Mark Douglas has a nice post on the the new DWF attach feature in AutoCAD 2007. It allows 2D DWF's to be attached, like xrefs, for use as a background. He also details a clever workaround to use this feature to attach PDF files if that is all you can obtain.
I tested the accuracy of DWF attach by inserting DWF’s back into their source file and was impressed. Of course, it will depend on the precision used when the DWF is generated. See below for links to earlier posts on how to control, & the impact of increasing, DWF precision.
- Earlier posts on DWF Precision:
- Why high DPI settings will not greatly impact file size.
- AutoCAD DPI to DWF precision in Metric and Imperial
- This post where I tested DPI settings with a production file may also be of interest: "Real World" DWF Resolution Findings