Loose grinder wheel

[George Pagliarulo]

I’m trying to get my grinding wheels to run true but there is a lot of slop between the wheel bushings and the spindle. The wheel has plastic bushings. One that seems permanently attached and one that is a reducer. If I remember the measurements I took (always a problem ) the spindle OD is 5/8”, the wheel ID is 3/4” with the permanently attached bushing. Checked the spindle runout with a dial indicator and there non to speak of.
Are there aftermarket bushings available that can fix this?
Thanks.

 

[Brian Gustin]

Sure, you just need reducer bushings 3/4 to 5/8 seems to be a fairly common size, perhaps just needing to know what term to search for? should be able to find exactly what you need at McMaster-Carr , if you don't find them at a fastenall or on Amazon...

 

[hockenbery]

Are there aftermarket bushings available that can fix this?

Bushings may not be the problem so mulch as the wheel hole being a little off true.

You can shim the wheel to true. Vertical in 10 minutes or so.
The little round adhesive dots work well. Any sticky paper label will work.
Make reference marks on the spindle and the wheel so you keep the wheel in the same position on the spindle.

Run the grinder touch a pencil lightly to the side of the wheel. The short pencil arc is the out of true high point.
Draw a line with the pencil or visually from the center of the pencil arc to the center of the wheel.

Remove the wheel On the outside put a paper dot on the line so that it will be under the edge of the washer.
Put a paper dot on the inside across the center from the outside dot so it is under the edge of the washer.

Remount the wheel aligning the reference marks. The outside dot pushes that side of the wheel toward the motor the inside dot pushes that side of the wheel away from the motor. Turn the grinder on lightly touch the pencil to the side. The line will be a longer arc.
You want this arc to go at least 3/4 the way around.
Add paper dots on top of the first dots until you get a 3/4 line around the wheel.

This will get the wheel in vertical with the shaft. Dress the wheel surface to make it round.

 

[Richard Coers]

The center hole in all abrasive grinding wheels are cast in with a slight taper when they are made. There is little precision in that process. No bushing is permanently fixed. If you spend a bit more money to buy a Norton seeded gell wheel, you get a little more precision. But as Hockenbery said, they are all fixable for good runout. A diamond dresser is a necessity, but work great! Every grinding wheel from 6" to 36" are always trued up before being put to work. I watched crankshaft grinding wheels being put on in the factory at Caterpillar. Watching a 2" wide, 24" diameter wheel spin up for the first time is never done by standing close by.

 

[George Pagliarulo]

“Bushings may not be the problem so mulch as the wheel hole being a little off true.”
No, it is definitely the bushing. There is a lot of lateral movement on the spindle. I do have to dress the wheel to get it truly round but I don’t want to do that until I fix the bushing issue and adjust it to get rid of the lateral movement.

“Sure, you just need reducer bushings 3/4 to 5/8 seems to be a fairly common size”
Thanks, I figured there had to be reducers, just didn’t know what to call them. All the reducers I found were for plumbing.
Tractor Supply has them in stock. I just need to take of 1/8” since they come 1-1/8” long not 1”, the width of the wheels.

 

[Marc Banka]

The washers on each face of the wheel can be a real problem. They’re usually stamped steel and easily deform when you tighten the wheel. Makes it nearly impossible to get the wheel to run true. Woodturners wonders sells a washer set up, a heavy machined washer behind and a two piece spherical washer set for the outside.
The plastic bushings aren’t super close fit, but once the wheel is clamped in place, don’t pose a problem. Unless yours are just wrong. If they came with the wheel they should be ok.

 

[George Pagliarulo]

It is a Baldor grinder and the internal and external flanges are pretty substantial. To adjust the wheel I tighten the outside flange, and check the lateral wobble. Then loosen and tun the flange to find the best position. I can get it to run pretty true but still have some wobble, maybe 1/16” from side to side.
Does the side of a new wheel need to be dressed like the face of the wheel?
I don’t know what is a lot and what is just the wheel needing to be dressed.

 

[Leo Van Der Loo]

I’m trying to get my grinding wheels to run true but there is a lot of slop between the wheel bushings and the spindle. The wheel has plastic bushings. One that seems permanently attached and one that is a reducer. If I remember the measurements I took (always a problem ) the spindle OD is 5/8”, the wheel ID is 3/4” with the permanently attached bushing. Checked the spindle runout with a dial indicator and there non to speak of.
Are there aftermarket bushings available that can fix this?
Thanks.

