topic Re: Linked CAD file changes position in Revit Architecture Forum

Linked CAD file changes position

tmccar — Tue, 18 May 2021 12:41:27 GMT

I have a site layout of a building in which I have a linked CAD file which has the map of the area. When I save this file and close it, it changes the orientation of the CAD file and to fix this, I change the view orientation to "Project North", than re-load the CAD file link, change orientation to "True North" (and possibly adjust the crop region also).

But it loses the orientation every time I save and exit. Is there a way to fix this?

Re: Linked CAD file changes position

Anonymous — Tue, 18 May 2021 13:16:38 GMT

@tmccar, the orientation of the original view where the DWG file was linked must be Project North. This view must also remain Project North throughout the life of the project.

Re: Linked CAD file changes position

barthbradley — Tue, 18 May 2021 15:25:18 GMT

This shouldn't be happening. Are you sharing positioning between the two files (e.g. are they linked via Shared Coordinates)?

Re: Linked CAD file changes position

tmccar — Tue, 18 May 2021 16:17:53 GMT

Yes I usually click "Acquire coordinates" on the linked file.

Re: Linked CAD file changes position

barthbradley — Tue, 18 May 2021 16:58:43 GMT

I don't know exactly what your workflow is, but the process to set up Share Coordinates is to first move the CAD Link into the correct position and orientation relative to the Parent Project's Building. Once the Link is positioned correctly, that's when you Acquire Coordinates and SAVE the Parent Project AND the Shared Site back to the Link CAD. Sounds like you may be missing this step.

NOTE: You cannot save the Shared Site back to the Link if it is open for editing or read-only.

Re: Linked CAD file changes position

tmccar — Tue, 18 May 2021 19:41:21 GMT

Ok - that's the workflow I normally follow, up to the "Save the shared site back to the CAD link" - how do I do this step?

Re: Linked CAD file changes position

barthbradley — Tue, 18 May 2021 20:38:11 GMT

Just save the Revit Project File as you would normally do. You'll be prompted to save the Shared Site during the process. Click "Save".

To verify, you can unload the Link and open it directly, type UCSMAN and see if a "Revit60..." Named UCS is listed.

Re: Linked CAD file changes position

tmccar — Tue, 18 May 2021 20:48:55 GMT

When Is ave the project, I don't get any prompt to save the Shared Site.

By "Shared Site" I guess you mean the linked Autocad file which appears under Revit Links - CAD Formats. is that correct?

Re: Linked CAD file changes position

barthbradley — Tue, 18 May 2021 21:00:21 GMT

Okay, so it sounds like the position is already saved. Does the CAD file have a "Revit60"?

...the other issue might be that you have a number of Revit60s in the CAD. Do you?

Re: Linked CAD file changes position

tmccar — Tue, 18 May 2021 21:09:42 GMT

No, it only has the World UCS

Re: Linked CAD file changes position

barthbradley — Tue, 18 May 2021 22:49:00 GMT

@tmccar wrote:
No, it only has the World UCS

Okay. Let's go about this instructional another way. Open the RVT file with the Linked CAD. Is the CAD Link where it should be? I'm guessing it is. Now select the Linked CAD, press "Shared Site" under its Properties and then press "Change" next to "Record Current Position...". Now press "Duplicate" (under "Location Weather and Site": "Site" tab) and create New Site name (call it "Shangri-La" for this exercise) and press "OK" -- and "OK" again to close out of the "Choose Site" dialog box. Now, go to Insert: Manage Links: CAD Formats and highlight the CAD Link line. Press "Save Position".

Now Remove the Link, Save the RVT Project and Close it completely (just go with me here). Now Open the CAD File, Type "UCSMAN". Do you see "Revit 60 -Shangri-La"? I'm sure you do. That's your "Shangri-La" Shared Site position/orientation within the RVT you just closed out of.

Now reopen the RVT you just exited. You don't see a Link in it; right? That's because we removed it. All is not lost though. Go to Insert tab: Link CAD and insert the CAD File (with the "Shangri-La" Site) into the Project using "By Shared Coordinates" . You should now be prompted to pick a Shared Site. Pick "Shangri-La" and "OK".

Is the CAD Link now positioned and oriented exactly the right way relative to the RVT Model -- and maintain that relative position and orientation no matter what you do with the views' orientations?

Re: Linked CAD file changes position

tmccar — Wed, 19 May 2021 17:56:58 GMT

Thank you and sorry for delay.

I'm at the point of re-linking the CAD file - where is the option "by shared coordinates"? The options i have under "positioning" are:

Auto - Origin to Internal Origin

Auto - Center to Center

Manual - Origin

Manual - Center

Re: Linked CAD file changes position

barthbradley — Wed, 19 May 2021 18:02:15 GMT

Are you on a Sheet? Go to a Model View (e.g. 3D).

Re: Linked CAD file changes position

Anonymous — Wed, 19 May 2021 18:07:58 GMT

When linking in a CAD file, if you need to manually place it within the Revit file, You'll want to use one of the Manual options. Which manual option you use depends on how you'll update or use the AutoCAD file and Revit file in the future, but as a suggestion, I would always place the link Manually using the Origin of the CAD file or 0,0. Just be sure you know where this origin will be, and where it needs to go within your Revit plan. I hope this helps.

Re: Linked CAD file changes position

tmccar — Wed, 19 May 2021 18:14:57 GMT

Yes, I was on a sheet. I linked it from a 3d view and it is positioned correctly, and maintaining its position.
Thanks for your help - this had been bugging me for a long time!

Re: Linked CAD file changes position

barthbradley — Wed, 19 May 2021 18:15:42 GMT

The OP is following my specific instructions in #11. He needs to Link via Shared Coordinates.

Re: Linked CAD file changes position

tmccar — Mon, 28 Jun 2021 11:28:34 GMT

How do I get the map to display upright (for site plan purposes). I have changed view
to True North, but it doesn't change.