Grinder Stands...Again

[Burt Alcantara]

I recently bought an 8x1x5/8 Ryobi 3600 rpm grinder. I replaced the 60 grit gray wheel with a WC 60 grit AO white. Running the grinder on my bench or on the floor produces a purring vibration, just like my big cat.

My first stand, from HF, was way too short so I returned it for their utility stand. When I installed the grinder with the Wolverine bases, there was a lot of vibration and excessive noise. In an attempt to lessen the vibration I screwed a 3/4 ply top over the existing top. No difference.

Then I bought a ShopFox stand from WC. Same problem. I did an eyeball rebalancing on both wheels but still got excessive vibration. I removed the grinder from the stand and tested it on the floor. Once again, the grinder just purred.

On the stand with the bases attached, vibration was all over the place. I tried adjusting the feet, weighing the stand with cider blocks, clamping 2x4s to the legs. All that happened was the vibration went from one side to the other.

Perhaps, the worst part is when I put the vari-grind into the pocket, I have to force the leg into the pocket to stop the vibration.

I don't know how to fix this. I'm considering building a massive stand using 2x4s doubled up. My bench is built this way and it is rock solid.

Do you have any ideas about eliminating the vibration from this stand? Suggestions for buying yet another stand?

Thanks,
Burt

[Mark Pruitt]

Burt, the vibration issue may be in the grinder itself. Two suggestions: (1) Dress the wheels. (2) If you've dressed the wheels and the problem persists, loosen the arbor nuts and rotate the wheels 90 degrees in one direction, retighten, and try again. You should eventually find a sweet spot where the vibration is minimal.

Another idea is to purchase the balancing system from OneWay, which gets rave reviews on this forum.

[Burt Alcantara]

Mark,
I tested the grinder with wheels on the floor, with one wheel and with no wheels. With no wheels, the grinder was silent. I had to touch the arbors to make sure it was running.

I'll admit there is the possibility that both wheels may not be completely aligned. For that reason, I'll probably go over to the local WC and pickup the wheel dressing jig.

I'd really don't want to buy or make another stand.

[John Hart]

Sounds to me like you have acheived the resonance frequency of the stand due to the height....Or maybe not. :confused:

Nevertheless, What if you take some of that shop floor matting stuff they have at home depot and cut out a little vibration dampener pad, the same footprint as the grinder, and mount it between the grinder and the benchtop surface. Rachet it down good and tight. It'll dissipate that vibration and noise so that it sounds like a cat again.:)

[Bruce Smith]

Sounds to me like you need a little heavier stand. I have fabricated a number of them in the folloing manner. Pay a visit to your local heavy
truck and see if they will let you look in their scrap metal dumpster. You no doubt will come across a discarded flywheel and they will often give it
to you or change you a buck or two as they usually sell the scrap to a metal salvage yard, salvage yard sometimes only pay a cent a pound if that. While you are there keep you eyes open for 3 or 4 foot length of
2 1/2" or 3 " schedule 80 steel pipe. If there is none to be had, try the local steel supplier or pipe shop and you will also need a couple of pipe
flanges. After determining the correct height the you want the grinder,
weld or thread the pipe flanges on too the pipe, bolt one end on the flywheel center and the other on a steel plate or a piece of 3/4" plywood and bolt the grinder to that. Myself I prefer the steel plate but the plywood will work. You should perhaps think about purchasing the Wolverine Sharpening system from Oneway as an out of balance grinding wheel could be introducing oscillations into the grinding stand. You would be surprised in the difference between a balanced and unbalanced grinding wheel. Good luck and please let us know how you make out. I would send a picture but there are too many picture police surfing the net these days.

[Gary DeWitt]

Some way to dress the wheels is an absolute must. If your tool bounces at all while sharpening, due to an out of round wheel, you will have a very hard time getting a sharp tool.
That said, when I bought my Delta grinder, it had a gray and a white wheel. After ensuring both were dressed to perfectly round, I was still getting enough vibration to wake the neighbors. The grinder without wheels was silent and smooth. It seems the wheels can be out of balance due to distribution of grit material in the matrix when they are made.
I replaced the wheels with Norton, and the vibration is now tolerable. Better quality wheels. If I were to balance them with the Oneway system, I think I could eliminate the vibration altogether.