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Circular interpolation milling has divots in axis quadrants or reversal using G02 and G03 commands

When machining a part using Circular interpolation machine problems can be found.  CNC programming for circular interpolation often uses G02, and G03 for example. Sometimes you can find in the holes that are circular interpolated the parts have slight divots in the quadrants for a particular axis as I found on a recent job. What I found in this scenario was that the ballscrew nut had lost  its preload and had excessive backlash. This type of backlash can not be taken out by a parameter to remove the dimple/divot. It may however help to position the axes in case you are drilling for point to point location for machining.

When machining parts using Circular interpolation machine problems often become exposed. It is a great way to look for problems in your machine without any high tech equipment. Sometimes placing an indicator on the circular interpolated hole and sweeping it can show backlash misadjustments, steps in the quadrants, divots, finish problems and more. CNC programming G02, G03 is often used in the task of circular interpolation. A smaller circle such as 1"-2" will illustrate the best  circular interpolated hole for CNC diagnosis.