I have a project where I need to make ~2'x2' 3D raised relief topographical maps using a CNC router. I have access to AutoCAD 2012 Architecture, REVIT, Mechanical, and Civil 3D products, and I'm trying to determine how to approach the problem. While I'm not an AutoCAD expert, I have used Mechanical off and on for years, but not the Civil 3D or Map products.
I'm starting with USGS National Map 1/3arc sec elevation data and have it in both ArcGIS, DEM, and GRIDFloat format. The representative areas I'll be dealing with are 1-5mi square, with elevations of less than 200ft. I am having trouble importing the entire 450MB chunk, and don't know how to import a small subset of the data. I have used another product which allows me to extract a subset of the data, generate excellent contours, etc., but good as it is, I'd like to avoid having to purchase this product if at all possible.
I assume that I'll need to import the ArcGIS or DEM data, to create a 3D surface (mesh?) which I can then create tool paths using Mastercam. Using Civil 3D I was able to import a small DEM data set as a test, and create a surface, and the contours appear very good, with the correct elevation attributes, but it appears to be in a 2D space, not 3D, and I am not sure how to apply a mesh to it.
Any and all help would be much appreciated.