View Full Version : bench grinder questions.

09-19-2017, 02:12 AM
I scored two nice bench grinders at an auction for $45. When I turned them on one was very well balanced and the other danced on the table.
When I took the wheels of the vibration is gone.
Can a wheel be dressed on its sides to try to get it to run true.?
Also I use a diamond dressing stick Its one diamond in the end of a piece of round bar. I battle to get a smooth transition.What are those star type dressers like.
Also is there an optimum height for a pedestal,or just what feels good for you.

Paul Alciatore
09-19-2017, 02:52 AM
Generally wheels are dressed on the face, not on the sides. But I see no problem with dressing the sides if it is done in the manner of a facing cut on a lathe.

That being said, it would be a very poor wheel that would need dressing on the side. If dressing on the face does not produce a good balance, I would just get a new wheel.

I have also seen people who actually drill holes in a wheel to achieve a better balance. I would not recommend that as there is no way to know if you have introduced some small cracks that could increase in size, ultimately leading to catastrophic failure. Do not do that. As I said, get a new wheel.

09-19-2017, 03:13 AM

09-19-2017, 04:35 AM
Yeah, id rather just buy a new wheel before messing about trying to dress the sides. You dont want to mess around with something that can explode when provoked in movement, better safe than sorry

09-19-2017, 11:12 AM
Fwiw, be wary of unknown wheels on used grinders. You don't know if they were abused at some point (dropped, cracked, etc), and then installed on the grinder just to make the grinder appear more suitable for sale.

I have read many times that grinding on the side of a grinder wheel can lead to failures. If the sides need dressing, it sounds like they should be retired.

09-19-2017, 11:12 AM
Before you start dressing anything, check the interface between the motor shaft and the wheel to make sure the wheel mounts properly.

09-19-2017, 12:27 PM
you don't know these grinders or wheels, so i'd be cautious. However if you are convinced the wheel is good, statically balance it - level knife edges and an arbor is the ideal set up. With a dressing stick, held a just a few degrees off of parallel with the side the wheel, take a bit of the heavy side, retry on the balancer and so on.

grinding on the side is fine, if you are careful about it very light forces etc. removing material by dressing the side is also fine and not uncommon in tool rooms. Its one of the black and white rules in a grey world - since we can't define or depend on common sense reigning, just issue the deny verdict.

Bob La Londe
09-19-2017, 12:32 PM
It may still have bad runout but without the mass of the wheel it just doesn't bounce as much.

09-19-2017, 01:34 PM
Tool and Diemakers dress the sides of wheels all the time. Mostly because we need to sidewheel grind a slot or something like it. After dressing the wheel on both sides using a diamond almost like a toolbit when facing as said before, we than undercut the side to be used leaving just a small rim approx. 1/16". Loosen the wheel nut and turn the wheel 1/4-1/2 turn. Tighten. Last - dress the bottom.
In your case - buy a new wheel! The old wheel will be soaked with oil in the bottom half because most likely it has not turned for years.
It could also be damaged.

J Tiers
09-19-2017, 03:17 PM
Toss old wheels unless they ring clearly.

Oil in the wheel should damp the ring, but may not. If it has an extra heavy "side", toss it, most likely it does haveoil in it, maybe even coolant, nobody says it had to be from that grinder, as mentioned, might be mounted just to sell the thing.

Might not even have the right bushing in it. See if the bushing (if any) fits the wheel and spindle well. Not tight, not too loose.

Alistair Hosie
09-19-2017, 03:47 PM
I have, when dressing anything, do front and sides . I am sure this comes from my years of bowl turning. Also there is a chance that new wheels from chindia will be sold unbalanced. My experience, and will still maybe need dressing. Alistair

09-20-2017, 02:37 AM
..there is a chance that new wheels from chindia will be sold unbalanced..

Easy there. Your term 'chindia' sounds a bit pejorative. Anyway, I have good wheels from Norton, Radiac and the like that weren't perfectly balanced when new.


09-20-2017, 09:37 AM
Easy there. Your term 'chindia' sounds a bit pejorative.

some PC sense now says we can't be pejorative? There is nothing wrong with having a disparaging or negative bias from stuff made in those or whatever countries, although I acknowledge holding the view doesn't mean its always 100% accurate or can't change over time.

09-20-2017, 10:49 AM
Check your grinder shafts to be sure they are true. If good get new wheels with bushings that fit and then see how it runs. That should help your problem.

Bob La Londe
09-20-2017, 11:20 AM
I recently mounted some new brushes I wasn't happy with. As light as they are... I made new good fitting bushings out of aluminum on the lathe and all was good in the world. Since I made one piece backer plates and bushings it allowed me to space the brushes exactly where I wanted them as well.

09-20-2017, 11:27 AM

Above is a fairly good piece on tuning a grinder by Keith Fenner.

no neat sig line