Unprintable PDF's because of Flattening

[Anonymous]

I work for a small Civil Engineering firm. We have been publishing AutoCAD drawings using the "DWG to PDF" print driver for 3 years on Civil3D 2015. All of the sudden we've had multiple clients get back to us and say they cannot print any pdf that we make to their plotters. We have an in house plotter that we've never had any issue with. Wondering if anyone has any ideas on why this would be happening. Is it an AutoCAD issue? Adobe issue? Print driver?

@Anonymous, john.vellek has edited your subject line for clarity: Unprintable PDF's

[pendean]

a PDF is a PDF is a PDF: what exactly are they having issues with? "cannot print" doesn't tell us much.

And can you show us one of these PDFs here too?

[Anonymous]

Pendean,

Thanks for the response. When someone not in our network tries to print one of our pdfs on a printer of theirs the file starts the flattening process and either times out or just will not begin to print to a hard copy. I'm wondering if there are any settings that are on that shouldn't be (or vice-versa) when the pdf is being created from AutoCAD. Sample pdf attached.

[Patchy]

It took awhile to print after flattening, you could try to do this before making PDF:

https://helpx.adobe.com/acrobat/kb/printing-complex-pdfs-acrobat.html

[john.vellek]

Hi @Anonymous,

I have found that if you use the newer AutoCAD PDF (General Documentation) PC3 driver you will not have the flattening process occur.

You can also avoid this in your current setup if you create the PDF with Plot Transparency unchecked

Please select the Accept as Solution button if my post fully solves your issue or answers your question.

[pendean]

Time is all they needed: like others here, your PDF did finally print. It complex and it takes a long time to print because of the chosen content in the file as John V outlined.

[pkolarik]

Our pdfs "suffer" from flattening times when processing for printing too (it's an issue we've been dealing with, and looking into for many, many years here in my company). Some things that can cause flattening (and/or slow processing times) in pdfs:

*Including "Layer Information" when you create the pdf

*Using "Lines Merge" vs "Lines Overwrite"

*Using "Transparency"

*Having pdfs (or to a slightly lesser degree, tiff/jpg images) in your dwg file

If you use "Lines Merge" (which most of our company does) you'll always have flattening occur during printing. I am, however, curious as to what John's comment about "using the newer pdf pc3 file in Autocad" is referring to. Does he mean that the 2016 version eliminates flattening even if you create the pdf with Lines Merge turned on? (we have several seats of 2016 up and running here, mixed in with 2015 seats, and I've not heard reports of flattening going away in 2016 so far)

[john.vellek]

Hi @pkolarik,

Let's give this a try if you are willing to attach some sample files for me.  I need to know your exact plot settings but I can run through all the options I see and report back to you.

[RobDraw]

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@pkolarik wrote:

Our pdfs "suffer" from flattening times when processing for printing too (it's an issue we've been dealing with, and looking into for many, many years here in my company). Some things that can cause flattening (and/or slow processing times) in pdfs:

*Including "Layer Information" when you create the pdf

*Using "Lines Merge" vs "Lines Overwrite"

*Using "Transparency"

*Having pdfs (or to a slightly lesser degree, tiff/jpg images) in your dwg file

If you use "Lines Merge" (which most of our company does) you'll always have flattening occur during printing. I am, however, curious as to what John's comment about "using the newer pdf pc3 file in Autocad" is referring to. Does he mean that the 2016 version eliminates flattening even if you create the pdf with Lines Merge turned on? (we have several seats of 2016 up and running here, mixed in with 2015 seats, and I've not heard reports of flattening going away in 2016 so far)

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It has not gone away in 2016. We've been dealing with this for quite a long time, also. Lines merge and cross hatching large areas seems to cause the longest flattening times.

[pendean]

Download a free trial of AutoCAD2017 and test it out on your own PCs with your own files, no need to post files here for others to do this for you.

Starting with 2016 Autodesk has added 4-more PDF drivers with controls right on the PLOT and PUBLISH pop-ups. They may or may not resolve the issue, I like you do not use the setting you've outlined not to use.

[john.vellek · Accepted solution]

HI @pkolarik,

I am adding this post as a summary of our conversations via email, in order to help others with this issue.

You are experiencing problems in printing PDFs created in AutoCAD. During the print process, you see that your PDF Viewing/editing software has to Flatten the PDF before it can send to the hardware printer.

