Import 3D Cad Files

[djn]

Does anyone know how to crop a 3D AutoCAD file that has been imported into Revit. What happens is I import the cad file into the model, then when I open the second floor, for instance, I see the whole imported file not just the elements defined by the crop region for that floor. Which makes it pretty much useless to work with.

[Teresa.Martin]

Hi!
In response to your question about imported 3d Autocad files and visibility.
You can control the visibility in a number of ways.
1) Using Visibility Graphics and turning layers on/off (imported categories).
2) You could import the 3d file into a massing family. You could then use created walls,floors, curtain systems, roofs by face under the massing tab.
3) You could import the 3d file into its own family type, such as general model or plumbing fixture depending on what it is you are trying to accomplish. You can then tweak the visibility for each view (plan, front, side, etc.).
I hope this helps!
Best regards,

[djn]

Thanks for the response. I think I should be more specific in what I trying to accomplish. I have a 3d structural autocad file that I am in trying to link to my model as a background, see attachment "Structural Model". When I do this the cad file doesn't pay any attention to the view range that is set up for a specific floor. For instance on the first floor plan the view range is set to cut 1'-0" above the level and look -4'-0" below the level. Yet when I look at the first floor plan with my imported link turned on I still see the framing for the second floor, third floors on that plan. Like wise if I look at the second level I see the foundation and third floor framing from the autocad even through the view range is set. The attachment called "Revit Model" is a screen shot that shows the first floor plan, with 3d autocad file turned on, and set to halftone. You will see that upper floor framing shows up. If there is a way to crop the 3d autocad file to not show these elements that would be great, even better would be if there was a way for the autocad file to pay attention to view range set up by floors. I tried you suggestion of importing into a generic family. That seem to give me better results, but I lost the ability to turn levels on and off, and I don't want to have to create a new family every time I get a new background.

[al]

We have the same problem -- I'd really like for this to work. No solutions here.

[david.metcalf]

I don't have a 3D model to test it with, but can Plan Region address this issue?

[al]

Just tried - doesn't seem to make any difference with a plan region.

[JamesVan]

To accomplish integration of a 3D CAD file (DWG/DXF/DGN), you must create either an in-place family or an RFA file in a category which can be cut (look under Settings-Object Styles for those with both Projection and Cut values). In this case, I would create a Structural Framing family. While you are in family mode, link in the CAD file. When you finish the family, it will behave (view/cut) like other Revit geometry.

[Scott D Davis]

you are also in wire frame mode...changing to hidden line will help to see whats really going on.

[al]

I am afraid these options don't work for me - in-place or RFA. I have tried this from time to time without any success. I wonder if it has something to do with our Autocad files.

[djn]

If I change to hidden line mode in the first floor plan, what I would see is the roof slab because the whole building is being shown. In order to see the first floor framing you have to look at it in wire frame mode.

As far as creating a generic family of the model. I did get that to work, but there some problems with that also.

1. You lose the ability to turn levels on/off from the imported cad file.

2. You lose the ability to have the cad file come in "origin to origin", you actually have to place the family component where you want it. Which would become very problematic when trying to see what direction columns or grids have shifted.

3. You lose the ability to link the cad file. When I get new backgrounds I have to re import the cad file into the family.

[Scott D Davis]

1. You lose the ability to turn levels on/off from the imported cad file.

2. You lose the ability to have the cad file come in "origin to origin", you actually have to place the family component where you want it. Which would become very problematic when trying to see what direction columns or grids have shifted.

3. You lose the ability to link the cad file. When I get new backgrounds I have to re import the cad file into the family.
1. In Visibility/Graphics, you can still turn on and off layers/levels of imported CAD/DWGs by looking into the Imported Categories tab, and then look for the "Imports in Families" section. Expanding this list revelas all the layers that are "embedded" in imported DWGs in families.

2. With some extra "references' you can still get a family placed at the origin. There is some other topics here regarding "Finding the Revit origin" that will help, but bascially, you need to mark in your DWGs where 0,0 is with a circle or crossing lines before you import them. Then you can find the origin in your project by linking in a DWG at origin to origin by only having a mark at the 0,0 in the Linked file. Insert the family with the "reference mark" and align it with the "project origin".

3. Correct....no Linking into families. Haviong the DWG imported into a family is the only way Revit understaands how to "cut" the 3D DWG.