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Illustrator Tutorial - Cutting Letters In Half
Branching Point to Everything Else on ArtistMike.com
Contact Mike at: mike@artistmike.com
After you have slected everything you find the "Pathfinder" menu, click the first button on the bottom row. It looks like a exploding "egg"
The result of clicking the button will be a set of shapes that you can move apart. The cut will be based upon the position of the line that you drew on the letters.
 
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