MACROMEDIA FREEHAND 10-USING FREEHAND Use Manual page 409

Traditionally, trapping is a prepress task handled by a commercial print shop.
Designers and production artists can use drawing tools in FreeHand to create
traps, or they can leave this task to prepress professionals.
An alternative to trapping is to apply the Spread Size printing option to objects
with Basic strokes and fills for more information, see "Setting separations options"
on page 396.
When considering how to trap your documents, begin by talking to your
commercial printer about what needs to be trapped, who is responsible for
trapping, and how traps will be created.
Whether you or your print technician apply traps to your document, your print
shop should determine the trap width, that is, the amount of overlap for each
trap. Differences in paper characteristics, sheet size, screen rulings, and press
conditions require different trap widths. The following guidelines illustrate
commonly used trap widths for printing on an offset sheet-fed or web press. If you
resize a document, you may need to resize the traps.
Note: