"C" Model Machine Noise?

[Iron Mike]

I've noticed that there are some abnormal noises developing in the machine and would like to get ahead of the issues prior to a major failure.

One is a chatter at the start of a carving while the spindle is moving up and down at the left side of the rail checking board depth; it doesn't do it at any other time. A second noise that just started is hard to explain but sorta like a bad bearing (perhaps) and there has developed with this noise a very high frequency vibration that is quite noticeable when touching the cover over the motor vents. This last issue has developed in just the last two days of use. No problem with carving quality and everything seems to be tight and clean.

Where should one start to identify the source and correct. Machine has 132hrs on the cut motor and 156hrs of servo time; to date no parts have been replaced. Flex shaft running cool on a two hour carve. Seems to be quite early for needing motor brush or bearing replacement according to the maintenance schedule.

Appreciate any guidance.

[fwharris]

Mike,

Your chatter sounds is probably the Y/Z gear box bearings or a loose Y/Z motor mounting to the gear box.

On the vibration problem check the flex shaft sheath to make sure it is securely installed in the motor.

[Iron Mike]

Took everything apart in coordination with LHR and found one Z-truck roller bearing not rotating as freely as the other three. Warranty replacement on the way. We'll see how thing go upon return to operation.

thanks for the suggestion on the starting point.

Mike,

Your chatter sounds is probably the Y/Z gear box bearings or a loose Y/Z motor mounting to the gear box.

On the vibration problem check the flex shaft sheath to make sure it is securely installed in the motor.

[mtylerfl]

Took everything apart in coordination with LHR and found one Z-truck roller bearing not rotating as freely as the other three. Warranty replacement on the way. We'll see how thing go upon return to operation.

thanks for the suggestion on the starting point.

You can likely clean the bearing and get it rotating freely again. I've done that several times (maybe three or four times) over the last eight years and have never had to replace a bearing yet.

I lay down a bunch of old cloth towels inside the machine and squirt very generous amounts of WD-40 into the offending bearing (with the sweeper ring off, but the bearing still mounted). I then squirt pressurized air from my air compressor into the nooks of the bearing with a small orifice tip for streaming the air. I repeat this until the bearing moves freely and when I'm confident all the packed dust is pretty much gone.

So far, that has always worked for me. If you get yours going, you can save the replacement bearing for a spare. The Z bearing on my machine that seems to be prone to "gumming up" is the lower left one. Is that the case for you too?

[Iron Mike]

mtylerfl -

Yes, the lower left bearing was my problem as well!

I just finished cleaning up the bearing per your method and now have what seems to be a good spare. I temporally reinstalled it and remounted the Z-truck in the machine and no longer have any rough vertical movement. May just do all of them while awaiting the warranty replacement and perhaps prevent, or at least delay a future outage.

Such a big help . . . . . thanks.


QUOTE=mtylerfl;244068]You can likely clean the bearing and get it rotating freely again. I've done that several times (maybe three or four times) over the last eight years and have never had to replace a bearing yet.

[mtylerfl]

Glad that did the trick for you!