Question about Grizzly 0490x 8" jointer

Well known issue with those jointers. First check the pulley set screw to make sure it is tight. If that isn’t it there is a laundry list of things to try, hopefully that fixes it if not let me know and I will suggest some other “fixes”.

Forgot to mention when you check the set screw take it OUT first, sometimes there is a second set screw under the first one! If that is the case tightening the top one won’f do any good if the lower one is loose too.

I get the same thing, along with a colossal belt slap at startup. It really needs an idler/tensioner pulley.

-- My broker promised me he would treat my money as if it were his own. Trouble is, he did.

AHuxley, I checked the 2 set screws on the motor pulley and they are both tight. There is also only one screw per hole. There isn’t any play in either pulley. Thanks for the help though. Any other suggestions?

JJohnston, how long have you had the jointer for and has the belt shown any sign of wear from the slapping?

The belt slap is “normal” on this machine¹, but it can be fixed. At least in my case, i replaced it with a properly tensioned link belt and get no slap anymore. I’ve seen a number of solutions.

Someone on another forum also claimed griz tech support told them the shudder-on-stop was a harmless motor issue².
Mine doesn’t do it, so i can’t help you there.

[1] If you google search, you can see the belt slap on this machine has been complained about since late 2007.
[2] http://www.woodworkingtalk.com/f12/new-jointer-vibration-g-0490-griz-14493/, search on the page for “returning to zero”

Does the motor have a centrifugal switch? They make a very noticeable clunk when the motor is shut off and slowing down. If that is it, there is nothing to worry about and it’s completely normal.

Cheers,
Brad

PS: Try doing a google search for “Grizzly G0490 centrifugal switch“

-- Brad in FL - To be old and wise, you must first be young and stupid

I’ve had mine a couple of years, but I haven’t been back into the cabinet since I got it set up. Now might be a good time to check up on it. Are we talking about the older V belt rather than the newer ribbed? That’s what mine has.

-- My broker promised me he would treat my money as if it were his own. Trouble is, he did.

DannyB: Thanks for the link. I might go ahead and try changing the belt. I find it very irritating that it does that though. Do I have to change the pulleys to match the V style belt or is it a direct replacement?

MrUnix: The slapping comes probably between 5-10 seconds after the motor is cut off so I’m not sure it is related to a centrifugal switch (based on the link you posted). I don’t notice any surging sound from the motor or any prolonged running of it either after I hit the off switch. I do think that it is a possibility that motor breaking is playing a role in the sudden belt slapping at a certain rpm after motor cut off. I am going to research that route also.

JJohnston: it is a ribbed style belt.
Thank you guys for the help. This thread has been more helpful than customer service so far. When I talked to the technical support guy at Grizzly, he acted like it was an unusual problem and it could only be based on how the pulleys/belt was aligned. I had read about this issue before my purchase but it was from an older thread and I assumed that technical support would have had a fix for the issue. As of now, I’m leaning toward DannyB’s posted link:
“I got a call from the Grizzly tech department yesterday. They said that some(got that? some?) of the motors on the G 0490 have an electro-mechanical problem that causes the motor to generate electric after it is powered down and the rpm’s are returning to zero, causing the offending shudder(vibration). They said that although they didn’t think this would harm anything(I think it will) that they would be willing to send me a new motor.I got a call from the Grizzly tech department yesterday. They said that some(got that? some?) of the motors on the G 0490 have an electro-mechanical problem that causes the motor to generate electric after it is powered down and the rpm’s are returning to zero, causing the offending shudder(vibration). They said that although they didn’t think this would harm anything(I think it will) that they would be willing to send me a new motor.”

This might also be the same thing that MrUnix is talking about. If so, I would like to know what makes it happen in some motors and not others. Also, is there any potential long term damage to the motor from this abrupt breaking? Thanks again guys. It’s awesome that other people are so willing to help out!

Mike

I doubt you have a braking system in that motor! However, the centrifugal switch sometimes gets mistaken for one because that is exactly the kind of sound it makes. Hard to explain with words, but the switch will snap back into it’s closed position sometime after you turn the machine off.. the motor needs to drop below a certain RPM for the springs to overcome the centrifugal force. 5-10 seconds sounds like that is what it is. I have seen it where they make very little or no noise when brand new and then start to become more pronounced after some use and increased clearances from wear. But heck, if they are willing to send you a new motor, I’d go for it!

Cheers,
Brad

-- Brad in FL - To be old and wise, you must first be young and stupid

MrUnix: I guess that’s what’s going on then. I can live with the noise but do you know if there is any potential damage to the motor or belt because of the way the centrifugal switch is effecting the motor? I’m going to try to call grizzly this week. If they have any other ideas i’ll be sure to let you guys know. Thanks again for helping with the diagnosis. It’s much appreciated.

The belt was a direct replacement on my version of the g0490. I have one of the non-cogged v-belt versions (IE before they moved to “serpentine belts”).

I replaced the belt with a “Grizzly H9815 Power Twist® V-Belt, 1/2” x 4”.

While i had the belt off, I also made sure the pulleys were properly aligned.

You say you have one of the ribbed v-belts, so i don’t think this will work in your case.

Out of morbid curiosity, try taking the belt guard off (part 204 on http://www.grizzly.com/products/g0490/parts) and watch the belt as it spins up and down.

IIRC, the sudden tension on mine was causing the belt to band into the side of the belt guard on startup, causing the slapping noise. However, this was 3+ years ago, I could be misremembering.

In any case, with the belt guard off, you should be able to see if anything bad is happening, and be able to quickly determine how to fix it.

Mine is a month or so old and has done this since the first time I used it. I contacted tech support and they said not to worry about it so I haven’t. I figure if I have problems down the road I have their email telling me not to worry about it saved so could always show that to them and say if they’d dealt with it when I complained then whatever problem might have been avoided and hope they make it right.

I would be curious to know if you find a solution.

First do you have a cogged belt or a Poly-V belt if it is the former a link belt is a direct fit, if the latter it is not. Be aware that SOME of these machines (ah the tight Chinese tolerances) have a section where the belt goes into the cabinet where the raw metal edge is very close to the belt and can wear a link belt due to its extra thickness.

As mentioned try watching the belt on spin-down and see if it is bouncing around.

You may also want to check the pulley aligment, it has known to be an issue too.

This jointer has always been plauged with these noise issues and it seems to be a different set of fixes that work on any given machine but its price seems to outweigh the issue when compared to the prices of the PM and Delta that don’t have any noise issues.