1. In the Machine Definition Manager, click the Edit axis combinations button.
2. If necessary, select the desired axis combination.
3. Click Reference Points.
4. Set default reference positions for ID and OD work, for either approach or retract moves.
Because these are specific to the axis combination, you can even define different locations for main spindle/subspindle, and upper/lower turrets. Important—because you are in the machine definition, the coordinates in the above dialog box are in world X-Y-Z coordinates, not lathe X-Z coordinates.