On my PM30, I made a test piece today, first cut in metal, and before doing so, I tried to adjust all 3 of my gibs.

I noticed that on my Y axis, I can push the taper as far as the screws will allow, and it still is not overly tight. By hand,

My X and Z both are able to be completely locked down by tightening the gib strip, and I needed to back off the gib quite a bit to be able to run at a reasonable rapid speed for both X and Z.

I don't have any slop that I can feel in any Y axis, but in my test piece, I noticed a lot of chatter in the Y direction, which I am somewhat attributing to the gib not being tight enough.

To be fair, my stand is not very sturdy at all (stand that came with mill), and the only 2 screws from the base actually line up between the mill base, and the stand, so it is probably not overly tight there either. So, between the lack of overall rigidity in the machine, the stand being flimsy, and the mill not being attached great to the stand, there is probably plenty of variability contributing to the chatter. All of those other things can be worked out short of rigidity.

The reason I am leaning towards the Y gib, my X axis has a bit of chatter, but not nearly as bad as the Y, which is quite bad. I ran the same speeds, and the X should be subject to the same variables as Y, so I am deducing the Y gib.

My main question is, is there anything I can do with my Y gib strip? Can I shim it somehow, and if so, how?

I assume a new one could be made, but I don't really know the dimensions, nor the process for making a new one, so that would be last resort.

I know that QMT does not even offer the PM30 anymore, so not sure I could even buy a new one from them.

So if anyone has any thoughts or suggestions, I would appreciate hearing them.