Site survey/topo/building link have shifted - how to fix?

[patricks]

I just opened a project's building file after not working on it for a couple of weeks, only to find that the site link appears to have shifted.

So I opened the site file, and the topo and the building link (all shared coordinates) appear to still be in the same place. But the site survey CAD link (from which coordinates were acquired for the site, and subsequently for the building) has shifted/rotated off to the side by some random amount.

Now I was able to fix it by deleting the CAD link and re-linking it back in center-to-center so that it came in at the correct rotation. Luckily I had a reference point located in the building Revit link, so I was able to get the CAD file back into the right place so that my topography aligned with the contour lines in the CAD link. After getting it correctly located, I pinned the CAD link so hopefully it won't move again.

Anyone had this happen before? The CAD link that I deleted was also pinned, so how could it have gotten shifted/rotated? I checked the history and no one else had been in the file except me, and the last time I saved it was back around the last week of February.

[aggockel50321]

Once linked, did you go to "Manage Links", select the cad file, and then press the "save location" radio button?

I've had some wander upon re-opening the project, if I don't take this step after getting the cad drawing positioned.

[patricks]

I just opened the site file and went to Manage Links, and I see that the CAD file has the Locations Not Saved column UNchecked. Does that mean that the locations ARE saved? When I select the CAD file in the list and press Save Locations, nothing happens.

Now I have another problem. I checked the properties of the linked CAD file, and it said Shared Location - Not Shared. So I clicked the radio button to move it to the shared location. Did that, saved, everything stayed in the same place and appeared correct.

Then I went back to my building file, updated the Revit Site link, and suddenly the CAD file in the Revit link shifted to the right and down (opposite of where it had shifted before)! The topo in the Revit link did not move, only the CAD file. So I went back and opened the Site file again, and sure enough, the CAD file had shifted to the right and down. The link's properties shows that it's still at the location I had originally set up, but it's clearly not.

Now I am going to try removing the Revit Site link from my building file, and removing the CAD link from the site file completely, and starting over. I linked the CAD file again, but did it by shared coordinates, and it came in at the correct location.

[kreed]

We ran into the same thing on our latest project, exact same situation. The site plan, which was done by civil and landscape based upon another civil's survey would bounce all over the place when we saved to central or opened the file after not working in it for a while.

I sent a support request to Adesk and got a less than satisfactory answer. Essentially, they said DWG files with any elements far out in space cannot use shared coordinates. The problem is it Revit let's you import and makes it appear as if it's letting you place it by Shared Coordinates. There is no warning that says Next time you save this file you will have to spend another hour redoing work that you've done twice already.

Their solution was to clean out the DWG file an remove any elements that are further than 1 mile radius from the origin. Not the easiest thing when your site is nearly 2 miles long to begin with.

The problem was that the survey used map grids as a base point and the DWG origin was 10 miles away. I created a new DWG file that I xrefed the civil DWG into and moved the xref to a 0,0,0 close to our site. It's working now and the file hasn't moved since.

However, one related item to this is that even with the xref solution, the DWG file is quite large in space and we think it is causing graphic display problems. When we zoom in tight to an element and try to draw, move or rotate using snaps the snaps appear on screen as if they are floating away from where the lines and elements are. Again, Adesk blames this on the DWG file being so large in space. I've done everything I can to ensure that the drawings are accurate but the displays just don't match up sometimes.

[patricks]

I know about this issue, but I don't know if that's what's going on here or not.

I checked the CAD site plan file, and the farthest point in the file is indeed right at 1 mile from 0,0,0. However the site plan itself is encompasses nearly a square mile of area, so I don't know what I can do. I guess I could try moving the data so that 0,0,0 sits near the middle of the site plan.

Luckily I have 2 reference planes locating a corner of an existing building in my Revit site file, so it's pretty easy to get the CAD file back to the correct location.