Balancing wheels of a budget grinder/ buying a balanced one

[Yorkshire Sam]

My budget bench grinder has started to vibrate terribly, I have tried it with the wheels off and there is no discernable vibration so its obviously the wheels. I dont use it a lot, just the occasional regrind of chisel ( mainly bench chisels with the odd carving one ) . I have stopped using it because of the dangers of the vibration I am told can make the wheels explode?

Can one buy balanced wheels without having to spend a fortune? What type of wheel would be best for the rare occasional use that I put it to? Or is there a workable alternative other than 'regrinding' with a diamond stone?

 

[wallace]

you need to dress the wheel whilst it is spinning. There are a couple of types of wheel dressers, a diamond one or a one that has little metal discs I think its called a granby type

 

[Phil Pascoe]

or a devil stone.

 

[sunnybob]

Is it bolted down?
If so have any bolts come loose?
with it running look at the outside edges of the wheels and see if you can see any movement.
The wheel would have to have a very severe indeed wobble to make it explode.

 

[CHJ]

My budget bench grinder has started to vibrate terribly, I have tried it with the wheels off and there is no discernable vibration so its obviously the wheels.

You would be safest getting the grinder looked at by someone who is conversant with the various grinding wheel parameters.

Having said that, if it was smooth running when first purchased (shout hooray with a budget grinder) there are several things that might have happened to start it vibrating.

1. The wheels may have moved from original location on spindle.
Slipped rotationally between clamping washers, or wheel bore material distorted (or poor in the first place) allowing slippage and off centre clamping. (heavy grinding loads or a bad catch)

2. One or both wheels have worn more in one area than another. (hardly likely but a thought )
Dressing the wheels to true them up may cure this if done correctly to remove just the high spots off the wheels.


Have you fitted the wheels individually, are both wheels vibrating.
Are the wheel bores a smooth sliding fit on the motor spindles or do they have lots of clearance.
Are your clamping washers just pressed steel as opposed to fully machined items, often the problem with 'side to side' alignment of wheels, can be overcome with tapered paper crush washers but takes patience and care.

With pressed steel washers that may be distorted there is no guarantee that they will clamp the wheel in the same alignment every time.

 

[Ttrees]

You need a dressing tool of some sort anyway, if its just chisels and plane irons you're grinding, as they get glazed from this process
and lead to overheating the steel.
I haven't bought one yet, so wondering if anyone has any other solutions?
Thanks
Tom

 

[Bm101]

I'd like to ask a question closely related to this without starting a whole new thread.... I set up my lidlaldi grinder with polishing mops a while back. The wheels are stage 1 and 2 if you like. Siasal and white close stitch. I had to enlarge the holes to 13mm but they are running out of true in a 'circumfrenential' manner? On the working surface not side to side.
( I know it's not a real word but it should be :wink: )
How do you dress these wheels to true?
Cheers
Chris

 

[GarF]

I had to shim mine using card and masking tape between the wheel and the paper 'washer' and was able to stop almost all the vibration without dressing away a substantial amount of the wheel. It might be worth trying this before 'turning' the wheels to round, as part of the vibration seems to come from the wheels not being perfectly perpendicular to the axis of the spindle.

There are a couple of tutorials about the web describing how to go about it. I'm afraid I can't remember which one I used. It only takes a beer mat or similar and a pencil.

CBN wheels are said to be dead straight.
Good luck
G

 

[ED65]

Or is there a workable alternative other than 'regrinding' with a diamond stone?

If it is just that they've worn out of true and it's the cost of a dresser that's putting you off they can be bought quite cheaply on AliExpress, although of course you might have a bit of wait getting the thing. But sometimes it's not too bad

 

[ED65]

How do you dress [cloth] wheels to true?

Carefully run against a coarse sanding drum held in electric drill maybe?

 

[Bm101]

Worth a try.

 

[Rorschach]

They will level out naturally over time though I must admit it is rare I come across an out of true fabric mop and I do use them a lot.
I would not recommend using anything friable as an abrasive to clean or true them, one stray bit of grit can ruin a good polish job.

 

[Phil Pascoe]

I trued a way off centre wet wheel by rigging up a block and clamping a devil stone down so it only just touched and then ran the wheel until it no longer made a sound. I then moved the devil again so it only just touched and repeated the process. I did this five or six times as it only just touched each time, and what was removed was very small. I suspect to have much success with a mop you would have to rig up something similar, as otherwise the abrasive or whatever you used would probably ride the wheel. You could probably stick a piece of 40 grit to a board - a decent paper shouldn't get broken down by cloth wheel, though you'd have to check it carefully. I doubt you'd be very successful with anything hand held.

 

[Simon_M]

You could try loosening a new wheel and rotating it by 90/180/270 and afterwards checking it again (might get lucky). An old wheel has it's eccentricity ironed out when it's diamond dressed (cleaned).

 

[Bm101]

Given me some ideas. Thanks guys as always.

 

[Inspector]

Oneway make a wheel balancing set that you can look into. They do work but you still need to true the wheels and over time will need to rebalance once in a while. http://www.leevalley.com/en/Wood/page.a ... at=1,43072

Cheapest wheel dresser is by finding a crew running road/concrete saws. If you ask nicely they may give you an old one. Cut it between the segments with an angle grinder or a plasma cutter. Put a handle on the pointy bit for safety. You can dress a lot before a segment has no more diamond so a sawblade will last a long time.

Put one wheel on the grinder and dress it until it round and true. Mark the position on the shaft with a Sharpie. Take it off and put the other wheel on the other side. Dress it. Put the first wheel back on using the alignment mark. Lightly dress both wheels again and you are done. It is a dusty operation so wear good PPE.

Pete

 

[Bm101]

Hot glue gun, scrap of mdf, old 40 grit pad.
Worked perfectly. Thanks Phil. Legend. Thanks all. Back on topic.

 

[Inspector]

Now that you have the wheels trued closer to round look for a buffing wheel rake to keep them clean.

Pete