George many grinder wheels nowadays do come with several bushings that will get you to fit the wheel without slop, years ago wheels often had lead bushings in them, and you would order the wheel for the spindle size you had on the grinder, to get around the need to have all the different sized wheel openings they came out with the loose bushings, often 4 or 5 sizes that you could make to fit the grinder shaft.

And yes you can order bushings to fit nicely in the wheel and on the spindle/shaft, some wheels stil have a permanent layer inside the wheel opening to have the opening concentric to the wheel.

Also industrial wheels have very often much larger openings in the wheels and have special reducers.

from Amazon.

I would expect the Baldor grinder flanges to be machined and tight fitting on the shaft, of course your wheel could be warped and then you should bring the wheel back for a good wheel, I do expect that with the right bushings this wobble to be eliminated, and yes rotating the wheel to find the best position could be needed, (should not be needed with good flanges though).

 

[hockenbery]

Does the side of a new wheel need to be dressed like the face of the wheel

No. That will likely damage the wheel and you have no way to dress the inside face which is eaqally off true

You need to shim the wheel to get it perpendicular. To the shaft.

It will take about 10 minutes.
I described that earlier.


You can shim the wheel to true. Vertical in 10 minutes or so.
The little round adhesive dots work well. Any sticky paper label will work.
Make reference marks on the spindle and the wheel so you keep the wheel in the same position on the spindle.

Run the grinder touch a pencil lightly to the side of the wheel. The short pencil arc is the out of true high point.
Draw a line with the pencil or visually from the center of the pencil arc to the center of the wheel.

Remove the wheel On the outside put a paper dot on the line so that it will be under the edge of the washer.
Put a paper dot on the inside across the center from the outside dot so it is under the edge of the washer.

Remount the wheel aligning the reference marks. The outside dot pushes that side of the wheel toward the motor the inside dot pushes that side of the wheel away from the motor. Turn the grinder on lightly touch the pencil to the side. The line will be a longer arc.
You want this arc to go at least 3/4 the way around.
Add paper dots on top of the first dots until you get a 3/4 line around the wheel.

This will get the wheel in vertical with the shaft. Dress the wheel surface to make it round.

 

[hockenbery]

Does the side of a new wheel need to be dressed like the face of the wheel?

No. You may ruin the wheel or hurt yourself

Here is Don Geigers method- article is in the December 2016 AAW journal.
PDF below

 

[robo hippy]

Well, the first 1 hp Rikon grinder I got had a wheel so out of whack that I would not give it to some one I didn't like. I did read a long time ago that the plastic bushings are junk, and I agree. Some times the nuts can be off as well, though with a Baldor grinder, that is generally less of a problem. This is why Woodturner's Wonders sells the 'helical' washers, one concave, one convex so that when you tighten, they seat perfectly. With my Baldor, it has a 3/4 inch shaft. With a very light touch, you can true up the sides of a standard grinding wheel. There is a risk of them fracturing since they are not made for sideways pressures. Stand out of the line of fire, and wear a face shield. You need to mark out where the wheel sits on the axle so that if/when you take the wheel off, you can put it back on in the exact same place. Again, this is less of a problem with the Baldor grinders than others.

robo hippy

 

[Doug Rasmussen]

Most recommendations regarding bench grinders and grinding wheel truing/dressing on this forum tend towards buying on price rather than quality. This is in contrast to the careful analysis given to the purchasing of lathes, cutting tools, sharpening fixtures, threading jigs, etc, etc. It seems to be part of human nature, when we aren't knowledgeable we buy on price.

Talking about a grinding wheel with a 1/16" wobble. That likely is not a quality setup whether the problem is the wheel or the grinder itself or both. All the fixes on earth are not going to turn junk into quality. Quality is expensive. Rikon grinders and cheap wheels don't come under the definition of quality IMO.


Wheel dressing even with the best of equipment can be tricky. I have a couple devices similar to the pictured Geiger dresser. These provide a guided path on the tool rest, not depending on hand guidance, and a fine infeed of the dressing diamond. The diamond's angular orientation to the wheel's face is also accounted for.