How do I give my surface to an AutoCAD user?

You know, Civil 3D objects are great. I absolutely love them – the ways that I can work with them, display them, and tweak them are simply incredible. However, for someone wanting to view Civil 3D objects who DOESN’T have Civil 3D, that ends up being a nightmare.

Take a topo for example. You often have to ship it out, maybe to an architectural group running ADT. If you export to AutoCAD, you get nice contours. However, upon further inspection, you find that they’re polylines, and they’re all at a 0 elevation!!! That’s not good – what on earth would someone do with contours that are at an elevation of 0? “Not much” is the correct answer, by the way.

To get your surface into plain AutoCAD, you’re going to have to do something bad…something that we never like to do. You’re going to need to EXPLODE your surface. What’s more, you’re going to have to explode your surface TWICE! Yes, one litle stick of dynamite won’t do it, you’re going to have to do it twice. Exploding once retains the object, doing it twice explodes it to 2D polylines (with the correct elevation) and labels intact. Now, and only now are you ready to export your drawing to AutoCAD.

Oh, and here’s a tip: Don’t explode your good surface. That would make it useless to YOU, and that’s certainly a bad idea. Copy your surface! How to do this? It’s as easy as using the AutoCAD “COPY” command – just select a base point of 0,0,0 and a copy point of 0,0,0 (or a displacement of 0) and you’ve got a copy of your surface over in Prospector that you can explode to your heart’s content.

Have fun!


  1. Robin Capper says:

    Doents work with AutoCAD but as an ADT user I’d prefer LandXML 🙂

  2. John Burrill says:

    Is there some reason that the object enabler for Civil 3D wouldn’t be adequate for AutoCAD users?

  3. Jason says:

    John –

    The object enabler will allow you to see the proxy graphics, but not perform any calcs on them. The original post was inspired by a company wanting to give a surface to a contractor to perform volume calcs.