Problems with surface triangulation/ meshing

I’m new to Rhino.
I created some surfaces with two-rail simple sweep tool. They are very strangely triangulated (1st screenshot). I exported my model to OBJ and pasted to SketchUp where you can see it’s been triangulated in another odd way. Can I somehow have more control over triangulation? I’d like to see something that simply looks like triangulated quads.

When in Rhino, I cannot smooth these surfaces - this is the other problem but less painful. Tried to play with sweep settings and then ApplyEdgeSoftening, nothing. I’m not in FlatShade mode.

This is the right post with the right question I want to ask. The previous one must be removed. Sorry for mess. In other forums I can edit and remove my own posts… :confused:

You can here too… Press the Edit tool (looks like a pencil) near the lower right hand corner of your post to edit. Press the icon next to it and you should get a “delete this post” (trashcan) option.

Seems like your problem is the input curves for the sweep are polylines, not smooth curves. That’s why the result is segmented. Did you create the rail/profile in Rhino? With what tool?

I created the profiles in SketchUp, then exported to Rhino via 3ds format, as far as I remember. Yes, I think I’m working on polylines, not smooth curves. Should I convert them?

This is the file if you like to take a look.

rhino sweep.3dm (6.4 MB)

Press the … icon next to it and you should get a “delete this post” (trashcan) option.

There’s no “…” button near first post, only near the second one. So I assume only admin can remove a created topic.

Rhino commands usually surfaces which reflect the continuity of the input curves. Polycurves which have kinks usually result in surfaces with kinks. Exceptions include NetworkSrf which essentially internally rebuilds the input curves to smooth curves to create a smooth surface, and commands with “Rebuild input” options. I usually prefer rebuilding or smooth curves directly before creating a surface when I want a smooth surface. Then I have more control over the resulting surface.

I assume that happens after someone has responded to the topic, you can then no longer remove the whole thread including their responses (as that would be removing someone’s post without their authorization). It might even happen if you respond yourself to your first post with a second message…