Machine - V.M.C. - KIA KV25
Control - Fanuc 0M
The problem came out suddenly, without any change on machine/control.
When machine starts to rigid tap, it immediately starts buzzing very loud.
It makes few threads (aprox. 3 out of 10 on one workpiece), and than feed and spindle stop (at R level i assume), but it is still buzzing. When I push Reset button, buzzing stops.
Buzzing is heard also when spindle doesn't rotate, between holes.
Buzzing can be described as on very bad bearings.
Buzzing is not heard when rotating with M3 at any speed.
Spindle motor is connected to spindle directly, with hard connection.
Rigid tapping, with same nc code (M29+G84) worked well before.
Now if I replace M29 with M3, it works OK (without buzzing), but it is not rigid (synchronised) tapping now.