Using ExtrudeCrv results in lines on surface, any method of removing?

Hi all,

I am having a bit of an issue with the output of ExtrudeCrv. I need to use a curved line that is the result of polylines and arcs, that has been joined into one open curve. I am using the curve to produce the top surface of a basic ground model for a larger project, but when I execute ExtrudeCrv, the resulting surface has weird lines on it (pictures attached). Initially, I wondered if it was simply producing lines because of the input curve’s control points, but I am unsure if this is the case.

I need to run Make2D afterwards, and the lines significantly slow the process down when producing the final drawing. I wanted to know if anyone could explain how to remove these lines? Or, also, what the cause is? Problem file is attached below.


Extrude Curve produces Lines.3dm (107.0 KB)

The result of joining polylines and arcs will generally be a polycurve, not a single curve. The lines you see are edges and possibly also isocurve.

If you upload a file with the input curve and result of ExtrudeCrv someone may be able to provide a more detailed response.


Thanks for the reply! I will do that now.


Hi -

As David wrote, your curve is a polycurve, made up of 40 curves. The lines you see in your picture are the edges of the individual surfaces of those 40 curves. You can rebuild the curve to turn it into a single curve, which will result in a single surface. Note that if you turn it into a single surface, the Make2D command will only generate the outline - in the top view, that will be a simple rectangle. In the perspective view, that will be “some curve” without any internal definition - but that might be what you need…