PDA

View Full Version : Bearing Noise in my PLS 3.60



David Dustin
04-08-2010, 9:27 AM
When we run our PLS at high speed we can hear a light chatter.
There is also a pattern created on certain anodized aluminum that is there regardless of the speed we run the head.

We have replaced the head bearings once already.
Does anyone have an idea as to how expensive a new alluminum cross rail is?

We did not opt for the annual support from our supplier as we dont have the volume to justify it, and I think I need to give them credit card just to call.......

Thanks in advance if you have any ideas.

David

Richard Rumancik
04-08-2010, 10:46 AM
By head bearing, you mean the bearings on the carriage assembly? It could be the bearings in the x-motor. They take a lot of abuse becasue they are constantly changing direction, and never get up to proper speed to make the bearings work properly. You need to isolate them from the carriage bearings to be able to test them. This could mean removing the motor itself. Or is there some way to easily disengage the belt that drives the carriage? If so, you may be able to spin the motor by hand without removing it from the mounting. I would unplug the motor with the machine off before trying this.

I don't know if you have steppers or servos on this machine. If it is steppers, you may feel some cogging due to the magnetic detents which makes it harder to tell if the bearings are bad. There are usually 200 positions per revolution where you will feel a detent. If it is a servo it should spin smoothly.

Do you have any reason to think there is something wrong with the crossrail? I would not expect it to be a problem unless it was badly pitted or scored.

Mike Mackenzie
04-08-2010, 11:59 AM
David,

24" Rail p/n 700035700D $200.00 you can order it from here support@ulsinc.com

David Dustin
04-08-2010, 12:06 PM
Do you have any reason to think there is something wrong with the crossrail? I would not expect it to be a problem unless it was badly pitted or scored.

Richard,
I have disconnected the Head from the belt and the noise is present.
The bearings were replaced not too long ago.
There isnt any visible pitting or scoring on the rail that I can see.

The traverse motor is a Stepper (micro -stepper) and there isnt any pronounced "cogging" as could be present if it was a 1.8 degree stepper.

Thanks,
David

David Dustin
04-08-2010, 12:09 PM
Mike,
Thanks for the part number.

Do you happen to have the part number for the bearings?
I thought I seen where there were some over sized bearings that we a recommended retrofit (but it may have been for the VLS)..

Thanks,
David

Scott Shepherd
04-08-2010, 1:26 PM
Mike,
Thanks for the part number.

Do you happen to have the part number for the bearings?
I thought I seen where there were some over sized bearings that we a recommended retrofit (but it may have been for the VLS)..

Thanks,
David

143-0001-9 is the Flat Bearing kit.

Eric Seest
04-08-2010, 9:20 PM
David,
Make sure that the pulley on the motor is not rubbing. I had to replace the stepper motor and noticed that the pulley was rubbing the motor. Also check the belt tension, don't remember off top of my head what it is supposed to be.

Scott Shepherd
04-09-2010, 9:55 AM
David,
Make sure that the pulley on the motor is not rubbing. I had to replace the stepper motor and noticed that the pulley was rubbing the motor. Also check the belt tension, don't remember off top of my head what it is supposed to be.

Now that you mention it, mine too. When they replaced the pulleys and belts and bearings, they did notice the belt was rubbing on one side of the flange on the little drive pulleys.

Mike Mackenzie
04-09-2010, 11:33 AM
Scott, David

The P/N I have for the X axis Bearings Flats is 143-0001-08A. I believe your P/N includes the axles.