I have tried again. I think with the method that I used, it should automatically generate a plane that is perpendicular to the Nurbs-Curve at that point. If you play around with the Parameter, at which the plane is generated (i.e. if you change it from 0 to 0.01 or 0.5, you can see that the plane looks more like its perpendicular to the curve).
Yes, the rotation is to turn the polygone in plane. But because that polygone doesn’t work yet, turning the circle in plane is quite unnecessary but shouldn’t cause any trouble. I will try to remove that node and try again without that rotation.
Here is an image of how I created the NurbsCurve. I basically created points along the sides of a rectangular volume (you can see the points in the background). And the goal is to be able to change the weights of these points and thereby change the shape of the curve.
I can’t use the graph since it;s getting some information from the project you’re working on.
But what I can see is that you have some very high value for the degree of the curve. The curve itself seem to have some jagged edges which Dynamo doesn’t like for sweeps.
If that doesn’t work, try reducing the number of sample points used to create the path. Take every third and see if that works, somewhere along the sweep you are folding the shape over itself. That will hopefully illustrate where. Taking the plane at multiple parameters can also help identify this.
If all of that fails, pack the points into a Data.Remember node, or write the X,Y, and Z values into an external file (ie: excel) and we can go from there.
Can you quickly disable all the other geometry display (select all nodes, right click the background, disable preview) other than the circle and polygon, and grab a quick screenshot of those two data previews and the associated geometry.