Editing PDF and Other Drawing File Formats in AutoCAD

By Bill Fane

AutoCAD can create, open, edit, and save a number of other file formats, including several other brands of CAD software. On the Application menu, look at the options under Open and under Import, and then click the Files of Type drop-down list to see the list of supported formats.

AutoCAD 2017 added the capability of editing PDF files. From a practical point of view, this is viable only if the PDF was created by exporting a drawing file from AutoCAD or another CAD program. Yes, AutoCAD can edit a PDF that came from a Word document, for example, but you don’t want to do that.

To edit a PDF drawing, do this:

  1. Open a new or existing drawing file.
  2. On the Application menu, choose Import → PDF.
  3. Press Enter.
  4. Browse to and select the desired PDF file using the file dialog box that has appeared.
  5. Click Open. The Import PDF dialog box appears.
  6. Click OK. For your first try, you probably want to go with the defaults.
Import PDF dialog box
The Import PDF dialog box.

Magic! This looks exactly like the original drawing that was used to create the PDF! Even all the text, dimensions, colors, layers, and linetypes are correct.

Yes, AutoCAD can now edit a PDF file, but (and it’s a big, uppercase, bold BUT — not to be confused with a big butt) before you get all excited at the prospect, you may want to consider the following discussion of some of the limitations. It’s possible that these may be inherent in the PDF format or with AutoCAD’s capability to analyze the file or both.

First, all complex object types have been exploded to their basic constituents. For example, all block insertions, hatch patterns, text, and dimensions have been reduced to a bunch of individual polylines. That’s right, every line segment in a complex hatch pattern has become an individual, independent polyline segment. Similarly, dimensions get exploded to polylines and text, and are no longer associated with the original definition points.

Worse yet, all text is exploded to individual characters. TrueType fonts survive, but the individual characters in AutoCAD’s SHX fonts get redefined as a bunch of polyline segments.

There’s more! Curves such as splines and arcs also end up as a multitude of straight polyline segments.

Ah, but here is the worse. There is a great need for accuracy in AutoCAD drawings. Unfortunately, the PDF file doesn’t share those sentiments, and so most objects seem to come in with sizes that vary from the original drawing in the third and fourth decimal place. This may not sound like much, but you will now find that two lines that are supposed to intersect each other or touch at their ends probably don’t.

Other than that, PDF editing is perfect.