278

Verify the tapping program line for correct format: G84 (or G74) Z__ R__ F__ (with spindle speed S__ active).

Calculate correct feedrate: F = Spindle Speed (S) × Thread Pitch. Example: S1000 with 1.5mm pitch requires F1500.

Check parameter 5200 (rigid tap mode) is set to 1 or appropriate value for your machine configuration.

Test with reduced spindle speed (50% of original) while maintaining correct F=S×pitch ratio to verify calculation.

Verify parameter 4513 (rigid tap synchronization error detection) setting - reduce value if oversensitive, typical range 100-500.

Document original parameter values before making changes.

Check parameter 4511 (spindle gear ratio numerator) and 4512 (denominator) match actual mechanical gear ratios.

Confirm spindle encoder is functioning - check parameters 3730-3732 for proper position coder settings and verify no position feedback alarms.

Perform spindle orientation test (M19) to verify position loop is closed and functional before attempting rigid tap.

Inspect tap for wear or damage and verify correct tap size and type for material being machined.

Verify pilot hole diameter is within specification for tap size (typically 85-90% of tap major diameter).

Check Z-axis servo load meter during tapping cycle - excessive load (>70%) indicates mechanical resistance causing sync loss.

Do not run if Z-axis load exceeds 80% - risk of servo alarm or mechanical damage.

Test rigid tap cycle in air (no material contact) at programmed speed - if alarm clears, issue is mechanical binding during cut.