Width of toolpath deviates from tool and differs depending on path-direction

Hi, just received a new Snapmaker Original.

I tested cnc on 3 mm plywood and 3mm bamboo.
Making a square carve depth 2mm and a circle, cutting through the material.

Problem (see image):
The tool is a flat mill 3,175 mm. In 1 direction the width of the carving is 3,5 mm (not 3,175) and in the perpendicular direction it is 4,5 mm.
The cut circles are not real circles but ellipses.

I do not mind so much that the width differs (a little) from the tool dimension (though 1 mm is much), but that it differs depending on the toolpath direction is a problem.

Do you recognize this problem? How could it be solved?


I guess you have to carve slower and or with more passes.
It seems your machine is bending a bit.
How many passes did you carve the 2mm depth?