Check out this CATIA V5 tip: http://www.ignitecast.com/p/jGYVAaI4zt/
I created and uploaded this Ignitable to IgniteCAST.com to show you how to create Isometric Breakout Sections in CATIA V5 r18, This tip is for intermediate CATIA V5 users using the drafting workbench, so I hope you find it useful.
Steve