Exporting from Civil 3D

Sometimes we need to export our drawing files from Civil 3D to plain vanilla AutoCAD. This may be necessary for a variety of reasons: the client or another consultant doesn’t have Civil 3D and they aren’t able to install the Civil 3D Object Enabler, or you are producing an archive set and don’t want to risk future versions of AutoCAD being unable to read old Civil 3D data. Also, given that Civil 3D surfaces take longer to load, you might want to produce vanilla AutoCAD versions of your design surfaces and pipe networks for use as base files on your plan set.

I’ve discovered a few issues with exporting from Civil 3D 2008 to vanilla AutoCAD, and have some workarounds.

Problem #1: Contours don’t retain elevation

If you want to export your contours, they will appear as polylines (light-weight polylines, to be precise) in the exported file, all with an elevation of zero. You might need that! There are two fixes for this:

1. Use the “Surfaces > Utilities > Extract Objects from Surface” command. This will create polylines with elevation data in your current drawing, and which will remain in your drawing when you export. You’ll want to hide the contours in the original surface, though, otherwise you’ll export both the extracted polylines and the 0-elevation polylines.
2. Another option is to rotate your view so you are looking at your surface in 3D (shift-middle mouse button). You may have to edit your surface style so that the contours are displayed. Now when you export the contours will export as polylines with elevation data. Open your file up, type “Plan” to return to 2d View, and you’re set.

A few caveats: with method 2, profiles will not properly export. With method 1, you have to Extract Objects from every surface (you can’t just “select all”), so if you have a lot of surfaces, method 2 might be easier.

Problem #2: Object Coloring/Text Hatches

When Civil 3D exports labeled contours or certain pipe labels, it creates a hatch behind the text, and colors that hatch whatever your background color is. If your model space is anything but white, the hatch will show up in your plots, often as a filled black rectangle. So you need an quick way to fix that. Again, there are two possible solutions:

1. Change the hatch to white (255,255,255). You can select everything in your drawing and then select “hatch” from the Properties window drop-down box, then adjust the color from there. If you have other hatches in your drawing, you may want to isolate the layer(s) that the text hatches are on using LAYISO.
2. You can delete all of the hatches (using the FILTER command) and replace them with background masks. Again, you might want to isolate the relevant layers before doing this. Use the Properties window drop-down to select all MText entities. Once you have selected only MText that you want to mask (using Shift-selections to remove those that you don’t), you can click on the ellipses next to Background Mask and set your mask.
   Be sure to set the background color to “use drawing background color”.

   

Another related problem is that a lot of entities will be exported with their entity color set to whatever their layer color was. Or, if the entity was set to a specific color in the style settings, to that color. Generally, I like to set everything to BYLAYER. So, I recommend selecting everything and setting to it to BYLAYER.

Problem #3: Linetypes will not export properly

I’ve only encountered this once, and it took a minute to figure out what was going on. After exporting a pipe network to vanilla AutoCAD, the line on the bottom is the same linetype as the one on the left, but rotated around its axis.

The solution here is to FLATTEN the offending lines. That’s it.

I hope this helps. Happy exporting!