Bandsaw noise issue

[mindpilot]

I'm cross-posting this from the beginning woodworking forum hoping that maybe some-one from SS will offer a fix.

From day one my bandsaw let out this annoying squeal seemingly at random. I finally got around to spending some time isolating the cause, and sure enough it is the lower guide bearing. I even removed it (of course it says "made in China") and soaked it some oil. Didn't help a bit.

It looks like SS got a batch of bad bearings. But the upper and lower bearing carry the same part number, wonder why we are all experiencing the problem with the lower bearing?

I'm going to try swapping the upper and lower bearing to see if the problem moves with the bearing or maybe it's more complicated that just a bad bearing. The problem does seem to be worse with wider blades

It's not the bearing--after swapping top for bottom, the noise is still there and it can still be quieted by stopping the lower bearing. The problem appears to be that it is impossible (without some serious modification) to adjust the lower mount so the blade centers on the lower bearing. In the picture below, I have hit the limit of the adjustment and the blade is nowhere near the center of the bearing. I did try replacing the lockwasher with a thin shim which actually seemed to reduce the noise, but the bearing outer housing ran uncomfortably close to the mount. The only other option would be to elongate the adjustment opening in the mount, but there is very little material there and removing enough to facilitate the adjustment would certainly weaken the mount. I am begining the think the best fix is to drill another mounting hole in the main housing. Does anyone else have this issue?

[dusty]

I'm cross-posting this from the beginning woodworking forum hoping that maybe some-one from SS will offer a fix.

From day one my bandsaw let out this annoying squeal seemingly at random. I finally got around to spending some time isolating the cause, and sure enough it is the lower guide bearing. I even removed it (of course it says "made in China") and soaked it some oil. Didn't help a bit.

It looks like SS got a batch of bad bearings. But the upper and lower bearing carry the same part number, wonder why we are all experiencing the problem with the lower bearing?

I'm going to try swapping the upper and lower bearing to see if the problem moves with the bearing or maybe it's more complicated that just a bad bearing. The problem does seem to be worse with wider blades

It's not the bearing--after swapping top for bottom, the noise is still there and it can still be quieted by stopping the lower bearing. The problem appears to be that it is impossible (without some serious modification) to adjust the lower mount so the blade centers on the lower bearing. In the picture below, I have hit the limit of the adjustment and the blade is nowhere near the center of the bearing. I did try replacing the lockwasher with a thin shim which actually seemed to reduce the noise, but the bearing outer housing ran uncomfortably close to the mount. The only other option would be to elongate the adjustment opening in the mount, but there is very little material there and removing enough to facilitate the adjustment would certainly weaken the mount. I am begining the think the best fix is to drill another mounting hole in the main housing. Does anyone else have this issue?

You say you can stop the noise by stopping the bearing. If you are not cutting (putting backward pressure on the blade) the bearing should not be turning. There should be a small gap between the blade and the bearing.

If there is a gap there shall be no squeal

This sounds like an alignment issue. I have had the same problem but after a very tedious alignment (per the manual) I have not had the squeal for about two years.

Yes, it does look to be not centered. (parallax I presume)

[JPG]

The lower bearing Should always be contacting the blade. This is the reason it squeals when the blade is moving(it has more wear and as has been mentioned it gets a lot of debris thrown at it).

The bearing pair at the upper rear positions the blade as it moves on to the upper wheel, and the lower bearing positions it similarly as it moves onto the lower wheel.

The upper bearing should just clear the back of the blade except when pressure is applied to the blade by the workpiece.

If the camera was positioned straight out from the blade(The pix was taken with the camera towards the rear)(notice the shadow and the back edge of the blade is visible) the blade would not appear off center as in the pix you posted. That would be parallalax.

[dusty]

The lower bearing Should always be contacting the blade. This is the reason it squeals when the blade is moving(it has more wear and as has been mentioned it gets a lot of debris thrown at it).

............

.

There is some disagreement here. In my opinion, the blade should not touch the upper and lower guide bearings when wood is NOT being cut. There should be a very small (1/16") gap between the blade and the bearing when the bandsaw is idling.

It is also very important (as has been said) that the bearing be positioned perpendicular to and centered on the bearing.

I do not believe that the squealing noise is the bearing itself. I believe it is caused by the scrapping of the blade against the bearing outer race when the bearing is not properly positioned.

I have spun bearings that have been removed due to the squealing noise and have not been able to reproduce that noise in the absence of the blade to bearing contact. If the bearing is the sole cause of the noise, I would think that the bearing would squeal when spun in this manner.

[RobertTaylor]

i believe the last paragraph in the pdf file agrees with jpg and myself.

[dusty]

i believe the last paragraph in the pdf file agrees with jpg and myself.

I understand why you believe that. It can certainly be read that way and if this is working for you - that is good.

Reading the entire pdf as a whole, I have chosen to adjust mine slightly different than apparently you do.

In addition to that, I am using different bearings than originally came with the bandsaw. I had forgotten that I made this change. I have installed a pair of bearings (627Z) in place of the single bearing in both of the guide bearing positions.

[ATTACH]6675[/ATTACH]

Footnote: The cool blocks are not properly positioned in this image.

[JPG]

I understand why you believe that. It can certainly be read that way and if this is working for you - that is good.

Reading the entire pdf as a whole, I have chosen to adjust mine slightly different than apparently you do.

In addition to that, I am using different bearings than originally came with the bandsaw. I had forgotten that I made this change. I have installed a pair of bearings in place of the single bearing in both of the guide bearing positions.

[ATTACH]6675[/ATTACH]

Footnote: The cool blocks are not properly positioned in this image.

I am curious how you chose to adjust it differently. What are you doing differently? The lower bearing is not adjustable front to rear. If the blade does not touch the lower bearing the blade is unrestrained approaching the lower wheel(when not cutting).

The bearing alteration should not affect in/out(assuming you are using 22mm bearings). Is it possible the groove between the bearings increases the bearing/blade spacing enough for the blade to clear the bearings? Is it possible your upper wheel is canted front to rear similar to the top bottom cant? (blade down side(open throat side) toward the tooth side of the blade?)

I truely believe the lower bearing is intended to serve two functions. 1) backup the blade while cutting. 2)Position the blade as it moves toward the lower wheel.


WHOOPS! I assumed you also changed the lower bearings. Didja? What width bearings are you using?

[mindpilot]

The blade barely contacts the bearing so sometimes it spins and sometimes it doesn’t, which must be the correct setting since there is no in-out adjustment of the guide bearings. Since the upper and lower bearing can be swapped with the noise source remaining on the bottom we know the problem is not due to the bearing itself, but a function of the bearing position and its contact with the blade.

The photo shows--without any significant parallax error--that even with the adjustment all the way to the right the blade is still probably 3/16” from the center of the bearing.

The noise is due to a combination of the bearing rotation and the back of the blade moving across the bearing face. I suspect the blade crosses the bearing face at a very slight angle which causes the squalling noise.

[dusty]

I know that it doesn't appears so but the blade does track right in the middle of the bearing set.

I think the guides bearings are the same as the tracking bearings but I'll have to confirm that.

[billmayo]

I know that it doesn't appears so but the blade does track right in the middle of the bearing set.

I think the guides bearings are the same as the tracking bearings but I'll have to confirm that.

Yes, the 2 tracking bearings (627Z) works well as a replacement for the upper and lower blade guide roller bearings. I adjust the upper blade guide so the saw blade tracks in the center between both bearings and just touching them. I use a higher precision 627Z bearings (6) when doing this task. I normally do not change from using the roller bushings in the older bandsaws. I just use a good grade of axle grease to lubricate them.