Mini mill table binding

Manufacturing tolerances on these machines are wide enough that one person's fix may not apply to another machine. Case in point, the feed screw nut's set screws on my machine are firmly tightened down and it doesn't bind up.

If the nut can get cocked sideways that would appear to be a recipe for binding up. Although it's a bit of a pain to pull the table off, it might be worthwhile to do that and inspect the slot where the X axis nut is installed (inspect the nut, too). You might find a paint chip or other residue, or a manufacturing defect that keeps the nut from sitting flat in the slot. It's been long enough that I don't recall if the mating surface is machined or is a "raw" casting surface on mine. Hopefully it is machined but ya never know....

On my machine, I can remove the table top without having to move it all the way to the end. IIRC, I loosen the gib screws and slide the gib out, then remove the end cap mounting bolts (this latter step separates the feed screw from the table top). Then rotate the front or back of the table up to clear the dovetail. This will probably work for you, too.

If you do perform the inspection, that would be a good time to make sure the feed screw is properly greased.

BTW the Y axis mod to add a thrust bearing is worth it. But, since you've got a mill, it's relatively straightforward to make your own-- see here. This is not my design but it works well for me. One advantage of the DIY approach is that it has two thrust bearings so the Y axis then has the same configuration as the X axis. The commercial thrust bearing mod only has one thrust bearing so it still is possible to over-tighten the handwheel nut.
 
I had a similar problem on my lathe cross feed. After coating the ways with marking fluid iI couldn't find anything wrong. I put a DI on the leadscrew and it was bent. The screw would flex in the middle of travel to allow clearance for the bend but near the end of the travel the bearing wouldn't allow enough flex for clearance so it would bind. I took the leadscrew out and straightened it and the entire travel was smooth again.
 
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