Preventing Bench Grinder Lateral Wobble Question

[A&P mechanic]

Good afternoon guys,

I have a question regarding the wobble on my bench grinder and was looking for any suggestions or advice to reduce the wobble.

Specifically, it is a lateral wobble from left to right. My bench grinder is made in Taiwan and is a Dayton. The wheels are American made and are made of cardboard. The wheels are for sharpening-chisels/axe/knife etc. The grinder shaft is 3/4”. The wheels had a removable plastic insert that was 5/8”, once the plastic 5/8” insert is removed the wheel fits on my 3/4” grinder shaft. I have three bench grinders that all have different shafts. A Baldor for polishing, a Chinese Craftsman-wire wheel/stone (I liked the variable speed even though it’s Chinese) and this Dayton which I will only be using for sharpening.

Overall, my question is: I would like to reduce or if possible eliminate the left and right wobble on the wheels. When the grinder is off and I spin the wheels by hand I can clearly see them tilting left and right. I have the wheels on tight.

I did a search function and read through several posts. Essentially what I read from previous posts was, the wheels that do have a plastic insert-the insert is not perfect and needs to be replaced with a aftermarket insert. I did not see any posts about this particular issue.

Thanks in advance!

 

[drivesitfar]

AP: i'm not sure what the fix is for your issue since i don't use those wheels on my grinders (yet). i can tell you that the members that follow the Craftsman block grinder thread know quite a bit about grinders so you might post that question over there instead of starting a thread that might get lost quickly. here's the link.

http://www.garagejournal.com/forum/showthread.php?t=157794

i'm guessing the fix is either the metal inserts or tightening up the wheels if you haven't tried that already.

it doesn't look like you have the Dayton bench grinder bolted down which might make a difference and might i suggest getting some rubber feet that the bolts go through to give the grinder a little give while its spinning? those rubber feet are what a lot of members use under their Craftsman block bench grinders so the same ones at Lowe's might work for your little Dayton.

good luck

 

[DocsMachine]

I had a similar issue with a Baldor bench grinder- despite repeated truing, I still got a vibration, when I eventually traced to the wheel wobbling side-to-side.

Here's a quick write up of what I did to cure it- basically both the wheel spacers/washers and the nuts needed to be trued up square. Made a huge difference for me.

Doc.

 

[abk241]

When you say wobble...are you meaning the motor shaft is sliding to the left and right?

I see some loose (not seated) cap screws on both end caps.
Has someone opened this motor up and perhaps left out some spacers or thrust washers?

 

[rlitman]

The nuts and washers hold the wheel. The insert just keeps the wheel centered until it is tightened in. After that, it's all on the washers. If they're off, then that's your problem.

Are the wheel's faces parallel to each other? If no, then there's your wobble. If yes, then the wheel isn't the issue.

As for radial runout, that's easily fixed with a diamond dresser.

 

[Nor'Easter]

What are you sharpening with the grinders?

 

[larry_g]

In addition to Doc's write up here is another fix. It shows how to indicate some of the surfaces that you should check.

If I remember there are 3 or 4 parts to this vid.

lg
no neat sig line

 

[A&P mechanic]

Drive-I do actually have the grinder bolted down. The wheels are fairly tight, tight enough to put a small imprint into the cardboard wheels. The grinder has three of the four original rubber feet underneath it. I bought the grinder used so that is why the 4th rubber foot is missing. I will go ahead and replace the rubber feat next time I go to the hardware store. That “little” 1 hp Dayton has a shipping weight of 110 pounds according to grainger. I appreciate the advice with the Craftsman thread; I will read through it before making a decision to post in it.

This is a newer model of a similar 1hp Dayton. http://www.grainger.com/product/DAYTON-Bench-Grinder-2LKT2?functionCode=P2IDP2PCP The model numbers are different, both are 1 hp. Mine is older, I have all the pieces but took them off for sharpening.

