Apollomrqz

i have drawn a semi detailed image in illustrator. when i go to cut it, the plotter overlaps parts of the image. an example is attached. picture a checker board with no fill just stroke. a few thousands of an inch gets overlapped over some of the squares. i drew it up in illustrator (vector) once done i expanded it and united everything(welded) then sent to my cutting software called stonecut. any and all help is much appreciated, thank you