Nikon Eclipse E100

[jlknight]

I am a lab tech for the biology department at a college. I've been tasked with getting the mechanical stage to move easier. The Y-movement (back and forth) is smooth and easy, the X-movement (left/right) is difficult to turn.
Tutorial videos I've found show to separate the stacked knobs and there should be a tension ring between them. That is not the case with this set. There is a small nut on the bottom that I've loosened, the dial will then turn easily however then there is no stage movement when the knob is turned. When re-tightened, even at minimal amounts, the stage goes back to being highly difficult to turn. Is there a particular area that I need to grease? a particular way that everything needs to be situated in order to get the stage to move smoothly again?
Thank you

[apochronaut]

Questions like yours are hard to answer unless someone has had that particular mechanism apart, because despite the similarity of function between dropdown coaxial stage controls, there are various ways to design them. i know of one design for instsnce that pressfits a gear to the end of a shaft on a taper, rather than a spline or square shank.
If I had to guess based on the description of the problem I would suggest that the pinion gear is binding on the track gear. .I presume it worked o..k. at one time and they usually get looser due to wear over time unlesd the lubricant dries out. The E100 is a little too new for that to have hsppened, I would think.
It almost sounds like something has gotten jammed in the gears. Even s good sized thread or tissue would fo it.