A properly created print-ready PDF file should include a trim box definition within the document structure. Some methods of PDF creation do not include this important element. To add the proper trim box definition to an existing PDF file, follow the instructions below:
To add a trim box, open PDF in Acrobat. Select Document / Crop Pages. Change crop box to trim box. Add the necessary trim to all sides (This amount will depend on how large the bounding box is). Click OK and save file.
If you have multiple PDFs that require the same trim box definition, batch processing can be used.
In Acrobat go to Advanced/Document Processing/Batch Processing…
Choose New Sequence, name it: Add Trim Box, And hit OK.
Click on Select Commands… Scroll down to Crop Pages and add it to the sequence.
Highlight Crop Pages on the right, and choose Edit.
Change Crop Box to Trim Box, and under Constrain Proportions, select the desired amount to crop on each side, making the trim box final trim size. Choose OK and OK again…
On your Desktop, create a folder called “Originals” containing all the PDF’s that require trim boxes. Also create an empty folder call “Trim Box”.
1. Be sure Crop Pages is in the Menu…
2. Choose “Selected Folder” and choose the “Originals” folder from your Desktop.
3. Choose “Specific Folder” and choose the “Trim Box” folder on your Desktop.
Select Run Sequence, verify the destinations are correct and Crop Pages is selected, and choose OK.
The new PDFs, with a trim box definition, are now in the “Trim Box” folder on your Desktop.