One of my colleagues created a 7MB PDF from a CAD file today. This in itself is a sure sign that something was wrong with either the PDF or the generation of it. So after crashing Acrobat in an attempt to reduce the file size, I reviewed the PDF to see what might be the issue.
One part of the PDF took a while render in Acrobat which pointed out that the PDF contained something with dense information that was taking a while to load. Usually this is an image or some large single object like that.
Once I reviewed the source I discovered that there was no images attached to the file. So this was not the issue.
A quick Audit revealed 4 errors but this was not the issue either.
So, process of elimination. What is causing the issue. Delete various items from the sheet to see which item is cuasing the issue. I usually start with viewports.
This was done by deleting one at a time and creating a PDF each time. Each time I noted that the PDF was taking ages to generate, which also is a sign that something is not quite right.
Once I found the viewport I could look at that part of the model to see what the issue could be. From experience hatches can be problematic and it turned out that my colleague had created an ultra dense hatch that looked like a solid. Once changed to a solid hatch (which I don’t like, but that’s another story), the file printed file.
Interestingly AutoCAD sometimes pops up a box saying to convert these to solid or increase the scale but it did not do so on this drawing, so don’t rely on that to tell you if there is an issue with ultra-dense hatches.