I have seen a number of discussion group posts talking about this issue now. Users open a DWG using Autodesk Design Review 2010 and some, if not all, lines are showing up with a thick line width.
AutoCAD or AutoCAD based applications provide users with an option to create layouts in the DWG. Within the layouts decisions can be made as to "how thick" the lines should be or what line width they would like to apply. It also provides an option for the paper size settings. These DWG layouts are turning into sheets within DWF files. As a result of this - DWF files can have one sheet for DWG model space and none, one, or more sheets for the DWG layouts.
It should also be noted that Autodesk Design Review makes use of DWG True View, when loading a DWG and effectively converting the DWG to DWF. As a general rule - the default settings for model space or the layouts are such that the lines come out really thick.
The issue can be resolved by choosing the same size lines on a bigger piece of paper or thinner lines on the same size piece of paper. Changes have to be applied to the DWG. User who do not have access to AutoCAD or the AutoCAD based application can use DWG True View.
Note: DWG True View is a viewer and does not apply changes to DWG files permanently. As such, it should only be considered a temporary workaround.
Steps Needed Are:
1. Load the DWG into DWG True View.
2. Make the changes as outlined in http://dwf.blogs.com/beyond_the_paper/2006/12/common_dwf_publ_1.html.
3. Publish the DWF.
4, Load the DWF in Design Review.