Machine wont cut circles properly

I just got this thing. I cannot cut a circle for the life of me. They always turn out irregularly shaped. The smaller the circle the worse the discrepancy. I have ensured everything is tight and I have reduced my plunge / feed rate considerably. Nothing is working.

@joekorman What cad/cam software are you using? Can you post a .dxf file. Can you post a pic of a failed cut?

Check you anti-backlash nuts. One, or more, is probably too loose.

ah that was it. im ashamed to admit, I didn’t notice the rear backlash nut on the z axis behind the dust shroud. Got it sorted now though. Works better than I hoped. Thanks for the advice.

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You are welcome. One of the first things I tried to make with my Longmill was a circular box with a lid. Boy did that turn out bad till I figured out I needed to adjust my anti-backlash nuts.