Problems with Makita 4.5" angle grinder

[md21722]

I got a Makita 4.5" angle grinder with the paddle switch about 2 months ago. I find it vibrates enough with a depressed cutoff wheel that my hands get tingly and if I use it with a coarse grinding disc I can start to feel it up my forearms. It doesn't get very hot, just warm and it doesn't vibrate as much when its not cutting or grinding. Is this pretty normal in this class or is there something wrong with the new grinder? I have used industrial pneumatic grade grinders that are butter smooth.

 

[dodge610]

Are you using quality grind wheels. If not the grind wheel could be out of balance they are mass produced on an assembly line. Could of got a few from a bad run.

 

[md21722]

I've been using the Makita grinding wheel that came with the grinder, NAPA coarse grit grinding wheels, and Diablo cutoff wheels. Taking a disc that vibrates on the Makita and putting it on the industrial pneumatic and the problem goes away. So the question for me is, is the particular grinder I've got out of balance or is it just common in the sub $100 class of grinders.

 

[LG63]

What model? Sounds like a defective unit, I've never had vibration problems with even the low end Makita's.

 

[General Geoff]

I've been using the Makita grinding wheel that came with the grinder, NAPA coarse grit grinding wheels, and Diablo cutoff wheels. Taking a disc that vibrates on the Makita and putting it on the industrial pneumatic and the problem goes away. So the question for me is, is the particular grinder I've got out of balance or is it just common in the sub $100 class of grinders.

Sounds like something's out of balance in the grinder itself. Does it vibrate when no disc is mounted?

 

[md21722]

It's a Makita 9557PB - 4.5" 7.5A paddle switch. No noticeable problems with no disc mounted or with a disc mounted not touching metal. Only when doing work. I suppose the Makita vibrates more than the industrial's under all circumstances but it doesn't reach tingly in the hands or up the forearms until doing work. I don't mind taking it back to Home Depot and saying its defective, but if the second one is as bad I'm not sure they'd be as agreeable a second time....

As an example, with a grinding disc the Makita chatters/hops a bit, the industrial just grinds. I feel like I can use the industrial for 8 hours a day and not really notice but after a few minutes of the Makita I'm thinking is this going to give me carpal tunnel or nerve damage.

 

[Jim Pelosi]

Check and make sure the flat shaft nut by the gear head is perpendicular to the shaft. Might just be a defective nut making the wheel oscillate.

Sent from my SM-G360P using Tapatalk

 

[General Geoff]

Only when doing work.

Too much play in the bearings, methinks.

I recently picked up a Makita SJSII 4.5" angle grinder (model #GA4542C) and she's smooth as glass even under heavy load. I used it for a half hour yesterday cutting a very large, heavy, industrial filing cabinet in half, no numbness or discomfort. So not all Makita electric grinders vibrate badly.