Linked CAD file visibility problems

[TiaAI]

Hi,

I'm quite new to Revit and am having an issue with the visibility of linked CAD files. I've tried searching the forums for someone who's had a similar issue but cant seem to find anything that helps.

I have linked several Autocad plans to my revit floor plans to give some context to the drawings. However a short while after the CAD files are loaded and I've set up the visibility/ graphic overides for the line styles, the content of the CAD file partly disappears?? I am left with just one visible CAD layer which hapens to be the title block frame, so I can see the extents of where the file should be - just nothing else. (I've attached a jpeg to show you what this looks like - the pink box is the title block frame I was refereing to)

Also the extent of the file is huge even though in CAD it is not... I've double checked by using zoom extents in the CAD file and there are definately no lines hiding miles away. A third issue is that in Revit it won't let me select the linked CAD file.

I have tried reloading the files in the Manage Links tab but this doesn't help. The only thing that has worked previously is to remove the files and reload them. Although this only works for a while before the issue starts again and it also mean I have to go through and set up my imported line styles again which is time consuming!!!

Can anyone please help?!

Many Thanks

[Alisder.Brown]

TiaAL

This is an issue you may find with alot of AutoCAD files. 

Best practice for linking CAD into Revit is to copy/paste the AutoCAD stuff into a FRESH .DWG file and save it. Then link this file in.

This method ensures you will be linking in a clean fresh CAD file and will get rid of annoying issues like the ones you are comming across.

" I've set up the visibility/ graphic overides for the line styles" what do you mean by this? Are you going through every layers settings within Revit and changing how they look?

Try the above method, it it the best way to ensure clean files.

Hope this helps

[TiaAI]

Hi Alisder,

Thanks for your reply. I tried creating a 'fresh' autocad file and reloading it but now all the layers have disapeared - so now I cant see the title block layer that was visible previously?

" I've set up the visibility/ graphic overides for the line styles" what do you mean by this? Are you going through every layers settings within Revit and changing how they look? - Yes! that is exactly what I've been doing. We dont have any office standards for importing CAD layers to Revit so I have been just overiding relavent imported layers so they look the way I want them to in my Revit plans...

[Alisder.Brown]

Are you specifying your settings when you choose the file to link in? see attached image. You need to make sure you have the correct import settings or you can hit some major issues. 

Would maybe be easier if you could share the CAD file and i can see if i have the same issues?

Regards

[TiaAI]

Hi,

Yes all my setting are as in your attached image apart from I have chosen it to preserve the CAD colors and I have been setting the positioning to manual as the file extents keep coming in so big that I keep losing the drawing if I dont.

I just tried linking my 'fresh' CAD file into the revit plan again and got this error message (see attached). So the CAD drawing is definately there even if I cant see it. If i click continue the drawing loads but then again I cant select it to re-position it into the correct place...??

I've attached one of the CAD files in question, hopefully you'll have more luck than me! 😞

[Alisder.Brown]

Could you walk me through the exact process you are using to link the file in?

I just done it and it works perfect. Does not seem to be any issue with your CAD file

This is what i done:

1. In my plan view in revit got to "Insert" tab > "LINK CAD" 
2. Find your AutoCAD file
3. For the Settings for import SEE IMAGE i have attached (same as you i think)
4. Click to place the file
5. Edit some visibility graphics

Works perfectly fine, i am having no graphical errors or hiccups :S

When you are overriding the graphics, are you doing the following:

1. In whatever view you need > Visibility graphics  > "Imported categorys" tab > Expand your CAD file from the list
2. Click inside the "Line" box for each layer you wish to change and change lineweight etc
3. Apply + OK

Make sure you are not accidently unticking the layers from the visibility graphics or the whole file for that matter, as this will turn their visibility off.

Also, when you are linking in the CAD file, make sure you set the import units to whatever they have been drawn in the .DWG file.

See attached image for settings i used.

[TiaAI]

Hi,

So I think it was an issue witht e CAD file before i started with the 'fresh' file as you sugested. I started again by removing all the old links and re-linking the new clean CAD drawings and now they seem to be working fine - fingers crossed!

This is how I set up the 'fresh' CAD drawing fo anyone who might be having similar issues;

• Copy and paste everything into a new metric CAD file without a template with world co-ordinates with base point as 0,0,0 – Select ‘New’ the ‘Drawing’, a box will pop up then select the arrow next to open and select ‘Open with no Template – Metric’ (see attached image)

• Ensure no layers are hidden, frozen or locked
• Explode all blocks (exploding hatches can also help)
• Purge everything
• Do a zoom all / zoom extents to make sure there aren’t any objects off in the distance.

[TiaAI]

Hi,

So I think it was an issue witht e CAD file before i started with the 'fresh' file as you sugested. I started again by removing all the old links and re-linking the new clean CAD drawings and now they seem to be working fine - fingers crossed!

This is how I set up the 'fresh' CAD drawing fo anyone who might be having similar issues;

• Copy and paste everything into a new metric CAD file without a template with world co-ordinates with base point as 0,0,0 – Select ‘New’ the ‘Drawing’, a box will pop up then select the arrow next to open and select ‘Open with no Template – Metric’ (see attached image)

• Ensure no layers are hidden, frozen or locked
• Explode all blocks (exploding hatches can also help)
• Purge everything
• Do a zoom all / zoom extents to make sure there aren’t any objects off in the distance.