How to butt, or attach, a balloon to the panel border.
Butting balloons is an excellent way to conserve space in a tight panel. Use them only when necessary, though, as they can reduce the margin of error available when the lettering is merged with the finished artwork.
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1. The top line of text on a butted balloon should be wider than usual, but still a little narrower than the line directly below it. Draw the balloon so it overlaps the panel border.
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2. Using the box tool, draw a box that covers the area you want to remove. Make sure the edge is centered on the panel border.
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3. Send the box to back using Object > Arrange > Send to Back (command-shift-[). Select both items, and click “Minus Back” in the Pathfinder palette.
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4. Select the balloon(s) and tail, and click “Unite” (“Merge” in Illustrator 10 and above) in the Pathfinder palette, and you’re all set.
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5. Before finishing the page, be sure to zoom way in and make sure all your balloons line up exactly with the panel border.