According to Wikipedia a “bleed” “…refers to printing that goes beyond the edge of the sheet before trimming.” One of the most common problems we face when we receive “print-ready” files from our customers is that they do not include a bleed in the document when they send it to us. This give us, as the printer, two options: 1) getting a new file from our customer, which takes time, or 2) short trimming or under sizing the final piece, resulting in a final piece not exactly as the designer intended.
The challenge really comes down to the issue that the printing manufacturing process is not an exact science, there are just too many variables that influence the final piece. Some examples are, the type of paper, the grain of the sheet, how much ink is on the sheet, the speed it is ran, how much moisture is in the paper and in the press room environment, the sharpness of the cutter blade, the list goes on and on. Since a lot of these factors are not controllable by the printer, we find ways to work around them, thus the concept of “a bleed”.
Bleeds are commonly sized anywhere from 1/8 (.125 in) to 1/4 (.25 in) of an inch based on the type of printing and the requirements of your printer. Remember that anything outside the trim area will be cut off and not show up in your final printed piece. If you fail to provide bleed information (and crop marks) your finished piece could show a thin area of white on the edge, thus requiring the printer to undersize the final piece to get rid of the line. (I will cover how to setup your InDesign file in my next post)
Without a bleed (note the white line)
With a properly setup bleed
Before the bleed was cut off, note the green extends past the trim marks.
