Is there a technical explanation for why outline strokes that are not aligned centered are converted into a filled object during PDF export?

What application is being used to perform the actual path cutting? When I think of cut paths I usually think of them in terms of large format printing and then die-cutting after the print is laminated. A large format RIP application would be involved. Of course there are other use cases where cutting after printing is involved. In either case any third party applications may have trouble properly importing PDF files with off-center line strokes unless they can support the latest PDF file versions. Some limitations may still be involved.

Is there a reason why the cut path has to be made off center? In projects where I need to use a cut path I have the path set exactly where I want the plotter blade or routing bit to cut. If I need bleed going past the cut path I’ll have separate objects filled (or stroked) for that bleed to be printed. I have to assign cut path strokes with a specific spot color (usually “CutContour”).

The stroke should still remain visually. Non-centered strokes just become a separate object. 

Try copying the art and using the Outline feature on the Pathfinder panel. With a little editing, it can make a good cutline.

Hi @Franziska2202788319tf,

Thanks for reaching out and for raising this question.

To help us better understand and investigate the behavior, could you please share a screenshot from Illustrator showing the original object along with its stroke/alignment settings, and a screenshot from Acrobat showing how the same object appears in the exported PDF?

Please also share a screenshot of the PDF export settings used in Illustrator for reference.

This will help us better understand the exact workflow and behavior you're seeing.

Thanks,
Abhishek

​@Franziska2202788319tf I believe that is caused by the origins of Illustrator. Illustrator and later PDF were based on the Adobe PostScript page description language, which has only the center aligned stroke. Illustrator added the align Inside and Outside stroke options later, which have no equivalent in PDF.