D. E.Dan's advice will break both the primary and the secondary beam. If you want to break only the secondary beam, use the Special Tools Tool.
In the Special Tools Tool palette, look for the Secondary Beam Break Tool.
Once you in the first measure have broken the beams the way you want, you can copy the secondary beam breaks to the other measures:
Mass Mover Tool
Mass Mover menu: Copy Entry Items...
And don't forget the power user way of copying:
Select the area you want to copy,
hold down the secret modifier key combination (Windows: Ctrl-Shift ; Mac: Option-Shift),
and click where you want the copy.
Peter
