I'm having trouble with the grub screws on the belts loosening during prints. I tighten them before a print but tend to find that during the print the screws have loosened again enough to cause layer shifting. This seems to be mostly a problem in the Y axis.
I'm printing at 30mm/s which seems quite a slow speed to me. Has anyone had any experience of this or aware of any fixes? Any help would be greatly appreciated.