import dwg problem

[Cheuk Ling]

Hi,

I got problem in importing the attached dwg file (it's only one of the
examples).
If you check the dwg file in AutoCAD, everything looks alright.
But after link/import to Revit, all lines (original straight )
turn into zigzag shapes ! Anyway, when you use pick tools
to hover over those strange lines, they seem to be straight.
Anyone can provide explanations and solutions on that problem ?

[Scott D Davis]

Your drawing is being scaled incorrectly upon import. Check the import settings. In Revit, its really small and thus becomes a jagged mess.

[Cheuk Ling]

thanks Scott,
I realize the problem comes from the co-ordinates .
The AutoCAD structure is drawn at true co-ordinates readings.
I found that most of this kind of drawings could not be imported
into Revit properly (will turn to Center to Center sometimes,
but it in turns change the co-ordinates)
I just want to know is there a drawing limit (by factory) set in Revit,
just like the design plane in Microstation .

thanks in advance

[Steve_Stafford]

I took a look at your file. Support might like to take a look at it. It appears to be using millimeters for units. I opened a default template and changed my units to millimeters too. Then I imported the file using origin to origin being careful to specify millimeters for import units scaling. Revit complained about not being visible in the view of Level 1. When I looked at your file again I found that not all objects were at zero elevation. One text object was below, so I moved it up. Imported again and it showed up without a message.

The linework in the dwg is represented poorly in Revit and only the dashed linework using the Acadiso linetype styles in Acad. I tried using the Acad.lin file to create the linepattern and noticed that when I did the dashes also appear slightly skewed in Acad, not as badly as in Revit with the Acadiso.lin based line patterns though.

If the plan is rotated orthogonal in the acad file Revit represents the linework better. It doesn't like the angle of bldg as it is drawn in acad and the distance from 0,0.

The coordinate system does factor in because if the plan is moved closer to 0,0 the linework looks more normal. Any particular reason the dwg plan is 1,171,237,293 mm (1,171,237 m) (1171 km) from 0,0 ?

[Scott D Davis]

IAny particular reason the dwg plan is 1,171,237,293 mm (1,171,237 m) (1171 km) from 0,0 ?
Ah yes! Thats it! We had the same problem in our office, and I had thought that it was a scaling issue. Steve's post jarred my memory. I opened it in AutoCAD, moved the geometry closer to 0,0, and then re-imported into Revit, and everything was fine.

[DanielleAnderson]

Take a look at THIS (http://forums.augi.com/showthread.php?t=6260&highlight=autocad) thread and THIS (http://forums.augi.com/showthread.php?t=5302&highlight=autocad+origin) thread... might give you some extra pointers and let you know you're not alone out there. :)

[Cheuk Ling]

The coordinate system does factor in because if the plan is moved closer to 0,0 the linework looks more normal. Any particular reason the dwg plan is 1,171,237,293 mm (1,171,237 m) (1171 km) from 0,0 ?[/QUOTE]
Thanks for all replies and I have looked at those relevant threads.
I agree that moving the dwg file closer to 0,0 would solve the problem.
But it's not effective to do such thing for each importing dwg file and
each updated version throughout the project stages.
This co-ordinate system is the real (true) readings using in my region.
In order to have a better communication with other parties,
it's vital to keep this system strictly.
I 'm still waiting an answer for the drawing extent / limit preset in Revit ?
There must be a limit, otherwise Revit need not have to shift the content
to centre to centre.

[swalton240189]

In Revit 2011 I'm having a similar issue, where lines, circles and squares in the CAD link are getting skewed and jumbled. Revit Units are millimeters and The CAD units were set to millimeters (but should have been meters) So I changed the ACAD to meters but that didn't help.

The file is only 582meters across the diagonal.

Any ideas?