Misalignment represents one of the leading causes of premature CNC router drive train component wear and failure.

Usually alignment problems begin with the design and fabrication of the machine frame itself. It may not be flat, straight or parallel enough for drive train components such as linear bearings and linear actuators to move properly. For an example, mounting surfaces may have variations in flatness (high spots) that will read through to the linear bearing rails and/or system racks. Or, machining inaccuracies in frame mounting surface may make it difficult, if not impossible, to mount bearing rails and system racks parallel to one another in the horizontal axis, vertical axis, or both.

Whatever the type of misalignment the result is uneven loading of drive train components. Including excessive point loading. At some point, even before catastrophic failure, uneven loading will cause binding, excessive friction and sluggish, rough motion.