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View Full Version : Grinder 'pulling'



Patrick Bernardo
11-24-2013, 1:51 PM
I got lucky and bought an older Baldor grinder off of CL for cheap. It runs fine, no vibration, no overheating, nothing. However, when I put a grinding wheel on the right side of the grinder (my right as I face the grinder), it pulls toward me, as if the entire grinder was trying to spin clockwise. I have brass bearings, which I bought from Sears. If I put the same wheel on the left side, it runs fine. No vibration, no pulling.

Does this pulling on the one side indicate a problem of some sort? I don't have the tools to measure runout on the arbor, but it doesn't look bent. If I turn it slowly, it doesn't seemto be 'wobbly,' but of course I'm just eyeing it up.

Nothing I've read anywhere on the net talks about this problem, so I'm just not sure what it means. It's not terrible, as I probably will only use the one side for grinding anyway, but I'd like to have the option of having another grit wheel, or a wire brush, on the other side.

Jacob Reverb
11-24-2013, 2:40 PM
Do all grinders do that, as a result of precession?

I seem to recall that one of my grinders somehow tried to move, but I forget exactly how. All my grinders now are fastened down, so I can't check.

Jim Koepke
11-24-2013, 4:54 PM
Does this pulling on the one side indicate a problem of some sort? I don't have the tools to measure runout on the arbor, but it doesn't look bent.

You may not be able to measure the runout, but you are likely able to detect runout. A block of wood with a screw sticking out under the arbor can reveal runout.

Actually there are many variations of hardware one could use for this.

Set the screw to just before it touches the arbor and then spin slowly by hand. Watch the gap between the screw and the arbor. This may take a few times of adjusting the makeshift "gauge."

jtk

Winton Applegate
11-24-2013, 5:39 PM
Two things :
1. Is your grinder bolted or clamped down ? Never use a grinder that isn't . If you get a shirt sleeve caught in it it will crawl up your arm and . . . well you get the picture. If bolted you might have a chance to tear yourself free. Probably not . . .

2. Look at ALL of this video. Turning direction of wheel determines direction of rotation around a vertical axis for the unit.
http://www.youtube.com/watch?v=LrTw7EdyW9A

george wilson
11-24-2013, 5:39 PM
I haven't had this happen. Possibly some kind of gyroscopic effect? Fasten it down. Grinders can be just as dangerous as any other machine. I saw a picture of the same model flat face 1960's Craftsman grinder I have. Some guy with long hair got caught in a wire brush wheel. The grinder yanked his head into the end bell so fast that the whole die cast housing was broken to pieces with his FACE. A big hunk of scalp was gone,too.

So,don't let your grinder move about when you are trying to use it!! Even a 1/3 H.P. grinder can do significant damage.(Well,in the 60's 1/3 H.P. actually came closer to being the actual H.P. than it is now!!)

Patrick Bernardo
11-24-2013, 5:40 PM
Jim, great idea! Thanks - I never thought of that. I'll give it a try.

Jacob, it really pulls hard. This is the first power grinder I've owned, but my impression is that this can't be a feature.

Patrick Bernardo
11-24-2013, 5:42 PM
Yes, bolted down now. I noticed the rotation of the grinder when I was testing it out. It pulls hard enough that I'm mildly worried that it could shear a bolt. The grinder was slotted big enough to only allow a 5/16 bolt.

Winton Applegate
11-24-2013, 5:43 PM
Put BOTH wheels on it to cancel out the effect !

Patrick Bernardo
11-24-2013, 5:46 PM
Winton - with a wheel on the left, and any wheel on the right, it pulls. I experimented with a bunch of configurations (I have a couple of wheels from a hand grinder, plus one that came with the grinder). I bought a wire brush after I bolted it down, but it wouldn't be a problem to unbolt it and try with the wire wheel.

Edited to correct the misspelled name. I must have been channeling 1984...

lowell holmes
11-24-2013, 5:49 PM
If there is a collection of safety oriented posts, George's should be in it.

Winton Applegate
11-24-2013, 5:53 PM
Pulls with both wheels. I experimented with a bunch of configurations

This isn't good ! ! !
It means your grinder is possessed by a demon. Possibly THE KEYMASTER him self.
I would call THE GHOST BUSTERS
DO IT NOW ! Before all is lost.