Grizzly Oscillating Spindle Sander Noise

[mrmortise]

Dear Group, Last summer, I purchased the Grizzly G9922 Oscillating Spindle Sander. All seems kosher except, to my ears, it makes the worst undulating grinding noise. I can't really describe it except that sounds like a low growl. I called tech support and was told to take it all apart and strip everything off down to the motor and run it. If it still makes a horrible noise, they will send a new motor. After doing so,it didn't seem too much different. A little less reverbatory, but still I get the feeling it isn't supposed to sound this way! The problem I'm having, of course, is that I really don't know what these machines are supposed to sound like. The machine seems to work fine, but I want to be sure there is nothing wrong. Are Spindle Sanders inherently unpleasant in their sonorous attributes. Is the Grizzly G9922 prone to noise problems. How can I really tell if I have a bearing problem or not? Thanks for your observations! Thank You, Michael

[Al in WA]

[Sam Wheeler]

Mine makes very little noise and definitely nothing resembling grinding.

[JGS]

[Bill Waller]

Michael, I have the same machine, and yes, mine makes a lot of noise. I think that the sound generated by the mechanism that moves the spindle up and down is amplified by the sheet metal cabinet. Of course, the shape of the cabinet does not help with the noise. It is kind of like a big megaphone. :-)

Bill Waller New Eagle, PA

[e-mail]

[Larry Jaques]

On 22 Oct 2004 17:58:15 -0700, [e-mail] (mrmortise) calmly ranted:

If you get any noise at all with just the motor, it's probably bad motor bearings. How much play is in the spindle itself? If the bearings in that are bad, it would multiply.

I haven't heard a G9922, but my Griz G1012 bandsaw sung and vibrated a bit before I installed the link belt. I found a couple in the local HF store for $17 each and grabbed them.

[Larry Jaques]

On Sat, 23 Oct 2004 08:30:18 -0400, Bill Waller calmly ranted:

Sheetmetal issues can be handled quickly and easily with an application of a sound deadener sheet. I watched the guys at the body shop install them on door panels and asked what they were. It's made with a rubbery glue attached to a 4x6 sheet of aluminum which is simply stuck onto the center of the sheetmetal panel. The rubbery glue absorbs the noise.

Link belts also remove a lot of the noise associated with power conveyance. Do that first, then see how much noise is left and go from there. (Oops, not on this model, but for all other belt- driven machinery.)

[Andy Dingley]

Aluminium ? Usually lead, when I've used them. Cars are generally just plain rubber, which stops the panel "drumming". If you're trying to stop noise being transmitted through the panel (like a boat engine room bulkhead, or a machine case, then a rubbery isolator and a _heavy_ stiff sheet are more effective. I'd expect aluminium to be too light to really be much use, if you weren't being really weight-conscious.

You can make your own pretty easily. Roofing lead sheet and a layer of something thick and rubbery, like windowframe mastic.

[Larry Jaques]

On Sat, 23 Oct 2004 15:39:10 +0100, Andy Dingley calmly ranted:

We're weight conscious on this side of the pond, Sir.

I believe it's simply an inexpensive carrier for the main ingredient, the gluey pad.

Yes, plastic roofing cement might work, but it may harden too much. This stuff stayed pliable so it continues to absorb vibes.

[George]

BELT?

able to move the motor shaft forward or aft with hand pressure? Can you do the mechanic's trick of placing a screwdriver point on the bearing case and putting the handle to your ear? Bearings rumble, and when bad, heat.

You can check that oscillation mechanism to an extent by checking vertical travel of the drum with power removed. Worn worm gearing will give a greater range of movement than the merely perceptible which it should have. If you stop it in a few different positions and change, you may catch a bad tooth by differences.

Runout on the drum would be a clear indication of problems with the spindle bearings.

Does anyone look before they answer?

[RonB]

Michael: Not too clear on what happed with the noise when you tore down. Did it still make noise with motor only or after assembly?

Reason I ask is I have a the smaller Jet JBOS-5 for a couple of years and it is a very quiet machine. However this summer, it seemed to take on a different sound - a slight growling vibration. When I lifted it off of it's table I just happened to see a TINY setscrew on the tabletop. I dug out the parts diagram, searched for setscrews, and located one missing from the mechanism that moves the spindle up and down. This screw secured one of two eccentric levers, one on each side of the spindle shaft, to a separate rotating shaft. The loose lever was grabbing and shaking as the other moved the mechanism up and down. This small vibration was amplified through the sander and table.

I suspect all of these mechanisms are similar. Might look for loose setscrews, etc.