Doc-That write up was very informative. I plan on getting a mill and lathe eventually, when I do. I will most likely true the washers and nuts. (I do not have spacers, but could add them if you think they are necessary?) That refinished Baldor looks great.

Abk-I am referring to the wheel tilting left and right. Specifically it appears to not always be a perfect 90 degrees. When spinning it by hand, I can clearly see the wheel sway left and right. The cap screws held all the original pieces-wheel guards etc. The cap screws are tight; I left them in there instead of storing them with the other pieces as shown in the link. You can see all pieces I have with the grinder in the original link.
The manufacturer of the sharpening wheels says-if you have an 8inch grinder, use 10inch wheels. (I realize this is backwards but there is good reason when sharpening) The reason is if you are sharpening-say a lawn mower blade then the blade will not hit the bench grinder.

Rlit-The wheel faces appear to be facing each other. There is no insert because the grinder shaft is the same size as the wheel opening. Both are 3/4”. I have dressed my wheels occasionally but will not be dressing these as they are cardboard. The radial run out appears fine. I am not sure what a thrust washer is. I do not suspect the previous owner ever disassembling the grinder. I bought it from a older gentlemen who used it for hobby work in his garage.

Easter-I am sharpening chisels, a hatchet, and some old knives. I sharpen drill bits on a regular stone wheel.

Larry-When I click the link it says “this video does not exist”

I think Doc may be on to something. That makes perfect sense regarding the nuts and cup type spacer not being true. (I do not have washers but could add them; it appears they may not be necessary on this set up?) I realize I could order a left hand threaded nut and get the normal RH thread through a hardware store and that would be truer.

Appreciate the replies, learned a few things today. I suspect the nuts and spacers are not true. I will true them in future when I get a milling machine and lathe. Thanks guys!

 

[Fretters]

If you search Keith Fenner's videos on Youtube, he did a vid or two on the issue with a new bench grinder he bought. Same type of issue as Doc mentioned.

 

[larry_g]

If you search Keith Fenner's videos on Youtube, he did a vid or two on the issue with a new bench grinder he bought. Same type of issue as Doc mentioned.

I corrected the link in my post above, it is to the video that Keith Fenner does.

This is the same link

 

[exmaxima1]

Drive-I do actually have the grinder bolted down. The wheels are fairly tight, tight enough to put a small imprint into the cardboard wheels. The grinder has three of the four original rubber feet underneath it. I bought the grinder used so that is why the 4th rubber foot is missing. I will go ahead and replace the rubber feat next time I go to the hardware store. That “little” 1 hp Dayton has a shipping weight of 110 pounds according to grainger. I appreciate the advice with the Craftsman thread; I will read through it before making a decision to post in it.

This is a newer model of a similar 1hp Dayton. http://www.grainger.com/product/DAYTON-Bench-Grinder-2LKT2?functionCode=P2IDP2PCP The model numbers are different, both are 1 hp. Mine is older, I have all the pieces but took them off for sharpening.

The newer Dayton you linked is a much bigger model than yours. I have that model, though a bit older as it draws 13 amps, and it is indeed a beast. The motor is 7.5" diameter, which is bigger than your 56 Frame, and it has 1" shafts. It probably weighs close to 100 lbs, maybe twice as much as your old version. BTW, I'm not sure your grinder was made in Taiwan---does it read "Taiwan" anywhere on it? I suspect it is a USA-made Doerr model.

That aside, I've tried those cardboard wheels and they spin extremely true. I had them on a 1/3 hp Doerr grinder, spinning at 3450 revs, and they worked ok. I didn't care for the grit coated wheel at all (pain to dress it, and not really suitable for much of anything), but the slotted wheel with the compund worked pretty decent. I ultimately sold the kit off when I discovered the leather strops that run on belt sanders---fastest way to put a polished convex edge on a knife blade, especially hard steels like ZDP-189.

 

[abk241]

Looking at pics 4 & 5 in post # 8...are those jack screws?

 

[lametec]

Looking at pics 4 & 5 in post # 8...are those jack screws?

For holding the (missing) guards in place.