Grinders

Barry Temple

Member
Messages
19
Location
London, Ontario, Canada
Hi all.

Is there a way to reverse the rotation on a grinder? I have a very old, small 6" grinder. The wheel spins up and away from me. I didn't really think about it until I was viewing Stuart's video on the grinding jig set up and realized his sparks appeared to be going down. Is it even worth trying to do it? I realize I can turn the thing around and use it that way but I'd have to remove the shields and I'd prefer for safety reasons not to do that. Up until a couple of weeks ago I used my sanding machine to sharpen because using the grinder freehand wasn't such a good thing. Then I saw a video on UTube demonstrating a jig for sharpening lathe tools. The fellow was selling the plans for it but I figured it out myself and built my own. It's similar to the Wolverine and works great except for the sparks shooting up in the air or the grit when I dressed the wheel. Thanks for all opinions.
 
Could you turn it around and switch the shields for one side to the other? I did on a old chinese one I had a few years ago that turned up. I just turned it around, took the wheels off, switched sides with the shields and walla it worked. Just a thought.
 
I did this to one of mine for sharpening carving tools. I just unbolted the base, turned it around and screwed it back together. The switch is still on the front but the wheels rotate away from me. The wheels for sharpening are 8" so I had to raise the grinder up for clearance and leave the shields off. If you aren't going to a bigger wheel, you should be able to switch the base and remount the shields.
 
Barry,

If the grinder has one of the old two-prong plugs, try unplugging and rotate the plug 180 degrees and plug it back in. If it has a three-prong plug or a two-prong that has one large and one small prong, then I expect that someone either replaced the cord or took it apart and accidently swapped two of the leads going to the motor or at the switch. It is running reverse phase to where it should be. One other possibility is to plug the grinder into another outlet. Occasionally an outlet can get wired out of phase.

Good luck.
 
Grinders typically have right hand and left hand threads on the arbores to keep the wheels from loosening up, much like on a table saw. If you reverse the rotation you could have a wheel/wheels come loose – not a pretty thought at 1700/3400RPM.
I’d shop for another grinder.
 
Excelent catch Bruce! :thumb:

Or another scary thought, maybe it's already running in reverse and you've been lucky that it hasn't loosened up. :eek: Someone correct me, but I think the standard grinder (where the wheels spin toward the user) has a rh threads on the right wheel and lh threads on the left wheel while facing the machine as if you were ready to grind. You could pull one of the grinding wheels and see if the shaft is reverse threaded from standard. If so, I would absolutely look for another grinder as per Bruce's advise. If it does have "standard" threads, only then would you want to do what is necessary to reverse the rotation of the motor. Also, if the threads are of the standard type make sure no one uses it until the rotation is corrected per the safety issue.
 
No one has asked but I will step in and ask, is it old enough that is is a dead man, thus it has a belt running to an electrical motor? If so, put a twist in the belt and it will run in reverse.
 
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