G0695 Mill Vibration Issues! I Need Guidance....

[tmarks11]

Well looks like you might have found the culprit. Now see if Grizzly will send you a new one.

Ohh... and go buy a new dial indicator. Even a $15 one. You NEED one to tram your mill.

Post a picture of your motor. Most motors like this have a TEFC (Totally Enclosed Fan Cooled) motor... where the fan is under a cowling on the back which blows are over the outside of the motor. Unusual to find a motor that is a Totally Enclosed Non-Ventilated (TENV) motor on a mill, which is what it seems you have, since I suspect it would overheat during extended milling, especially when running with a VFD.

EDIT: looking at your picture in the first post, that looks like a TEFC to me. That black cowl on the top of the motor should cover the fan, and should be attached to the motor by three little screws.

 

[Ironken]

Your motor must be different because mine definitely has a plastic fan.

You aren't going to get to far in this hobby without a dial indicator.

It may be different Doogie. To expand on the indicator situation. The mill is my first piece of equipment on the machining side of my toybox. I go in phases.....by that I buy the big hunks first, then the small stuff as money allows. That's how I outfitted my weld shop. The indicator will come along with tooling. But, I have a taste for top notch equip (the Grizzly being the exception.....a Bridgeport it aint) so until I stash enough to pop for Starrett, I'll hold off. I didn't wanna come off like a hack.

 

[Ironken]

Well looks like you might have found the culprit. Now see if Grizzly will send you a new one.

Ohh... and go buy a new dial indicator. Even a $15 one. You NEED one to tram your mill.

Post a picture of your motor. Most motors like this have a TEFC (Totally Enclosed Fan Cooled) motor... where the fan is under a cowling on the back which blows are over the outside of the motor. Unusual to find a motor that is a Totally Enclosed Non-Ventilated (TENV) motor on a mill, which is what it seems you have, since I suspect it would overheat during extended milling, especially when running with a VFD.

EDIT: looking at your picture in the first post, that looks like a TEFC to me. That black cowl on the top of the motor should cover the fan, and should be attached to the motor by three little screws.

Tmarks, I was surprised to find no fan (pic above). I literally just got a call from Grizzly. They want TIR of the shaft......so you guys win. Off to Horrible Freight I go for a cheapo DI. Thanks for helping a guy out. That applies to all of you!

EDIT: I'm a moron! My wife IS right!
I was looking at the parts diagram and there is a fan listed....what the hell?

 

[DoogieB]

Yeah, I took a picture of the motor on my mill:



The motors look very similar except for the mount. I was thinking there has to be a fan, so I grabbed the manual for your mill and looked in the exploded diagram and there it was, listed as part 203-2. You must have one of those motors that gives Grizzly a bad reputation.

Even with the extra fins, without active cooling those motor windings probably got pretty hot during break-in and it's not your fault. Grizzly should be sending you a new motor, TIR reading or not. They obviously screwed-up here.

 

[Ironken]

I agree! I have been pretty understanding to this point but, I am just about burned out on machine diagnosis. No complaints about Grizzly yet but, damn! Lets get some parts coming. The runout at the very end of the fan end of the shaft indicated .005" runout. Is that enough to cause my problems? I don't know. I am awaiting a call back from the tech.

 

[tmarks11]

Yep, that looks like a TEFC to me... except with no fan. Make sure you tell Grizzly about that, because if you end up spending an hour milling, say goodbye to the motor.

Guess I should have done what I normally do and check out the Grizzly drawings online (looks like you are missing PN203-2):


I don't know... your vibration looks worse than what 0.005" TIR would give you. See what Grizzly says. I would suspect that this is a rotor balancing issue (still means they owe you a new motor).

 

[Ironken]

I need to pass that info on to Grizzly but, I have a feeling they are going to blame the issue on the lack of a fan. As bad as the vibes are, I wouldn't be surprised if the spindle pulley (looks to have balancing holes drilled in it) has issues. Thanks for delving into this with me!

 

[mksj]

If you check the manual, the motor is specified as TEFC on the spec page and on the parts diagram. This is actually a bit unusual, because VFD systems often do not use a TEFC motor because of cooling issues below about 25% of base speed. TENV are designed for passive cooling, often there is a separate fan that cools the motor independent of the VFD speed. Shaft TIR of 0.005 for a Chinese motor is not unexpected, but it could also easily be a motor balance issue, sounds like sheet metal rattling. That it is missing the fan, really makes one wonder who is building these. You can also see the belt fluttering quite a bit, which could also exacerbate things. I would put on a higher quality cogged belt once you get the motor issue squared away.

 

[stupoty]

If it got properly hot during brake in it might have cooked the bearing grease/oil and made them run less than smothly. You could press your ear to the motor and turn the shaft by hand listening for any grinding type noises. (Don't have it plugged in when doing that)

Stuart

 

[John Hasler]

Yeah, I took a picture of the motor on my mill:

View attachment 126519

The motors look very similar except for the mount. I was thinking there has to be a fan, so I grabbed the manual for your mill and looked in the exploded diagram and there it was, listed as part 203-2. You must have one of those motors that gives Grizzly a bad reputation.

Even with the extra fins, without active cooling those motor windings probably got pretty hot during break-in and it's not your fault. Grizzly should be sending you a new motor, TIR reading or not. They obviously screwed-up here.

Looks like TENV. Does it say that on the nameplate? TENV stands for Totally Enclosed Non-Ventilated. Such motors are intended to operate with no fan.