Vibrating grinder returns

That's pretty much not true. I've experienced more than my share of wheels that got wet on one side only when surface grinding. Wheels are open enough to permit rapid transfer of solutions, so any water that enters a wheel is readily expelled on startup. Some grinders actually introduce coolant through the wheel. If the wheel is properly mounted, it won't shift when spooling up. Once up to speed, guaranteed------there won't be any water in the wheel.

Harold

Excellent post, Don. I expect his problem is flanges that are a slop fit on the shaft, or are not parallel.

Harold

If he's using the stamped steel POS spacers that ship with most grinders, that could be more than half the problem.

Some accurately machined ones would be a good start, and a benefit to all bench grinders not already equipped with them.

Cheers Trevor Jones

Yep! Couldn't have said it better myself.

Harold

Thanks, Harold! I'll try not to let it go to my head.

Much! :-)

Cheers Trevor Jones

The shaft is not bent. I did wonder about shipping damage, and tested it with a dial indicator. No runout.

The fixed flange washer was and is a worry. It has a depression right where the shoulder on the shaft rests, making the resting angle a bit vague. I flattened these flange washers up by hand, and added a machined and hardened little washer to extend the shoulder, but still.

I don't yet have the equipment to machine new flange washers. Can they be bought? I've looked, but without success.

Yes.

Right. I've tightened it by hand, by stalling both wheels with my body while I tightened the two nuts. It seems to work well enough now that I've trued the wheels. But if I loosen the wheels, I bet it'll be back to square one. And Norton makes pretty good wheels, so it's hard to believe that it's a problem with the wheels.

I think that this Ryobi grinder was a mistake, although it is proving to be educational, far too education. What I don't understand is why Ryobi doesn't have a better answer for the flange washers. This whole setup strikes me as the mechanical equivalent of using cheap thread and good cloth.

Joe Gwinn.

No way that free water will stay in there - Get it up to speed (3450 or better), and centrifugal force will see to that real quick. Start the Spin Cycle, you get a cold shower, and that water will be GONE.

There might be a slight residual imbalance effect if one side of the wheel is still damp and the other dry, but that should go away overnight if the wheel is kept in a dry environment.

-->--

Yes, everything turns. I was able to make progress by stalling both wheels with my body while I tightened the nuts.

The flange washers are pressed steel, and are a bit vague on alignment.

Yes.

The nut is not bottoming on the thread.

Yes.

I looked it up. The shafts are 5/8", just like the Ryobi.

New washers seem to have become the common thread. I don't have a lathe yet. Can one buy such washers?

Only about nine hours drive each way, in the Boston area. It is a pity.

Joe Gwinn

The wheels have been in the basement shop for months, and are quite dry.

Runout indicators are far smaller than lathes. I did check for runout with the wheels removed - there is none significant. I was theorizing that the unit had been dropped in shipment, bending the shaft. Didn't happen.

Not enough hours on this grinder yet to cause that problem.

I'm leaning to the bad-flange-washer theory. The Jet grinder - are its flange washers machined? If so, I could buy some "repair parts".

Joe Gwinn

According to Joseph Gwinn :

O.K. So there is some drag in the nut, apparently.

[ ... ]

O.K.

[ ... ]

O.K. But is it dragging, so it takes more torque to get it far enough even without the wheels present?

[ ... ]

We keep coming back to that.

[ ... ]

O.K.

[ ... ]

I don't know. Probably somewhere. If Harold doesn't know where, they probably can't be purchased. I'm glad to see him in this thread. He is *the* grinding expert on the newsgroup.

[ ... ]

Maybe someone else in the newsgroup is local to you and could take a look at it. Is there a local metalworking club? How local is NEMES?

Good Luck, DoN.

According to Joseph Gwinn :

Well ... if you lean on the wheel with a workpiece and stall the wheel (it needs to be that loose), and the motor keeps turning, you get abrasion on the shaft -- assuming no bushing in between them.

These are stamped -- but not bad enough to need replacing yet.

Good Luck, DoN.

My 6x18 surface grinder has provisions for spritzing coolant into the side of the wheel, where a flange makes sure it goes into the wheel, and is not flung off of the side.

