@Adam_J I assume you are running a stock machine with stock control software?
If so we cannot look at what is being sent the machine.
Either the source being sent to the machine has an error in it or you have found something endemic to all K40’s, which would be weird and unlikely.
I noticed in the last picture, if I have them lined up right, there seems to be an offset at the start. This observation could be erroneous due to the pictures perspective.
- Is A&B the starting points of the circle ?
D: seems to be slightly offset, overlapped etc.
C: seems to have a chamfer on the edge for some but not all the circumference.
Could the software be at fault by not starting or ending a circle properly??
Suggestion: Create arcs, circles and lines of different types to see if all objects do this.
Community Call Out: You could also ask others in this community to cut similar circles to see if all our machine do this. Mine is broke! Post the specifications of the circle you are cutting.
Suggestion You could also try K40 Whisperer (free software) and see if it does the same thing with a similar circle.