I have an issue with linked CAD files in a current project where linking the geolocated survey dwg file moves the survey station layers approx 1000km North East of the drawing elements. It's only the survey stations that move so I am assuming this is to do with the geolocation of the dwg file but cannot find any resolution to the issue.
I have tried linking by shared coordinates, internal origin, centre to centre, and manual, as well as all the other link options. Has anyone had this same issue or found a solution to it?
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Hard to follow. Are you saying that you have multiple Geolocated DWGs that align perfectly in AutoCAD, but when Linking into Revit, one of the DWGs causes the other Linked DWGs to move (e.g. change physical location in the Project)?
No, it's a single file that reads fine in CAD (I wrote files in the first sentence, whereas it should just be file). When I link this one dwg file into Revit, one specific layer moves away from the rest of the layers by approx 1000km. It reads as a change in the dwg file, but opening it in CAD shows no change in position. The screenshot below illustrates the positions, the DWG is bounded by the blue box and the red highlights the position of the layers in question.
Are you using Link Topography method?
Link Topography | Revit Products 2019 | Autodesk Knowledge Network
My topography is a linked Revit toposurface and context model. The DWG in question is a 2D survey drawing I am using as reference, it doesn't contain any topography. Could the link above be used in this instance?
Just to confirm my understanding; the DWG is geolocated; right?
About Using Grid Coordinates from a Linked DWG | Revit Products 2021 | Autodesk Knowledge Network
Specify Coordinates Before Linking Site Data | Revit Products 2019 | Autodesk Knowledge Network
Correct. The survey stations identified by coordinates in the CAD file report the correct N/S & E/W when queried in both the native file and in the .rvt but all the drawn elements appear at a distant location when the file is linked in.
Even if it weren't in the correct location, the issue of layers being in different positions when linked in than in the actual file would still be causing me issue as the extent of the link is enormous.
I've watched it, it doesn't help here unfortunately. It doesn't explain why all but two layers in the linked dwg file change position when linked into my model.
How far away from the Internal Origin is the DWG? If it's too far away, that could easily cause what you are describing.
Reorient the Geolocation Marker as described here in Message 30:
Thanks for the suggestions. I'm really stumped here. The Internal Origin in my .rvt is quite close to the intended position of the dwg - less than 20m away from several survey stations that I've used to check and recheck the geolocation. The other layers of the dwg are over 1000km away. The survey stations in the dwg are correctly located on linking in the file to the .rvt, I really am stumped as to how the relationship between the survey station layer and all the other layers get completely broken in such a way when linked.
I removed the geolocation information from the dwg file and the layers now maintain their correct relationship to each other when linked. This is good enough for me, I can position it manually via the survey stations, but I am still none the wiser on the cause of the issue.
Can you share the DWG file?
@Shane_Fitz wrote:I'm really stumped here.
You are going through the exact same thing the OP is going through in the above thread I linked you to. In that case, the only two solutions where to Remove or Reorient the Geolocation Marker. I'm partial to Reorienting the Marker because it preserves the GIS Coordinates.
@syman2000 Unfortunately not as the project is commercially sensitive (covered by an NDA) and sharing any identifiable info would get me sacked.
@Anonymous I appreciate the time you have put into responding to me, thank you, but I don't think this issue is the same although some elements might be. The issue at the heart of my problem is that the position of different parts of the dwg file change location when linked in. One layer (the survey stations) comes in at the right position - geolocated according to the ITM grid system with no need to acquire the coordinates - while all the other layers (306 2D CAD layers) seem to lose their geolocation information and move to what I would suspect is 0,0 on the ITM grid system - somewhere in the middle of the Atlantic Ocean. The locations of all layers are coincident in the CAD file but not so in the .rvt when linked. Reorientation of the Geolocation marker as you suggested didn't solve it but removal did. On that basis I'll flag this as solved.
Since you can't shared the file, can you check in AutoCAD. First I would type in the command ERASE. Then select all and then type in R (remove) and select the objects you want to keep on view. What this will do is erase any object that isn't in the view.
After you done that, you may want to see how many objects in your DWG are binded XREF as blocks or regular block. You may want to explode them. Some blocks have point attach to them which Revit won't be able to pick up. You can use DDPTYPE and change the point to different marker so you can see what objects are out there.
Also in the past CAD link I've work with, I notice spline and arc can create huge center point distance when link into Revit. Revit will treat those as zoom out distance. It is annoying and no way to fix it until you convert spline & arc as line segment using lisp.
@Shane_FitzDid you ever get this solved properly, instead of just deleting the offending layers? Do you remember if your offending layers were locked?
I've found that if a DWG linked file with coordinates has locked layers, those locked layers move exactly the coordinates-amount further away.
So, let's say that the building is at coordinates 350x400km. That fits just well with all of Revit's geolocation and all that jazz. But all the locked layers move *another* 350x400km away, which puts them at 700x800km coordinates.
If I unlock the layers in AutoCAD and reload in Revit, those layers move down to their correct coordinates, but of I re-lock them, they move away to 2x coordinates again.
Weird Revit (2024?) bug. ![]()
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