[Globetrotter76]

Hi I thought I would come pick the brains out here.......Sure you will have all sorts of advice so here goes

Onboard I have Koopnautic Stabilizers. The bearings are used in the stabilizer rams.

I have been putting new Maintenance Free Radial Spherical Bearings and ran short of the bearing in my spares, order them I thought.

After chasing this bearing up, I hear that SKF are not manufacturing a batch of this specific bearing till December 08...which is out of the question as we are outta the yard in 2 months.

I tried to cross the part numbers with another manufacturere which is INA from Germany, I received the bearing from the bearing supplier here in Florida(He cross ref them with the original SKF bearing that I was looking for) So I thought it would be all good.

However when i tried to fit the bearing in they do not fit there is about 0.01mm interference in the fit on the pin for the id of the bearing and same with the OD which should slip nicely into the Stablizer Ram.....with the help of some locktie(All specs the same from SKF to the cross part INA bearing) This leaves me in a dire situation.

Does anyone have any ideas??

The SKF bearing number is GE25TXE-2LS and the INA bearing number is GE25-UK-2RS

Any ideas on how to find these hard to find SKF bearings?? I am in U.S.A....Maybe chase suppliers in Europe???

Anyway any input would be appreciated?

[Capt J]

Find a good machine shop and have them cut the bearings that you have on a lathe for the additional clearance that you need. That would probably be the easiest solution if the bearings you have a slightly oversized.

[Globetrotter76]

thanks captain J. Was actually considering that option.

[K1W1]

Hi,

If I understand your first post correctly you have a bearing where the ID is fractionally too small to allow the pin to go through and the OD is the same but this means that the bearing would be a sloppy fit in the hole it fits into.

Is this the situation you have?

Machining Bearings is virtually impossible, holes can be made in race in some cases for lubrication using a process called Spark Erosion.

[Ken Bracewell]

Originally Posted by K1W1

Machining Bearings is virtually impossible

We've had all of our SKF strut bearings machined by our boatyard in FL. Should I be worried about wear on the shaft?

[K1W1]

Originally Posted by Ken Bracewell

We've had all of our SKF strut bearings machined by our boatyard in FL. Should I be worried about wear on the shaft?

Ken, I doubt even on a boat built by Not Quite Entirely Accurate ( NQEA) would be using plain spherical bearings on the prop shafts. It was these that I was referring to above.

Also- I got a reply from an SKF Supplier in the UK saying that they can supply the required bearings above with 2 RS instead of 2 LS the basic bearing is the same just the lip or dust seals are different. The supplier is http://www.bearingboys.co.uk/Spheric...earings-1023-c

[Ken Bracewell]

Originally Posted by K1W1

Ken, I doubt even on a boat built by Not Quite Entirely Accurate ( NQEA)

Originally Posted by K1W1

using plain spherical bearings on the prop shafts. It was these that I was referring to above.

I guess I should have read the original post a little closer

[Marmot]

Ken,

MSC Industrial Supply lists several versions of the GE25 bearings. If the clearance on the OD is .01 mm, Loctite should easily handle that as it is very little clearance. If the bore diameter is .01 too small for the pin or shaft, you should be able to have it honed or ground to fit perfectly by a local machine shop.

[Globetrotter76]

Thanks for all your ideas and help, I finnaly managed to track down a supplier in the UK that stocks these bearings which are supposedly hard to fin here in the U.S

The id of the bearing had an interferance fit by about 0,01mm to the pin diameter. The od of the bearing had also about a 0.01mm interference fit

So even with the cross over bearing specs from one manufacturer to another it did not ensure that this was 100 percent sure thing, the machining tolerances are where my problem comes in.

So it should be all good when I get the SKF bearing.

Another learning curve I guess and thanks for all ur feedback.

I pop on the forums for browse everynow and then and great to see folks sharing knowledge!

Cheers

Globe76

[K1W1]

Hi,

Another thing- I don't know about the Koopnautic ones in particular but do know the Vosper units used to require the bearings and pins to be Loctited in, this makes for an interesting removal when you don't have the proper tools.

[Marmot]

" ... when you don't have the proper tools."

Fire is your friend.

The best law of thermodynamics ... Get it hot and it will move.

[Capt J]

Originally Posted by K1W1

Hi,

Another thing- I don't know about the Koopnautic ones in particular but do know the Vosper units used to require the bearings and pins to be Loctited in, this makes for an interesting removal when you don't have the proper tools.

Heating the part with a torch will totally free the loctite as it looses it's adherence properties at around 400 degrees F and actually works like a lubricant. Of course this can only be done with metal and not a part that has rubber, plastic, or wiring on it.

If the bearing is too small to fit into the pin it can also be knurled by a machine shop to make a tight fit.

[Globetrotter76]

I locktite the bearings into the eyes of the hydraulic rams and knocked old ones out using a socket of suitable size and a mallet.

I contacted Koopnautic and asked them for their reccomendation. They actually supply the rams with the INA bearings, the exact ones im having problems with. However I tried to slide the bearing onto another pin and it slipped on nicely, I sent the other pin to be machined the 0,01mm if that....and the bearing slipped on.

I then took the rams and placed the bearing(with locktite on mating surface), on the eye of the hyraulic ram I then used a suitably sized socket and mallet and tapped/hammered the bearing into the eye depending on the intereference, I have a few spare rams so tried a few till I found ones that the bearing could be tapped into the eye

Now i reckon that during the manufacturing process of the rams,pins and bearings there are going to be certain tolerances etc Hence the bearing fitting nicely on some and not so good on others.

So ive got a few rams and I will hold the INA and SKF in my spares.

Anyways thanks for input!