Bandsaw Vibration, why?

[John Kananis]

Hello all: I have a serious vibration issue with my 14" Ridgid bandsaw. I've changed the tires out with polyurethane tires, I've swapped out the rubber motor mounts with plywood (and shimmed it into position with a block of wood), I've checked the alignment of the wheels with a level (top to bottom at once), the wheels spin freely with no wobble when I hand-crank (even under tension), it happens with various sized blades (even new ones), the guides are where they're supposed to be and tightened. I do not allow tension on the blade when not in use. Everything I can see aligns properly and the blade doesn't rub anywhere its not supposed to.

The gosh darned thing was never perfect but now its gotten out of hand (progressively worse and worse).

What haven't I checked? Thank you.

[John Donofrio]

Have you checked the balance of the wheels? Some are balanced using weights, maybe they (or some) have fallen off.

[John Kananis]

Thank you for the quick reply. The wheels never had any weights for balance. I'm confident I can make my own weights by drilling into the wheels and adding some bolts through the holes but I wouldn't know how to balance these without a balancing machine. Any thoughts?

[Erik Loza]

Thank you for the quick reply. The wheels never had any weights for balance. I'm confident I can make my own weights by drilling into the wheels and adding some bolts through the holes but I wouldn't know how to balance these without a balancing machine. Any thoughts?

Do this: Take a sharpie marker and number the spokes of the wheel in sequential order. Without a blade on, spin the wheel a few times and watch where it lands. If it keeps landing on the same number, you've got an out of balance wheel. As far as re-balancing it? May not be cost effective on that particular machine but perhaps someone with more experience on the smaller saws could advise better than me. Best of luck with it.

Erik

[John Donofrio]

You could use the spin test. Blade off, mark a wheel then spin to see what it does). It should not stop in the same place every time and it should not come to a stop and then rotate in the opposite direction at all. If it does, I would suspect it's out of balance.

There's plenty of instruction/videos on the web. Check out some search hits from 'balance band saw wheels'.

[John Kananis]

Thank you folks. I found some resources on how to balance the wheels; I'll update the thread once I've tried this.

[Lee Schierer]

A wheel is unlikely to just get out of balance on its own. Before drilling any holes check for sawdust accumulation on the back side of the wheels. I would check the belt for condition and proper tension. You can eliminate the balance issue for the upper wheel by running the saw without a band. Then remove the belt and run just the motor. Try a different blade as a kink in a blade or bad weld will act like vibration.

[Judson Green]

You say you swapped out the rubber motor mounts with plywood, why? And is the drive belt tensioned right? And smooth - no lumps?

[Morey St. Denis]

Once you're confident everything has been checked at the level of a cursory overview of the mechanism, potential interference or alignment issues, it's time to drill down to the next level of detail work... You'll want to determine the frequency of that vibration, does it more closely match motor revolutions or rotations of the drive wheel? You'll need access to a dial micrometer that can check for shaft run-out and axial play in case any bearings may have become worn. If convenient to eventually dismount the wheels down to their hub, you could likely use an inexpensive conical balance tool that can be found in the lawnmower maintenance section of a hardware store (mower blade balance) to check for any gross wheel imbalances. I'm rather suspect of the removal of OE rubber damping bushings in favor of the described much higher modulus plywood mounting scheme... Rubber mounts are provided with the intended purpose that minute dynamic vibrations are passively damped and not get transmitted nor harmonically amplified by steel frame components. During any of the previous work did it ever become necessary to "persuade" certain stuck components with an impact blow or an inadvertent drop of the hardware? Sometimes bearing raceways can manifest internal peening due to prior impact damage. Kindly let us know something more about the frequency of that vibration...

[Rich Enders]

My problem was the drive belt. The original A980 from Rigid was worn, but still running smoothly. I replaced it with a new Gates and the vibration was terrible even after a long run in. When I went back to the original belt the vibration disappeared. I tried a link belt and it is better than the Gates, but not as good as the old A980.

I am not sure how to search directly on Sawmill Creek, but if you Google The "Quality" V-Belt thread you will come to a lengthy Sawmill Creek discussion of the belt situation on 14" band saws.

[John Kananis]

Thanks for the heads up, Rich. The original belt was replaced with a notched type (went to auto parts and sized it up).

Lee: No saw dust accumulation, belt and tires are relatively new. Also, happens with any blade I install.

[John Kananis]

You say you swapped out the rubber motor mounts with plywood, why? And is the drive belt tensioned right? And smooth - no lumps?

I've seen it done before on this model saw and it did help a bit.

Once you're confident everything has been checked at the level of a cursory overview of the mechanism, potential interference or alignment issues, it's time to drill down to the next level of detail work... You'll want to determine the frequency of that vibration, does it more closely match motor revolutions or rotations of the drive wheel? You'll need access to a dial micrometer that can check for shaft run-out and axial play in case any bearings may have become worn. If convenient to eventually dismount the wheels down to their hub, you could likely use an inexpensive conical balance tool that can be found in the lawnmower maintenance section of a hardware store (mower blade balance) to check for any gross wheel imbalances. I'm rather suspect of the removal of OE rubber damping bushings in favor of the described much higher modulus plywood mounting scheme... Rubber mounts are provided with the intended purpose that minute dynamic vibrations are passively damped and not get transmitted nor harmonically amplified by steel frame components. During any of the previous work did it ever become necessary to "persuade" certain stuck components with an impact blow or an inadvertent drop of the hardware? Sometimes bearing raceways can manifest internal peening due to prior impact damage. Kindly let us know something more about the frequency of that vibration...

Frequency of vibration (this is only a guestimate as I'm not using any type of calibration device aside from my ear) is about every three to four revolutions of the wheels. If I free-run the motor, it functions smoothly with no vibration. Same if I leave the bottom wheel attached with the belt.

I had a little time to play with the top wheel. A small relief cut (partially drilled a hole in the upper wheel - only took a little off at a time and didn't have to drill all the way through) helped put that one in balance (doesn't stop at the same point every time when you spin). After putting it all back together, I still had the vibration.

I had to run out before I could get to the bottom wheel - hopefully I don't get back too late this evening so I can play with it a little, otherwise tomorrow.

[Steve Peterson]

My bandsaw had some vibration issues after replacing the tires. The wheels were unbalanced enough that they would oscillate back and forth at the same spot after removing the blade. I solved it by adding foil tape around the hubs near the top. A couple of hubs probably have around 10 wraps of tape. It runs great now, but may need to be repeated when I replace the tires.

Whichever

Steve

[John Kananis]

My bandsaw had some vibration issues after replacing the tires. The wheels were unbalanced enough that they would oscillate back and forth at the same spot after removing the blade. I solved it by adding foil tape around the hubs near the top. A couple of hubs probably have around 10 wraps of tape. It runs great now, but may need to be repeated when I replace the tires.

Whichever

Steve

This makes sense. After I swapped out the tires, it seems that I noticed a little more vibration.

[Allan Speers]

1: Are your tires perfectly round? Supposedly this can be an issue on some lower-priced machines.


2: You said your wheels are coplanar, but did you check just in the middle, or on the far left & right, with the table removed? On some saws, the top wheel can get out of alignment where one side is further forward than the other. Some saws even have an adjustment for this, but I think you have to pull the wheel to get to it.


3: Last thought: Remove your blade, lay it on the floor fully opened, and check for any kinks or bends.