Make a beam from a line

Im trying to make a beam from a line existing on Rhino with grasshopper.
I used this

Unfortunately the beam are turning sometimes and i have no idea why.
I also tried with this but it happened the same … Could you help me ?

This is beacause of the axis orientation of each perp frame, use _align plane_on your perp frames with a Z vector as your direction and then use those planes to create your rectangles, this is all purely demonstrative because for real projects with more complex surfaces then a lot more comes into play for the correct orientation f your beams. try to turn on preview of components as you look along your definition to see whats going on at each step, and when you ask something here is always better to upload a file.

Thanks so much it worked :slight_smile: