I have been trying to play with this too for a little while.
But sadly, I'm encountering similar problems as you are.

I think you do a 3D capture through the drop down menu in adobe.
What you do is turn your cad program settings to OpenGL, go to 3d capture, click back on your cad program and hit print screen.

And by some magic, it instantly imports the 3d model.

Export as an .ifc from ACAD 2010
Select canvas in Adobe Pro Extended 9 click on browse instead of capture and select your .ifc file.

If you have ACAD 2009 there is no export as .ifc option. You might want to try to export as .stl. Will also import about 30 other file types including 3ds, iges, pro e, etc. I have done the .ifc version successfully from revit to adobe. Have not tried the capture command.

thanx.. i was able to figure it out from acad 2006 ...I pretty much rebuilt the model and every so often I would export it to see if it worked ..and it did, until i got to a certain area that was to complex for the export ..so I basically simplified that area

Wurdan, how do you import a 3ds file into PDF?

My model needs to be partly transparent and ACAD doesnt do transparency (that I know of).

I'm noticing that I read your 6 as a 9 in your original post. Is that dyslexia?

You can import any of the file types that are compatible with Acrobat 9 pro ex in the same fashion as you would import the .ifc file using the 3D tool.

microstation does it.. probably some other BIM programs. you just go to print 3d-pdf and done. they're surprisingly small

works like charm with rhino