Asymmetric line-boring bar has supports on rotated guide pad that provide freedom to enter and exit guide part, even when passing through raw bores, while geometry allows feeding bar through raw bores on eccentric path. Such boring offers support on both ends of tool without necessitating expensive lift functions, obstructive counter bearings, or critical mechanisms inside tool. Also, complete feed-in and feed-out moves can be done at increased feed rates on conventional machining centers.