The XYZ controllers assign an individual track to the X, Y, and Z components of the position, rotation, or scale of an object. However, the controllers always assign three keys (one for each axis), by default.
In previous versions of 3ds Max, you had to manually edit the keys in order to create explicit axis keys. However, there are now actions available from the Customize User Interface dialog that let you create explicit keys with the touch of a button.
When an explicit key is created on an axis, any keys on the two remaining axes (at the selected time) will be deleted.
An explicit axis key can only be assigned to objects that already have an XYZ controller assigned to their position, scale, or rotation tracks.
You can also use Keyable Icons to turn on or off tracks for editing. This allows you to set keys on only specified PRS X, Y or Z axes as well. See Keyable Icon .