Hi @yaronw3,
Is it possible that this is problem with the PDF Reader application you are using? Sometimes hairlines can get lost at certain zoom levels. I, like @Alfred.NESWADBA, would like to see your drawing file (along with a plot style if you use one) and the resulting PDF. This will help me to better understand what might be happening in this process.
Please select the Accept as Solution button if my post solves your issue or answers your question.
John Vellek
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