What's new
What's new

Bad noise from spindle motor

poxino

Aluminum
Joined
Jan 11, 2017
hello guys,

I had a look at similar threads within this forum, but I think my case is slightly different, hence I am posting a new thread.

The machine is a EUROTECH ELITE, control is FANUC 18T,yom 1997

So, I was running a job on my CNC lathe, then after about 300 parts, I heard a knocking noise, then looked on the screen, and there was an alarm saying spindle alarm 751.

I couldn't check what alarm was showing on the drives on the back, as there is a safety device that as soon as you open the electrical cabinet door, the power is cut off.

If I try to spin the spindle with my hand, I can see some rpm coming on the screen, either if I command S100 m3, all is ok, but if I command something like S1000 m3, there is a bad noise coming from the spindle motor, and actual spindle speed does not go above 150 rpm.

I checked all the cables on the back and they all seem in good condition and plugged in properly, the cable which plugs in on the actual spindle encoder looks like it has some oxidation on the connector itself, I tried to unplug the connector, but I am not totally sure how you would do it?
Maybe it would benefit from a good clean.

the belt tension between the spindle and spindle encoder pulley seems good too.

I am not really sure what is calling the problem, any help is highly appreciated.

Another thing, I just checked, if I try to command for instance m3 s500, I can see the spindle load going up 180%, in a combo with that bad squeaking noise.

I am machining the 1st order for a new customer, and there we go , the machine breaks down :cryin:
 
hello guys,

I had a look at similar threads within this forum, but I think my case is slightly different, hence I am posting a new thread.

The machine is a EUROTECH ELITE, control is FANUC 18T,yom 1997

So, I was running a job on my CNC lathe, then after about 300 parts, I heard a knocking noise, then looked on the screen, and there was an alarm saying spindle alarm 751.

I couldn't check what alarm was showing on the drives on the back, as there is a safety device that as soon as you open the electrical cabinet door, the power is cut off.

If I try to spin the spindle with my hand, I can see some rpm coming on the screen, either if I command S100 m3, all is ok, but if I command something like S1000 m3, there is a bad noise coming from the spindle motor, and actual spindle speed does not go above 150 rpm.

I checked all the cables on the back and they all seem in good condition and plugged in properly, the cable which plugs in on the actual spindle encoder looks like it has some oxidation on the connector itself, I tried to unplug the connector, but I am not totally sure how you would do it?
Maybe it would benefit from a good clean.

the belt tension between the spindle and spindle encoder pulley seems good too.

I am not really sure what is calling the problem, any help is highly appreciated.

Another thing, I just checked, if I try to command for instance m3 s500, I can see the spindle load going up 180%, in a combo with that bad squeaking noise.

I am machining the 1st order for a new customer, and there we go , the machine breaks down :cryin:

Sounds like your spindle bearings or motor bearings are toast
 
hello guys,

I had a look at similar threads within this forum, but I think my case is slightly different, hence I am posting a new thread.

The machine is a EUROTECH ELITE, control is FANUC 18T,yom 1997

So, I was running a job on my CNC lathe, then after about 300 parts, I heard a knocking noise, then looked on the screen, and there was an alarm saying spindle alarm 751.

I couldn't check what alarm was showing on the drives on the back, as there is a safety device that as soon as you open the electrical cabinet door, the power is cut off.

If I try to spin the spindle with my hand, I can see some rpm coming on the screen, either if I command S100 m3, all is ok, but if I command something like S1000 m3, there is a bad noise coming from the spindle motor, and actual spindle speed does not go above 150 rpm.

I checked all the cables on the back and they all seem in good condition and plugged in properly, the cable which plugs in on the actual spindle encoder looks like it has some oxidation on the connector itself, I tried to unplug the connector, but I am not totally sure how you would do it?
Maybe it would benefit from a good clean.

the belt tension between the spindle and spindle encoder pulley seems good too.

I am not really sure what is calling the problem, any help is highly appreciated.

Another thing, I just checked, if I try to command for instance m3 s500, I can see the spindle load going up 180%, in a combo with that bad squeaking noise.

I am machining the 1st order for a new customer, and there we go , the machine breaks down :cryin:

Systematical troubleshooting :) Isolate things to the smallest possible subsystem. In your case take off the belt, spin the spindle by hand to see if you have any noise or grinding. run the motor with the belt off, listen to noises, and check the load. Hope it is the motor bearings. Good luck :)

dee
;-D
 
Systematical troubleshooting :) Isolate things to the smallest possible subsystem. In your case take off the belt, spin the spindle by hand to see if you have any noise or grinding. run the motor with the belt off, listen to noises, and check the load. Hope it is the motor bearings. Good luck :)

dee
;-D

Hello guys, just an update, as the spindle amplifier alarm suggests replacing the spindle drive, I had it repaired, today, I put it back, and still the same noise from the spindle motor, it definitely seems like is the spindle motor to me , any other suggestions?
 
