So ive been doing some machining today and for some reason when i did a 15mm deep pocket at a 0.2 DOC at 400 Feed with spindle at max 2800 RPM.. the circle i wanted to pocket isnt a circle at all. its more ov an oval and it seems the top and bottom of the circle is off...

Think this may be caused by a inapropriate amount of backlash. im going to take the motors off tomorrow and see what if any couplers are on it

Stu