Originally Posted by
awerby
Do you notice any vibration at the tool tip, as the cut progresses? Or is the spindle rock-solid, not deflecting even if you lean on it hard? Cutting wood puts a lot of strain on the machine, which can dig in and release as the grain permits, if the whole assembly isn't rigid enough to discourage that. To me, the marks you circled have the look of harmonic vibration rather than lost steps. If there's anything you can tighten to get more rigidity in your setup, do that.