Thanks for the replies. I've tried both drape and patch on Rhino with limited success -- drape works great on other surfaces or solids, but not with lines (as I recall), and patch only gives a highly "smoothed out" approximation, seemingly regardless of how much I tweak the parameters. However I am still working along those lines. BTW, Rhino is a really powerful little 3d modeling program, using nurbs. I have found that 3d geometries that use boolean operations need to be saved as IGES files to import cleanly into Mastercam -- something that took many hours of head scratching to finally discover. A full version with 30 saves is available for evaluation at www.rhino3d.com. Thanks again!

Hello all. I'm shop supervisor at the Univ. of Arizona College of Architecture, and we've recently acquired a small cnc router, which came with Mastercam. I'm a complete novice, but I've learned a whole lot in the last three months that I've been working with it. A primary reason we purchased the machine is to cut smooth contour site models (topographies) accurately, based on GIS topo maps in DWG format. My dilemma is this -- since the digital GIS maps are a series of topographic lines, I need a way of converting those lines into a surface so as to generate surface toolpaths. Is there a way of doing this in Mastercam, or in any other program for that matter? I feel there must be a way, but I have yet to figure it out. We have Autocad, Rhino, Viz 4, Truespace, and Maya. Any suggestions would be greatly appreciated.