Carve shifting right to left

I’m confused how to troubleshoot this one. On small carves or routing small designs across large areas everything tracks fine. However if I carve a larger design, let’s say a 24" square (to make it simple), it will be 24" along the y-axis but gradually the dimension along the x-axis narrows. The X-carve shifts about 1/16" when it gets to the right side, then the left side shifts the same amount. I’ve included pics below. Does this even make sense? Any help would be very much appreciated!

example 1
example 2
example 3

You might need to tighten your belts or adjust (increase) the current to the stepper motors. You might be loosing steps.

You were correct, I tightened my belts (way more than I thought was required) and that resolved the issue. Thanks. I’m really quite amazed at how tight they are now! :open_mouth: