Sweep2 Simple Sweep Failed!

Hi Guys!
I tried to use Simple Sweep in Sweep 2 Rail Command. but it doesn’t work. I Considered all possible situation… Rails Rebuilt same and Cross Section is in EditPoint. Any help appreciated! Simple Sweep.3dm (3.3 MB)

Simple sweep in V5 is not available as an option if the conditions cannot be met with the input curves.

“This option generates simpler surfaces in cases when the curves are perfectly set up.”

Note that in V6, the “simple sweep” option has been removed, Rhino does it automatically if it can.

I did two things:
1- rebuilt Rails in the same number of control Points
2- located the cross Section between two Edit Point…
anything I need to do?

As Mitch writes, the “Simple Sweep” option is very tricky to get right. The profile curve needs to be simple and have its ends on the rails. In the attached, I’ve created two new profile curves to more or less have the same shape as your original profile. The “Simple Sweep” option is available for these but you’ll have to run the command two times and join the resulting surfaces.
Simple Sweep-wd.3dm (3.7 MB)
-wim

My guess is the cross sections need to be located between two knots, not “Edit Points” (aka Greville points). Knot locations may or may not coincide with Edit Points depending on knot distribution and parameterization. Knot locations on curves are not directly available. One way to obtain the knot locations is to make a copies of the curves, then ConvertToBeziers on the copies. The knots will be located at the end of the Bezier segments.

For Simple to work, the rails must match exactly in structure, and the sections must touch the rails on corresponding Edit points.

-Pascal