14920

Common Causes

• Intermediate point (I, J, K parameters) collinear with start and end points, making circle definition geometrically impossible
• Intermediate point lies outside the line segment between start and end points rather than between them
• Incorrect calculation or input of interpolation parameters I, J, K values in the CIP block
• Machine coordinate system misalignment or calibration error causing point calculation discrepancies
• CAM post-processor error generating invalid intermediate point coordinates

Troubleshooting Steps

1. 1Verify the part program block syntax: confirm I, J, K parameters define a point that lies geometrically between the start point and end point, not on the extended line
2. 2Calculate or recalculate the intermediate point manually using the part geometry; ensure the three points form a valid triangle, not a collinear arrangement
3. 3Review the CAM post-processor output for the affected block and regenerate the NC code if using automated programming
4. 4Check machine zero offset and coordinate system calibration; perform a test block with known good CIP coordinates to isolate software vs. calibration issues
5. 5Edit the program to reposition the intermediate point off the line connecting start and end points, or convert to standard circle interpolation (G02/G03 with radius or arc center offset)