Grizzly G0766 vibration issue. If you have this lathe, please comment

[Thomas Wilson80]

Also curious if the OP ever resolved the issue.

[Clint Bach]

I had a noise with my g0766. It all went away after I removed the knock out bar from the spindle. Boy did I feel, well... Sometimes it's the stupidly simple things that bite me the hardest...

YMMV....

Clint

[Brice Rogers]

I had vibration on my G0766 and it was a knocking sound. It turned out that I didn't have the headstock locked down. Stupid on my part.

[Clint Bach]

Just a thought... Removing the headstock from the bed would be too much of a job for me. That thing is more weight than I can handle by myself. But, you could loosen the head and put some rubber or foam pads between the head and the lathe bed temporarily. If it still knocks you know it's the head. This might tell you where to look for the noise. Have you checked if that washer behind the spindle pulley is tight? I wonder what that washer actually is supposed to do...

Clint

[Harold Rosee]

PART 1.

I also had this exact same problem sine I bout my G0766 new back in May. It started a noticeable vibration around 1050 rpm up to around 1140 rpm where it went away. I have just been turning around that speed and ignoring it. I have never called Grizzly. Just didn't want to mess with it until a few days ago. I searched and found this post and I am glad I did. I had really never done a good job at leveling my machine. So I went out in the garage and got out the level. I got everything level and sure enough all but a little bit of the vibration was gone. But I wanted it perfect so I looked some more. I did notice that the spacer between the pulley and the bearing appeared to be out of round. While running the lathe real slow I noticed that the belt had a bad spot in it that made a slight jerk each revolution even though the pulley was running true.

[Harold Rosee]

Part2.

So I remove the parts including the pulley so I could get at the spacer. What is interesting about the spacer is the hole in it is larger that the shaft by a good 1/8 inch. Did they put the wrong spacer on my lathe? It does have a little raised race on the side that touches the bearing but there is no way to keep it centered. I scratch my head and put it back together. The part is just $7.25 so I ordered another one just to see if it's the same. Has anyone else had there's off?? Are you seeing the same thing?

At the same time I ordered a new belt but NOT from Grizzly. I ordered a Gates 220J6 belt off Amazon. I put it on today and happy to report that all vibration id gone. It is smooth as can be even with my chuck on. So in the end the proper leveling got rid of 97 percent. The belt got rid of the other 3 percent.

The only thing that bugs me is that spacer. While it's not causing me a vibration problem it is all over the place and doesn't look right.

I know this is not the Grizzly forum but it's where the OP posted so I added mine here.

Harold

[Roger Chandler]

Part2.

So I remove the parts including the pulley so I could get at the spacer. What is interesting about the spacer is the hole in it is larger that the shaft by a good 1/8 inch. Did they put the wrong spacer on my lathe? It does have a little raised race on the side that touches the bearing but there is no way to keep it centered. I scratch my head and put it back together. The part is just $7.25 so I ordered another one just to see if it's the same. Has anyone else had there's off?? Are you seeing the same thing?

At the same time I ordered a new belt but NOT from Grizzly. I ordered a Gates 220J6 belt off Amazon. I put it on today and happy to report that all vibration id gone. It is smooth as can be even with my chuck on. So in the end the proper leveling got rid of 97 percent. The belt got rid of the other 3 percent.

The only thing that bugs me is that spacer. While it's not causing me a vibration problem it is all over the place and doesn't look right.

I know this is not the Grizzly forum but it's where the OP posted so I added mine here.

Harold

Harold, I put a note for you on the GGMG. There is a recess in the side of the pulley, and that raised area on the side of the spacer fits into the side of the recess on the pulley...sort of like a mortise and tennon. Check to see if that spacer is seated all the way into the recess and tighten down the pulley with the set screws onto the spindle, as that is what holds everything in place. It could have vibrated lose, and could be a very easy fix.

[Patrick Morris IV]

A friend of mine has the 766 and had the same problem. We corrected his problem, after checking for bed level, by putting a blank on the lathe so that it would be out of balance and spinning it up to the start of vibration (also between 900-1100 rpm) then checking each of the feet for movement. If a foot seemed to be moving even slightly, tightening it towards the floor solved his problem.

Oops, didn't see that this post started in 2018 ;-)