The features that trigger this action are transparency related (such as line merge). This will occur in all PDF drivers as the flattening is a result of how the PDF format is defined by Adobe.

Here is a link which can provide greater detail on the transparency issue and how users might be able to reduce Flattening time using presets in their PDF editing software.

[Chad.millard]

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@john.vellek wrote:

HI @pkolarik,

I am adding this post as a summary of our conversations via email, in order to help others with this issue.

You are experiencing problems in printing PDFs created in AutoCAD. During the print process, you see that your PDF Viewing/editing software has to Flatten the PDF before it can send to the hardware printer.

The features that trigger this action are transparency related (such as line merge). This will occur in all PDF drivers as the flattening is a result of how the PDF format is defined by Adobe.

Here is a link which can provide greater detail on the transparency issue and how users might be able to reduce Flattening time using presets in their PDF editing software.

---

This is not accurate.  Any .pdf created using the Adobe or Bluebeam .pdf driver, regardless of content in the .dwg, are already flattened and do not have this issue.  This only happens with Autodesk .pdf drivers, and only in AutoCAD.  
Revit does not have this issue with it's native .pdf driver, and I use hatching in it all the time.

[pendean]

Actually, you're not fully accurate either.

Non-AutoCAD drivers flatten output by default from AutoCAD: AutoCAD PDF drivers treat these transparency/line-merge settings the same way other graphics programs like Photoshop and Illustrator do, but unlike those other software, it just doesn't ask you to flatten the PDFs first.

REVIT handles sheets in a completely different manner from the model: your apples/oranges comparison, because you assume Autodesk software teams right one code for all software, is inaccurate as well.

[Chad.millard]

uh.... the first part of your statement is what I just stated?

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@pendean wrote:
Actually, you're not fully accurate either.

Non-AutoCAD drivers flatten output by default from AutoCAD: AutoCAD PDF drivers treat these transparency/line-merge settings the same way other graphics programs like Photoshop and Illustrator do, but unlike those other software, it just doesn't ask you to flatten the PDFs first.

REVIT handles sheets in a completely different manner from the model: your apples/oranges comparison, because you assume Autodesk software teams right one code for all software, is inaccurate as well.

---

[RobDraw]

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@Chad.millard wrote:

uh.... the first part of your statement is what I just stated?

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@pendean wrote:
Non-AutoCAD drivers flatten output by default from AutoCAD:  

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He added, "by default", implying that it is a setting and, if I remember correctly, AutoCAD's PDF driver can be set to do so also. It's that or flatten the PDFs to another PDF and send the flattened PDF to the plotter.

[Chad.millard]

If you can set AutoCAD's pdf driver to that - I would really like to know where that setting is at.  I've spent about 8 years looking for it.  The Adobe driver doesn't keep shading or solid hatches looking right.  The Bluebeam driver has it's drawbacks as well.  The AutoCAD driver looks good, but has the flattening issue.  Even running it from AutoCAD and then running the pdf through Adobe - it doesn't work all that well.  Unless you have the newest version of Acrobat that flattens the .pdf inside the software.

[RobDraw]

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@Chad.millard wrote:

If you can set AutoCAD's pdf driver to that - I would really like to know where that setting is at.  I've spent about 8 years looking for it.

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It's been so long since I've had to deal with this issue, I can't remember how it got fixed for us but I've since moved on from that company and have not had to deal with it since. Something is coming to mind though and it has to do with searchable text and SHX fonts in the PDF.

Yup, this might be it:

https://knowledge.autodesk.com/support/autocad/learn-explore/caas/CloudHelp/cloudhelp/2016/ENU/AutoC...

Good luck!

[ahameed]

Print your PDFs with "Print as image" option enabled. With this option no flattening occurs. It works for me at least.

[PSharpKPQPX]

still stuck in flattening in 2024!
can't print as image as i need to orint as 2 a3 page poster size. 

[pendean]

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@PSharpKPQPX wrote:

still stuck in flattening in 2024!
can't print as image as i need to orint as 2 a3 page poster size. 

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"flattening" in PDF has a lot to do with the settings you chose in the PDF driver for output, rarely anything else.

These are discussed starting in message #7 where you poste, explore them when you get a chance.

And show us all the settings to turned on please if you are still unsure.