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Review the involute interpolation block (G02.2 or G03.2) and verify all required parameters are present: base circle center (I, J for XY plane), involute radius (R), and start/end angles or arc definition.

Check that the I, J, K values correctly define the base circle center position from the programmed start point, not as absolute coordinates unless specified by parameter setting.

Verify the R value (involute radius) is positive and geometrically valid for the intended involute curve. Ensure the radius is larger than the base circle radius.

Confirm the angle specifications or endpoint coordinates create a valid involute geometry. Check for typos in decimal points or sign errors.

Check if cutter compensation (G41/G42) is active or commanded in the same block as the involute interpolation. Cancel cutter comp with G40 before the involute block.

Ensure G40 is commanded at least one block before G02.2/G03.2 to fully cancel compensation mode.

Verify that only the two axes of the selected plane (G17/G18/G19) are commanded in the involute block. Remove any third-axis movement or use separate blocks.

Check for feedrate override commands, M-codes, or tool change commands within the involute interpolation block. Move these to separate blocks before or after the involute command.

Ensure no scaling (G51), rotation (G68), or mirror image (G50.1/G51.1) functions are active during involute interpolation, as these may not be supported depending on control series and parameters.

Verify that a valid plane selection (G17 for XY, G18 for ZX, or G19 for YZ) is active before the involute interpolation command. Add the appropriate G-code if missing.

Check parameter 5520 (or series-specific equivalent) to confirm that involute interpolation is enabled in the control. Bit settings must allow G02.2/G03.2 functionality.

Parameter changes require proper authorization and should be documented. Incorrect parameter settings can affect other machine functions.

Review the control specification and option list to verify that involute interpolation is included in the machine's purchased software options. Check for option bit in parameter 14800 series if applicable.

If recent parameter changes or memory clear occurred, verify all involute-related parameters are correctly restored from backup or OEM specifications.