unnamed.gh (4.6 KB)
I have a question about 1rail sweep of rhino7 and grasshopper.
Attachment succeeds in rhino with 1rail sweep, but fails in grasshopper.
What should I do? Can someone please tell me?
Rhino always seems to be much more “intuitive” about these situations than GH. The curves were not aligned. The Align Curve Seams component from Pufferfish is used here.
unnamed (3)-b.gh (15.5 KB)
The white group in this GH file does the actual sweep, the other code above that attempts to explain…
The main problem is shown in yellow; your section curves didn’t all start in the correct place. The blue curve is a circle, showing that your rail is not a circle, which contributes to twisting of the PFrames when the ‘Count’ slider is less than five.
sweep_2023Jan27a.gh (15.8 KB)
No plugins.
P.S. Looking again now, I see there is more to it that my solution perhaps doesn’t address correctly? 
P.P.S. Yeah, your section curves are not all the same size/shape. What a hassle! Left and right are the same, top and bottom are two different sizes.
How about this? Copy/move the rail and use Sweep 2, with your sections untouched. (except for their sequence, which I arranged to follow the rails)
sweep_2023Jan27b.gh (7.1 KB)
Thank you!
This is the answer I was looking for.
Thank you for kindly letting me know.
Thank you for your answer.
I tried adding a plug-in, but it didn’t have a component called Align Curve Seams, so I couldn’t use it on my computer.
It’s a pity that you were kind enough to tell me.