Wobbly Grinding Wheel?

I interpret "wobble" to be a left to right and back again. Dressing won't help this, of course. Bounce, it might. If there's no runout at the end of the shaft, then your grinder is till sound.

I think your culprit is at the center of the wheel. Turn some wooden bushings and try them out instead of the factory types. Do an inspection for damage to the stone while you're at it.

If the washers were thick enough and tight enough to self-align, they might help. As it is, they're just there to grip the wheel.

If you switch the wheels, you can easily find out whether the problem is the wheel or the grinder. Then you go from there.

Bill

Harry Curley wrote:

Hi Harry

You, I and a lot of others have, or have had this problem, so much so that Oneway has made the precision balancing system, I find it rather expensive, but it does a excellent job.

The problem has arisen because the flanges that hold on the wheels are now stamped out of a steel plate, rather than machined, as was done before and still for the higher priced machines.

If you are able to machine the flanges or have it done, or have someone make new ones, the wobble is almost guaranteed to be gone, if there is uneven weight within the stone itself, (you only notice that by vibration), you need a balancing system, like the Oneway, it has machined flanges for 2 wheels and weights, however in order for the system to slide on your grinders shaft and in your wheel you do need a stone whit a large hole. I hope that this helps you, if I have not been clear enough, don't hesitate to ask for a more or better explanation.

I have a two 8" grinding wheels-grinder for sharping my turning tools. The one wheel is wobbling quite abit and the other one does not. I have removed the wobbling wheel and there does not appear to be a damage to the shaft or the serrated bushing holding the wheel onto the shaft. There are two large metals discs one of the inside of wheel and one on the outside of the wheel behind the nut that holds the wheel onto the shaft, There doesn't appear any excessive wear on the center of the grinding wheel attached to the shaft. This condition just started recently. When purchased(3 years ago) both wheels ran true Any suggestions?

there is a cheap solution - get a discarded diamond saw blade and use it to true the blade (including the sides - I couldn't find a discarded one, so I bought a small blade at HF for about $4 - works fine for occasional use

Bill

to contact me, do not reply to this message, instead correct this address and use it

will iam_ b_ No ble at msn daught com

Anyone can lap a stamped washer if they care to. If the sides of the stone are not straight, won't do a bit of good. Matter of fact, won't do a bit of good or harm if the washers are stamped, because the stone doesn't flex, and the hole is neither small enough nor the washer thick enough to align the stone. It would also need ground threads like those on your tablesaw arbor, of course, to be effective. Alignment is the job of the insert - bushing - which is often made of flexible material like plastic and can deform and stay that way if bumped.

Matter of fact, though you can spend as much as you want for a "balancing" system, a bit of sheet lead held firmly by those washers against the appropriate portion of the wheel does a wonderful job. Put cardboard where lead's not required but shimming might be if your washers are bored and lapped so precisely as to require it. Balance is an entirely different matter from alignment, only being affected if the wheel is severely off-center.

I have learned that even when replacing the insert - bushing and washers the outer circle of the grinding wheel was out of round and need it to be trued. I have had wobbling and out of round problems with wheel made in the middle east and had to returned them to the industrial supplier. At the end of the day I invested in a diamond wheel dresser. I have found that the insert - bushings are made with stamped metal and plastic and the ID and OD are not concentrically.

If the old bushing was out of round, of course. Couldn't be otherwise. Actually, if the old one was perfect and the new one isn't, same pertains.

When I bought my mandrel, it came with the standard wheels of the day and some wonderful soft metal (may have been lead, but I'm not telling) bushings. You could adjust/tighten them with a punch. When new wheels were installed, first thing I did was put in the old bushings, though the new appear to be of a polyethylene-type plastic which might also be adjustable with a punch. .

thanks, Bill.. I was going to suggest that but it sounded too easy... sometimes we look for the complex answers first.. *g*

Mac

Make sure you switch _with_ the bushings, or it doesn't work.

Hi George

If you want to shim your grinder stone with lead and cardboard and adjust/tighten with a punch, you go right ahead. I would certainly not advice anyone to go and do that. A properly machined flange that fits the grinder shaft, and at 90 degrees to the shaft, will keep the wheel at 90 degrees and the stone will not wobble, if there is a twist in the wheel you better get another stone. The bushings used to be lead and this meant more inventory for different shaft sizes, and that is the reason they now (mostly) use layered plastic bushings (fit all) just to center the wheel on the shaft and than the wheel should be trued up. For imbalances of the wheel itself you should use a balancing system or get another stone.

Have fun and take care Leo Van Der Loo

Probably because you've got one of those expensive methods?

HOGWASH! The stone will not deform no matter the pressure of the washer, which is why it is completely unimportant to have lapped faces. A bad stone will be a bad stone, and no washer will make it otherwise. OTOH, if the washer is flexible, it can make some minor adjustments as the nut is tightened to conform to the surface of the stone. This can be a great asset in fiddling the stone to concentricity.

That's what weighting the high side with lead does. Well said.

Hi George

Can you not read ??

The flanges WILL keep the stone at 90 degrees to the shaft, if they are machined to size and to fit on the shaft at 90 degrees, I did NOT say anything about deforming the stone, I did say if the stone has a twist in itself, with other words, the stone is defective in its form, than get an other stone. I have changed enough grinder stones and even machined flanges in my live to know what the common problems are and how to tune the grinders, so just read and learn.