Bearing Interference fit problem on shaft in wheel - how to solve using only temperature differential if possible - already tried and failed.

[maple syrup]

If you heated the bearing up to 300F, throw it out and get a other one, it’s scrap. Heating it up that hot removes the hardness from the steel and it won’t last anywhere near as long as it should. You should not heat a bearing any higher than about 210-220F. You could have degraded the grease as well.

Your measurements are almost exactly 17mm, that is what the shaft should be for that application. You should only need a little bit of heat to get it on the shaft if the bearing is on the smaller end of the tolerance, if at maximum size, it might even slip on. I would take a look at the shaft and find out why the bearing is not going on, if someone banged on the end, it could be belled enough the bearing will never go on, the shaft could be oval, so check in three spots, ie 12 o’clock, 4 o’clock and 8 o’clock.

No. It was heated up to 200 Fahrenheit. I also use dry ice which is -100 which is a 303 different. I will check the shaft as you say

 

[maple syrup]

Update
Everything went smoothly except for the final second. I didn't realize until was too late and everything cooled down. the shaft was sanded down, but not enough apparently. The wheel was heated and the shaft was placed in. It fell right through both bearings with no effort but stopped 2 mm short. I did give Very light hammer at that time but no movement. I thought it bottomed out. After a cool down I was able to see why. There is a groove for the snap ring in the front. I stoned The groovedown a little bit Before placing it in anticipating something like this.. given the distance there is no doubt that the shaft got stuck on the edge of snap ring groove. I don't think I sandedd it off enough for slip fit. even so I'm not sure why didn't fall the way through. You can see in the photograph the 2 mm distance between the bearing and the back of the shaft.

I'm now stuck in a funny situation. Trying to figure out how to solve this. Please give your opinion

1. Hydraulic press. - Bearing damage?
2. heat whole wheel back in oven to 200°F. Get a piece of dry ice, And stick it on the shaft to melt it. give it some love taps.My gut is telling me this isn't going to work
3. disassemble- but how without damaging the pricey bearings?
4. Purchase new bearings and restart?
5. other?

 

[John O]

Looking at the sites for Delta bandsaws, you should no need any heat or cooling. Center shaft is slip fit and bearings to wheel slight interference.
Circlip stops wheel from coming off shaft.

Replacing bearings on Delta 14" band saw wheels

Hi I have a 22 year old Delta 14" band saw Model 28-470. I'm currently replacing the 1 HP motor which fried itself without warning. Putting in Leeson 1 HP TEFC model. A few questions: The bearings in the upper wheel of the saw seem a little bit stiff and I wanted to replace them...

sawmillcreek.org

 

[Asm109]

4.

 

[Beckerkumm]

Since the fit is tight on both inner and outer, I'd made a disk to fit the bearing and bore out enough for the shaft to fit through so the disk is pushing both inner and outer and press the bearing on using something like a large socket to clear the shaft. The even distribution will not hurt the bearings but as others have said, there should not be a tight fit on both races. If the bearing were not running so slowly, that would spell disaster when the bearing warmed up and was forced to expand towards the balls. Normally in this application, you only need to press on the race that is the interference fit and not worry about the slip side. There must still be some problem for both to be tight. Dave

 

[maple syrup]

Looking at the sites for Delta bandsaws, you should no need any heat or cooling. Center shaft is slip fit and bearings to wheel slight interference.
Circlip stops wheel from coming off shaf

You are correct. This is the way it should be. But for this particular saw, which is an oddball design, it does not appear to be the case.

Since the fit is tight on both inner and outer, I'd made a disk to fit the bearing and bore out enough for the shaft to fit through so the disk is pushing both inner and outer and press the bearing on using something like a large socket to clear the shaft. The even distribution will not hurt the bearings but as others have said, there should not be a tight fit on both races. If the bearing were not running so slowly, that would spell disaster when the bearing warmed up and was forced to expand towards the balls. Normally in this application, you only need to press on the race that is the interference fit and not worry about the slip side. There must still be some problem for both to be tight. Dave

Yes. That is the reason how this whole thread started. That the inner race was supposed to be slip fit and it wasn't. I sanded it down, but apparently not enough. I'm ahead of you. I use an old bearing and grind it down with dremel tool. If I do this

1. the threaded side bearing would be okay as I could hold both the inner and outer race.
2. The snap ring side bearing race would be held also, but the inner race if it's not slip might screw up.

Summary: So at of the 4 races, in theory 3 would be okay if didn't sand it enough.

how do I know if I'm pressing too hard? I figured out a way to press in on with a bearing puller I think. I can also use a mallet. I don't know when using a mallet how hard is okay to hit

 

[John O]

If you need the shaft sanded down a bit and need a lathe I have one you can use.
I am home all weekend.