# Five Zeros



## Pescadora (Feb 14, 2020)

Like I said description of the vid, this is not a brag. In fact, it didn't even occur to me until my shop partner pointed it out. No voice audio because walking and chewing gum is hard enough. Running a cell phone vid, while repurposing this old plate for something else was kind of challenge. I quit after one lap before something bad happened.

But here's reason for the vid. Once the power feed was mounted (yesterday), what were somewhat stiff spots in the lead screw, now began to really howl. That noise is coming from the under table in the base, right side.  I.E., the split nut. One of the split nut screws has a stripped head so adjustment there isn't possible. After this part came off the table, I played with X gib a little with no effect. I then made a few copious shots of cutting oil onto the lead screw just to the right of the split nut and things got a LOT quieter.

Before the power feed was installed, you could feel 2 or 3 tight spots as the table moved right, but those were not evident going the other way.

I'm thinking lead screw issues. What's the opinion here?


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## brino (Feb 14, 2020)

Pescadora said:


> Before the power feed was installed, you could feel 2 or 3 tight spots as the table moved right, but those were not evident going the other way.



To me, that symptom sounds more like some problem in the ways.
-brino


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## RJSakowski (Feb 14, 2020)

From the cyclical nature, I would suspect that it is lead screw related.  Maybe a bent lead screw and dry lead screw nut or bearing.  Does the noise also occur when traversing from right to left?  If unidirectional, perhaps a thrust bearing.  I have seen less than perfect gears in aftermarket power feeds which could also cause a cyclical binding.


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## Pescadora (Feb 20, 2020)

No sounds when moving table left. Thrust bearing might be a good guess. A hint yesterday when creating a jig for a project. Definitely coming from the bracket behind the right hand wheel. We had that apart when the mill was brand new because of unacceptable resistance to turning the X-axis lead screw. Turned out the two thrust bearings were full of debris from the manufacturing process so we cleaned that out and put it back together.  The 51103 bearings are single direction thrust bearings which require specific installation, namely the washer with the tight shaft clearance mounted opposite from the housing on both sides. Reasonable to bet one bearing is installed backwards. When table is moving right, the lead screw is thrusting against the inner bearing. We may be hearing the tight washer installed in the bracket housing, sticking to the shaft and turning within the housing. Time to take the bracket off again and check.


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