Hi, I first want to say what a great help this site and forum has been to me in the last week. I used the info I've found here to return my machine to Z zero after it got lost. I am also getting close to figuring out my rs232 communications with what I have learned here.

Which brings me to my curent problem. "servo alarm -01 overload". And of course a "machine not ready" message. I was running the machine and it started sort of squeeking(very slightly) in the X-direction. It ran for about 20 - 30 minutes before freezing during a cut in the x- direction. I immedietly got the 2 alarms and havnt been able to do anything to get them to go away. I pulled off the covers and can move the ball screw, back and forth approx 1/10th of a turn before it seems to hit a stop. My first question is what did I break? and secondly, is there something I can do to move my Z out of the way while I fix the X drive problems? I almost forgot, the machine has a Fanuc controler. Thanks to who ever responds.

If its an older Fanuc control. There is a red reset button on the bottom of the axis drive slightly underneath the top board. Try pressing this reset and power down then up.

Thanks for the reply Petro! :) It is a older fanuc as far as Im concerned. Yellow end caps on the servo motors and the Fanuc controller is a 3M version I think. I will try this tonite and let you know what i find out. Thanks again!

Thanks Petro! :) I had to look around a little and it didnt appear to be tripped. I reset it anyway and turned off the machine and restarted it. Everything is working great now, except for the noise from the X-axis. With the covers off it is quite noisy. If I use the hand wheel and rock the X back and forth .010 there is a clunking/loud clicking noise. If I feed the X it clunks at first and then squeaks. The clunk noise seems to be coming from the black section of the servo motor. Any ideas?

There are generally only a few things that can cause axis clunking noise.
Loose ballscrew nut capturing the bearings on either end or bad bearings (most likely the cause).
Way covers sometimes clunk due to wiper friction
Ballscrew nut slop
No lubrication on ways

Thanks again Petro. I went ahead and pulled the servo motor tonite, but didnt get a chance to pull the bearing on the end of the ball screw. When I turn the ball screw by hand it is very smooth and no noise at all. I am wondering if I can hook the servo motor back up to its electrical conections. But not hook it up to the X axis and move the motor with the hand wheel so I could keep track of movement. So I could listen for noises from the motor. Would this work or would the motor lose its "home position"? Does the motor have a Home position?

It depends on what type of encoder the motor is using. If you have absolute encoders with no reference switches you will lose home. If you have incremental encoders the axis will feed to limit switches at the positive and negative ends of the stroke and base zero off of the distance between the two.

If you do have absolute encoders you should rezero the axis anyway since the motor or ballscrew either one could have moved once you removed the motor from the coupling.

Cody Stamper



(Note: The opinions expressed in this post are my own and are not necessarily those of machinetoolhelp.com and its management)

Thanks codyst. I have limit switches so I turned the machine on and its definitely a bad bearing in the servo motor. I pulled the motor out and cleaned it up. I removed the hub from the shaft end and pulled off the cap and encoder also. I marked each of their home positions but am not sure if it matters? Im going to be pulling the motor apart tomorrow night. Do either of you have any pointers for taking one of these apart? Are the bearings/seals something I can get from a bearing supply house? Is there anything else I should replace while I have it apart? Thanks very much for all your help.

I'm not sure about those motors. I've pulled a few red caps apart, but I've never even seen a yellow cap.

Cody Stamper



(Note: The opinions expressed in this post are my own and are not necessarily those of machinetoolhelp.com and its management)

I didn't even think about it being an older motor. If its a yellow cap then its a DC motor. It has brushes that can be removed and replaced. Often when they wear down it can sound like a bad bearing. The brushes are generally about 3/4 to 1" long when new for reference. Also the powder from the brushes and surface the brushes ride on can sometimes cause problems. But before pulling apart just change the brushes if they are worn.