Hello guys, just an update, as the spindle amplifier alarm suggests replacing the spindle drive, I had it repaired, today, I put it back, and still the same noise from the spindle motor, it definitely seems like is the spindle motor to me , any other suggestions?

hello there,

I just looked at this again , although I am not a service engineer , and I don't know much about CNC machines , I think the problem is related to the motor and not the spindle drive.

When above 150 rpm , that squeaking noise comes with a vibration on the belt , so would this be something related with belt , pulley or spindle motor bearings , what do you suggest me to do?

Thanks in advance
 
The first thing is to take the belt off, see if you still have the noise, try spinning the spindle and the motor by hand and see if you can feel anything bad.

or get a tech in to look at it.
 
hello there,

I just looked at this again , although I am not a service engineer , and I don't know much about CNC machines , I think the problem is related to the motor and not the spindle drive.

When above 150 rpm , that squeaking noise comes with a vibration on the belt , so would this be something related with belt , pulley or spindle motor bearings , what do you suggest me to do?

Thanks in advance

There is no magic inside the spindle motor. It is like any other 3 phase induction motor.With a sensor on it.

The drive should have a led display on it. what does it say when it is alarmed? 8. maybe?
 
there is no such thing as a silly question, but, and with no disrespect ment, if you're not sure of how to take a drive belt off are you going to be safe to work on a machine that can kill you in about 300 ways?

never even seen one of those machines, but ill take a wild stab in the dark.

In most machines there will be a rocking mount that the motor is bolted to, it should have a single screw somewhere to adjust the tension, slacken it up then pop the belt(s) of the end of the motor shaft. it can be hard to get the belt(s) off the spindle (it might well be between the bearings and the chuck cylinder) if you cant take it right off cable tie it up out of the way so it cant catch on anything.
 
You said you had the drive repaired, by whom? Did they run it on a test stand?

AL29 is not a spindle amp related alarm, as you said it had earlier.

The sensor inside the motor back to the amp is analog, you mentioned that the connector is corroded.I would try to clean that up.
 
From what I remember was alarm 29

You have very short term mermory loss Cause you said in the 1st post this ;)

seriously though Get it checked out my a tech if you cant figure out how to disconnect the belt. like said about you can get hurt.

hello guys,

I had a look at similar threads within this forum, but I think my case is slightly different, hence I am posting a new thread.

The machine is a EUROTECH ELITE, control is FANUC 18T,yom 1997

So, I was running a job on my CNC lathe, then after about 300 parts, I heard a knocking noise, then looked on the screen, and there was an alarm saying spindle alarm 751.

I couldn't check what alarm was showing on the drives on the back, as there is a safety device that as soon as you open the electrical cabinet door, the power is cut off.

If I try to spin the spindle with my hand, I can see some rpm coming on the screen, either if I command S100 m3, all is ok, but if I command something like S1000 m3, there is a bad noise coming from the spindle motor, and actual spindle speed does not go above 150 rpm.

I checked all the cables on the back and they all seem in good condition and plugged in properly, the cable which plugs in on the actual spindle encoder looks like it has some oxidation on the connector itself, I tried to unplug the connector, but I am not totally sure how you would do it?
Maybe it would benefit from a good clean.

the belt tension between the spindle and spindle encoder pulley seems good too.

I am not really sure what is calling the problem, any help is highly appreciated.

Another thing, I just checked, if I try to command for instance m3 s500, I can see the spindle load going up 180%, in a combo with that bad squeaking noise.

I am machining the 1st order for a new customer, and there we go , the machine breaks down :cryin:
 
hello guys ,

I have an update on this , I had an engineer in , and he confirmed the fault is with the magnetic pulse coder assembly, particularly with the sensor on the motor.

I wasted 2500$ servicing spindle drive that was probably not needed , now for a new magnetic pulse coder assembly over $6000 , I wonder if I can get the part number only for the sensor itself rather than the whole lot if that can be an option , but I couldn't find any part number or the sensor itself.
 
hello guys ,

I wasted 2500$ servicing spindle drive that was probably not needed , now for a new magnetic pulse coder assembly over $6000 , I wonder if I can get the part number only for the sensor itself rather than the whole lot if that can be an option , but I couldn't find any part number or the sensor itself.

$6K for a pulse coder? Ouch!

Any chance a company like this might help (recently linked in another thread):

Oracle Encoder Service LLC the highest quality CNC manufacturing encoder feedback sales and service firm for Fanuc Yaskawa Mitsubishi...

Worth a call at least to see if the old unit could be repaired as a spare.
 
hello guys ,

I have an update on this , I had an engineer in , and he confirmed the fault is with the magnetic pulse coder assembly, particularly with the sensor on the motor.

I wasted 2500$ servicing spindle drive that was probably not needed , now for a new magnetic pulse coder assembly over $6000 , I wonder if I can get the part number only for the sensor itself rather than the whole lot if that can be an option , but I couldn't find any part number or the sensor itself.

What is the motor part number

What is the part number of this magnetic pulse coder you were looking for?
 








 
Back
Top