WE ARE HAVING MORI SEIKI SH400 MSC 518 WITH FANUC CONTROL. SUDDENLY WE ARE FACING ISSUE IN B AXIS WITH THE TABLE CHANGING ITS POSITION TO A TAPERED POSITION OF 0.3 AFTER EVERY PALLET CHANGE.

THE MACHINE CHANGES PALLET FOR SETUP CHANGE THEN WHEN THE TABLE IS PALCE BY MACHINE IT RESTS IN A TAPERED POSTION OF ALTEAST 0.1 TO 0.3 MM.
WE HAVE TRIED TO TIGHTEN THE BAXIS MOTOR COUPLING BUT THE MACHINE WORKS FINE FOR A FEW HOURS THEN AGAIN SAME ISSUE
IN ROUGH BORING THE MACHINE LEAVES A STEP INSIDE THE BORE IN SOME PCS EVEN AFTER THE TABLE BEING IN CALMPED STATE