined up.

I bought UHMW stock from McMaster-Carr, handed it and the old bearings to a machine shop, told them the tolerances I needed, and had them turn the new bearings out. cost: $60 for the stock, $100 to machine, got four bearings for that.

[zstine]

Originally Posted by Cheechako

For swelling of the plastic the ID should be machined bigger, not smaller. Although .9% is less than .002" on a 2" diameter shaft, so maybe not a concern. Wear may make up that amount.

yes, absolutely Cheechako. To account for swell you need to machine the ID bigger. And yes, the swell probably should be ignored as it is so small. When I said to machine the ID smaller, I was comparing to the old bush's ID which has been worn. So the new ID should be based on the pin size (IMO), not the old bushing. I'm not sure how much clearance you need to have an easy turning joint, but without slop. I'm guessing the ID of the bush should be around 30 thousandths (0.030 inches) bigger than the pin's OD..?? But the pin is often ovalized

[Terra Nova]

For you high rollers, the hot setup is roller bearings from Edson Marine. Installation is quite a bit more involved. Did such an install on a Beneteau First 435.

[chris95040]

Originally Posted by Cheechako

For swelling of the plastic the ID should be machined bigger, not smaller. Although .9% is less than .002" on a 2" diameter shaft, so maybe not a concern. Wear may make up that amount.

2" x 0.009 = 0.018", which is not insignificant.

Check out mcmaster-carr btw. Great web interface to locate whats available in the sizes/form factors/materials you can live with. They've got decent info about what materials are suitable for what purpose, too.

[sy_gilana]

Vesconite Manufacturer Home Page: Low maintenance bushes and bearings
They probably have yours in stock. Best material out there.

EDIT...


Try this

http://www.vesconite.com/design/bush...rudder_imp.htm

[sueanderic]

hi,
I found a German company that makes all kinds of plastic compound sleeve bearings for many applications: IGUS, they are on the internet. I have used the bronze substitute bearings.
These are not expensive.
cheers, Eric