Make Solid From Points By Sections

This command creates a solid model from a collection of x,y,z points by creating cross sections from the points and then stitching the sections together.

Here is an example of an underground cavity with data points all around: top, bottom and sides. One way to model this case is to set the Model Type to Closed, Triangulate Ends to 3D TIN and Section Alignment to Vertical.

Plan view of data points

Resulting 3D Solid colored by normal and showing edges

Here is an example of a tunnel with points at a section interval. For this case, use the CAD Orbit command to rotate the CAD view so that you're looking down the tunnel. Then in this command, set the Section Interval to match the data, Model Type as Closed, Section Alignment as Current 3D View and Triangulate Ends as None.

Plan view of data points

CAD 3D View from Orbit aligned with tunnel

Resulting 3D Solid colored by normal and showing edges

Scan: Reads the input points to find the min and max elevations which are reported at the top of the dialog.
Model Type: Controls whether to create a watertight closed solid such as an underground cavity, or create an open surface solid such as a cliff face. For a Closed model, the points need to cover all sides of the surface (top, bottom, left, right, front, back).
Triangulate Ends: Controls whether to triangulate and cap off the end sections. The By Section method triangulates the section end polylines. The 3D TIN method triangulates all the end points. The None method leaves the ends open such as for a tunnel.
Section Alignment: Sets how to section the points. It is important to align the sections with the data to get good sections. For example, with a tunnel the alignment should go along the length of the tunnel so that the sections are like slicing a carrot into discs. The Vertical method slices by elevation range. The Pick Points method prompts for two points and uses the 3D line between these points for the alignment. The Current 3D View method uses the CAD view. This way you can use the CAD 3D view commands to line up a good view for the points.
Min Edge Length: Sets the minimum length of a triangle edge in the solid. When there are several points closer than this distance to each other, some of these points will be left out of the solid model.
Section Interval: Sets the distance between sections along the alignment. This distance needs to be big enough to ensure that plenty of points are used for each section, and the distance needs to be small enough to create enough sections to model the solid.
Sample Width/Use Full Section: Controls whether to use all the data points between sections or limit the data points to the specified distance from the section line.
Shrink-Wrap Perimeter Reduction: The program triangulates the points for each section and uses the boundary of this triangulation for the section. This option controls how much to tighten this boundary polyline by removing long edges.
Use Interior Points: This option shrink-wraps the interior points and then finds the median with the outer shrink-wrap to create the section polyline.
Use Section Mid-Elevation: Controls whether the section lines use the individual elevations of the data points or the same average elevation for the section.
Use Section Manager: This option shows the generated sections in an editor for making changes before building the model. See the Edit Solid topic for more information on this feature.
Draw Section Polylines: This option draws 3D polylines for the sections on the specified layer.
Display Solid in 3D Viewer: This option will automatically run the 3D Viewer for the resulting solid at the end of the command.

Prompts

Select points to process.
Select objects: pick points
Points to Solid options dialog
Solid File To Write Select MDL file

Pulldown Menu Location: Solid
Keyboard Command: pt2mdl
Prerequisite: points