Gunner

"I don't want to abolish government. I simply want to reduce it to the size where I can drag it into the bathroom and drown it in the bathtub.

-- Grover Norquist

I don't have a clue if there's anything available on the market. Damn, isn't there someone on the list that lives near you and owns a lathe that might be willing to give you a hand? I'd fix the damned thing myself, free, if it was in my possession. It's not a big deal---a couple hours and it would be up and running.

If you have a trip to Washington (State) planned in the near future, bring it along.

By virtue of what's happening, it's not the wheel. If the wheel was buggered, but the mounting was true, orientation wouldn't matter. Once trued, you could rotate it to any position with no unreasonable runout. It is normal to have the periphery run out a touch when the wheel has been disturbed----that's due to the small amount of clearance the locating boss should have with the wheel to prevent cracking the wheel. However, if a wheel gets trued in a wonky position, and is subsequently rotated on the arbor, the error has the potential to double. All depends on where it stops.

I'm a strong Norton fan, preferring their wheels to all others, but even they can turn out a bad one. I've seen one that wasn't parallel. Really hard to balance a wheel like that, and if you can't, there's no way in hell you can get it running without vibration aside from dressing away the thick side. No big deal----just annoying as hell.

Chuckle! Well, we pay for our education, whether it's a formal one or not.

I gather you don't have a lot of practical experience working with things like this. If not, it's hard to know what constitutes an adequate device, or if it will hold up well. No one can blame you for choosing what should be a respectable brand.

I think you already know why Ryobi has no answer. They don't want one. They sell things like that to unknowing people that settle for the problems at hand as if they are typical, and should be expected. As is so typical of industry today, they assume the buying public is totally ignorant or has a terrible memory, so they'll cut every corner possible to increase profits. In a nutshell, there is no room for a stamped flange, not unless it's thick enough to be machined after forming. Too much relies on that part of a grinder. Like your life.

I'm still using thee grinder I assembled back in '67. It's an old Craftsman 1/2 horse motor with shafts out each end, 3,450 RPM. I run a wet diamond wheel on the right hand side, and an aluminum oxide for HSS on the left. Mind you, I'm no stranger to such things----so it's not as if I'm an idiot that is satisfied with anything that comes down the pike, but I'm totally pleased with its performance. I think we can get you there eventually. Don't give up -----and see if you can find a guy that's willing to spend an hour or two on it for you.

Harold

Hell..nearly any of us would be proud to turn out a set of end washers. Id be happy to do so AND pay the postage.

Gunner

"I don't want to abolish government. I simply want to reduce it to the size where I can drag it into the bathroom and drown it in the bathtub.

-- Grover Norquist

It may not be that simple. In my mind's eye I can see shoulders that are badly screwed up from the stamped flanges not seating squarely. They may require attention so the flanges mate properly. That's why I suggested it would be best to have the grinder on hand. It really should be inspected-----it's entirely possible it was never square from the get-go. No sense spending time on a project to change, but not improve it. The other thing of importance is the shaft size. Not close---the real size, so the fixed flange will not add to the vibration.

Granted, the entire thing can be accomplished via mail-----with the grinder never leaving its location---but I wouldn't recommend that after all the trouble he's had.

Harold

There are "saw stiffeners" (arbor washers) sold for table saws that would work, I think. Here in Canada Lee Valley sells them, also Busy Bee, I would expect Woodworker's warehouse or some such in the states would be sources. 3

1/2 inch diameter, fits a 5/8" arbor, 1/4 " thick.

John

in Waltham, which is relatively local to Boston proper. to their show last year, and they're all a bunch of regular stand- up guys. Easiest way to get in touch might be to just show up for their May meeting.

I'd be willing to help, but I'm a bit of a hack, so I don't know how much of a help I'd be. :) The NEMES guys would probably be a better bet... --Glenn Lyford

Yes, I do know them. I sometimes go to their monthly meeting, and their Treasurer is a coworker of mine.

Joe Gwinn

The Baldor-style carbide tool grinders do much the same thing, feeding water to the inside of the wheel, and allowing it to trickle through. Runs in a haze of mist.

Joe Gwinn