An old CNC machining center with Fanuc 6M CNC control system, the X axis swings slowly to both way, as long as the work table moves to the middle of the travel.

As the machine runs normal when the table on other position, so this is not the problem of CNC parameter, servo driver or mechanical parts.

Considering the machine is very old, the connection between the machine parts and the servo driver system could be changed, if they not match well would cause the regional swing of the servo system, and this problem could be solved by setting the S6, S7, S11 and S13 setting ends.