Random Vertical Gaps between External Perimeter

[christianlowed]

I've had the issue of many of my prints having a small gap between the external layers of the perimeter. Sometimes the gap appears on just one side of the object and not the other, or all-around in different heights. I've managed to mitigate the horizontal gaps between the infill and perimeters on top, but the Vertical gaps are still plaguing my prints. For Slicing, I use Repetitor Host and Slic3r.

[William]

Hi, See if the z-axis threaded rod is complete,
Check if the machine is loose.
If the bearing or pulley is stuck, add lubricating oil to lubricate.