I have a series of building floorplan CAD files which have been georeferenced in ArcGIS and then assigned a spatial coordinate system. Is there a way to re-project these CAD files into another coordinate system?
Yes, I know you can reproject shapefiles and geodatabase feature classes, but these are native CAD files, .dwg. So, to clarify:
I have a .dwg CAD file (actally many files)that I georeferenced and assigned the NAD83 Michigan State Plane South coordinate system. I would like to use it in NAD83 (CORS96) maps without having to do a transformation on the fly all the time, but I need it to remain as a .dwg (not shapefiles or geodatabase feature classes). Is there a way to do this?
You cannot project CAD files while they are in their native format ie .dwg. You can define their projection and then when you add them to ArcMap they will project on the fly. You can do to create a projection for the CAD file by using the georeferencing tools. You do have to have a second data source to georeference the CAD File though. So if you have survey benchmark points in GIS (projected in NAD83 Michigan State Plane South coordinate system) and the CAD file contains them as well you can use the georeferencing tools to create a projection file that will be stored with the CAD drawing so each time it is added to ArcMap it recognizes how to project it. http://resources.arcgis.com/en/help/main/10.2/index.html#//001000000082000000
Thanks for the answer. That is what I had begun to suspect. I was hoping to avoid having to project on the fly, because then when I am editing something else in the map I receive a long list of warnings for the CAD layers not having the same coordinate system. These useless warnings could obscure a warning for one of the shapefiles/feature classes that I really should be aware of.
To bad there is not a way to take the projection that is done on the fly for CAD layers and make it permanent.
I think this is what you want to do. Copy a prj file from a shapefile that uses the same projection as your CAD file. Paste the prj file into the same folder that your CAD file is in. Rename the prj file to have the same name as your CAD file. The CAD file now has its own projection assigned.